appendix 10-c tdr mi-3 - impact assessment agency · tdr mi-3 - orange sea pens tdr . port metro...
TRANSCRIPT
APPENDIX AIR10-C Technical Data Reports Containing Habitat
Maps at Local and Regional Scales
TDR MI-3 - Orange Sea Pens TDR
PORT METRO VANCOUVER | Roberts Bank Terminal 2 Information Request Response This page is intentionally left blank
ROBERTS BANK TERMINAL 2
TECHNICAL DATA REPORT
Marine Invertebrates
Orange Sea Pens (Ptilosarcus gurneyi)
Prepared for: Port Metro Vancouver 100 The Pointe, 999 Canada Place Vancouver, BC V6C 3T4 Prepared by: Hemmera Envirochem Inc. 18
th Floor, 4730 Kingsway
Burnaby, BC V5H 0C6 And Archipelago Marine Research Ltd. 525 Head Street Victoria, BC V9A 5S1 File: 302-042.02 November 2014
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens November 2014
Technical Report / Technical Data Report Disclaimer
The Canadian Environmental Assessment Agency determined the scope of the proposed Roberts Bank
Terminal 2 Project (RBT2 or the Project) and the scope of the assessment in the Final Environmental
Impact Statement Guidelines (EISG) issued January 7, 2014. The scope of the Project includes the
project components and physical activities to be considered in the environmental assessment. The scope
of the assessment includes the factors to be considered and the scope of those factors. The
Environmental Impact Statement (EIS) has been prepared in accordance with the scope of the Project
and the scope of the assessment specified in the EISG. For each component of the natural or human
environment considered in the EIS, the geographic scope of the assessment depends on the extent of
potential effects.
At the time supporting technical studies were initiated in 2011, with the objective of ensuring adequate
information would be available to inform the environmental assessment of the Project, neither the scope
of the Project nor the scope of the assessment had been determined.
Therefore, the scope of supporting studies may include physical activities that are not included in the
scope of the Project as determined by the Agency. Similarly, the scope of supporting studies may also
include spatial areas that are not expected to be affected by the Project.
This out-of-scope information is included in the Technical Report (TR)/Technical Data Report (TDR) for
each study, but may not be considered in the assessment of potential effects of the Project unless
relevant for understanding the context of those effects or to assessing potential cumulative effects.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - i - November 2014
EXECUTIVE SUMMARY
Port Metro Vancouver (PMV) is assessing the potential to develop the Roberts Bank Terminal 2 Project
(RBT2 or the Project), a new three-berth marine terminal at Roberts Bank in Delta, B.C. The Project is
part of PMV’s Container Capacity Improvement Program (CCIP), a long-term strategy to deliver projects
to meet anticipated growth in demand for container capacity to 2030.
Hemmera has been retained by PMV to undertake environmental studies related to the Project. This
technical data report focusses on the orange sea pen (Ptilosarcus gurneyi), a colonial octocoral that is
broadly distributed along the Pacific coast of North America, from Alaska to California. A large
aggregation, or bed, of orange sea pens, has been consistently observed at Roberts Bank, along the
delta-front slope off the seaward face of Westshore Terminals (Golder 1996, Triton 2004, Archipelago
2009). The current state of knowledge on this species is limited, and many aspects of its biology and
ecology remain poorly understood, both in B.C. waters and throughout the rest of its range. To address
data gaps at both local and regional scales, this report is divided into three major sections: i) available
literature and data review; ii) site-specific study describing the ecology and distribution of orange sea
pens at Roberts Bank; and iii) local knowledge study compiling anecdotal ecological and biological
information on orange sea pens across their geographic range.
Building on previous surveys conducted in 2003 and 2008, towed underwater video (SIMS) and SCUBA
dive surveys were conducted in September 2011, with the objective to quantify orange sea pen
distribution and densities at Roberts Bank, as well as document associations with other species, including
fish and macroinvertebrates. Field data were supplemented by a local knowledge survey, conducted in
January 2013, which collected anecdotal information on orange sea pen ecology, distribution, and value
by the way of a questionnaire.
SIMS and SCUBA results at Roberts Bank suggest that: i) the spatial extent of orange sea pens is greater
than what has been previously documented; ii) the orange sea pen bed is not comprised of a single age
class, as was previously understood; iii) there appears to be a lack of natural predators; iv) orange sea
pens provide habitat for a number of species; and v) other fauna (i.e., crustaceans, sea stars, anemones,
and fish) are more likely to occur within areas of continuous to dense sea pens relative to areas where
distribution is few to patchy or absent.
Forty-three responses (51% response rate) were received from the local knowledge survey, providing
valuable information on geographical range, ecological significance, abiotic drivers, and value of orange
sea pens in the northeast Pacific. Taken together, these responses provide a comprehensive snapshot
of our current understanding of this poorly studied species.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - ii - November 2014
TABLE OF CONTENTS
EXECUTIVE SUMMARY ............................................................................................................................... I
1.0 INTRODUCTION .............................................................................................................................. 1
1.1 PROJECT BACKGROUND ........................................................................................................ 1
1.2 ORANGE SEA PEN STUDY OVERVIEW ..................................................................................... 1
2.0 REVIEW OF AVAILABLE LITERATURE AND DATA ................................................................... 3
2.1 TAXONOMY AND DISTRIBUTION ............................................................................................... 3
2.2 LIFE HISTORY AND BEHAVIOUR .............................................................................................. 4
2.3 ECOLOGICAL ROLE ................................................................................................................ 5
2.3.1 Trophic Interactions ............................................................................................... 5
2.3.2 Species Associations ............................................................................................. 5
2.3.3 Habitat Value .......................................................................................................... 6
2.4 HABITAT REQUIREMENTS AND LIMITING FACTORS ................................................................... 7
2.5 CONSERVATION STATUS ........................................................................................................ 8
2.6 SUMMARY OF PREVIOUS STUDIES AT ROBERTS BANK ............................................................. 8
3.0 ECOLOGICAL STUDY .................................................................................................................... 9
3.1 STUDY AREA ......................................................................................................................... 9
3.2 TEMPORAL SCOPE................................................................................................................. 9
3.3 STUDY METHODS .................................................................................................................. 9
3.3.1 SIMS Survey Methods & Data Analysis ................................................................. 9
3.3.2 SCUBA Survey Methods and Data Analysis ....................................................... 15
3.4 RESULTS ............................................................................................................................ 15
3.4.1 SIMS Results ....................................................................................................... 15
3.4.1.1 Delta Front Slope ............................................................................... 15
3.4.1.2 Existing Dredge Basin ....................................................................... 17
3.4.1.3 Roberts Bank Overall ......................................................................... 17
3.4.2 SCUBA Results .................................................................................................... 25
3.4.2.1 Dive Site SP1 ..................................................................................... 25
3.4.2.2 Dive Site SP2 ..................................................................................... 25
3.4.2.3 Dive Site SP3 ..................................................................................... 26
3.5 KEY FINDINGS ..................................................................................................................... 27
3.5.1 Discussion of Key Findings .................................................................................. 27
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - iii - November 2014
3.5.2 Data Gaps and Limitations ................................................................................... 30
4.0 LOCAL KNOWLEDGE STUDY ..................................................................................................... 31
4.1 STUDY METHODS ................................................................................................................ 31
4.2 RESULTS ............................................................................................................................ 32
4.2.1 Geographical Range and Ecological Significance ............................................... 32
4.2.1.1 Species Distribution ........................................................................... 32
4.2.1.2 Observed Densities ........................................................................... 32
4.2.1.3 Ecologically-Linked Species .............................................................. 32
4.2.2 Abiotic Drivers ...................................................................................................... 33
4.2.2.1 Substrate Type .................................................................................. 33
4.2.2.2 Flow ................................................................................................... 33
4.2.2.3 Depth ................................................................................................. 33
4.2.2.4 Unique Habitat Attributes ................................................................... 33
4.2.2.5 Significance of Abiotic Factors .......................................................... 36
4.2.2.6 Additional Abiotic Factors .................................................................. 36
4.2.3 Ascribed Value ..................................................................................................... 36
4.2.3.1 Ecosystem Functions ......................................................................... 36
4.2.3.2 Anthropogenic Value ......................................................................... 36
4.2.3.3 Additional Comments ......................................................................... 37
5.0 CLOSURE ...................................................................................................................................... 38
6.0 REFERENCES ............................................................................................................................... 39
7.0 STATEMENT OF LIMITATIONS ................................................................................................... 44
List of Tables
Table 1-1 Orange Sea Pen Study Components and Major Objectives .............................................. 1
Table 3-1 Faunal Distribution Class Codes for SIMS Bio-classification ............................................ 11
Table 3-2 Summary of the Sea Pen Dive Survey Conducted on Roberts Bank October 19, 2011 .. 15
Table 3-3 Summary of Predictive Diagnostic Coefficients in the Best-fit Generalised Linear Models
for Four Faunal Groups at Roberts Bank .......................................................................... 17
Table 3-4 Sea Pen Density Data for Dive Sites SP2 (sparse) and SP3 (dense) at Roberts Bank on
October 19, 2011 .............................................................................................................. 26
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - iv - November 2014
List of Figures
Figure 3-1 Orange Sea Pen Study Area at Roberts Bank ................................................................. 12
Figure 3-2 Towed Underwater Video (SIMS) Tracklines over Time (2003, 2008, 2011) at Roberts
Bank .................................................................................................................................. 13
Figure 3-3 2011 Towed Underwater Video (SIMS) Tracklines and SCUBA Dive Sites at Roberts
Bank .................................................................................................................................. 14
Figure 3-4 Orange Sea Pen Distribution at Roberts Bank ................................................................. 19
Figure 3-5 Slope Profiles along Orange Sea Pen Density Gradients ................................................ 20
Figure 3-6 Cumulative Distribution of Crustaceans from SIMS Surveys (2003, 2008, 2011) at
Roberts Bank .................................................................................................................... 21
Figure 3-7 Cumulative Distribution of Sea Stars from SIMS Surveys (2003, 2008, 2011) at Roberts
Bank .................................................................................................................................. 22
Figure 3-8 Cumulative Distribution of Anemones, Sea Cucumbers, and Snails from SIMS Surveys
(2003, 2008, 2011) at Roberts Bank ................................................................................. 23
Figure 3-9 Cumulative Distribution of Marine Fishes from SIMS Surveys (2003, 2008, 2011) at
Roberts Bank .................................................................................................................... 24
Figure 4-1 Anecdotal Sea Pen Observations along the Pacific Coast ............................................... 34
Figure 4-2 Anecdotal Sea Pen Observations in the Strait of Georgia ................................................ 35
List of Appendices
Appendix A Photographs
Appendix B Statistical Summaries
Appendix C Local Knowledge Survey Questionnaire and Results
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 1 - November 2014
1.0 INTRODUCTION
This section provides an overview of the study, including project background and the study components
and major objectives.
1.1 PROJECT BACKGROUND
The Roberts Bank Terminal 2 Project (RBT2 or Project) is a proposed new three-berth marine terminal at
Roberts Bank in Delta, B.C. that could provide 2.4 million TEUs (twenty-foot equivalent unit containers) of
additional container capacity annually. The Project is part of Port Metro Vancouver’s Container Capacity
Improvement Program, a long-term strategy to deliver projects to meet anticipated growth in demand for
container capacity to 2030.
This technical data report (TDR) describes the results of orange sea pen (Ptilosarcus gurneyi) studies
and is split into two sections: i) ecological survey; and ii) local knowledge survey. Methods, results, and
discussion are described below for each study.
1.2 ORANGE SEA PEN STUDY OVERVIEW
A review of available information and state of knowledge was completed for orange sea pens to identify
key data gaps and areas of uncertainty within the general Project area. This TDR describes the study
findings for key components identified from this gap analysis. Study components with their major
objectives and a brief overview are provided in Table 1-1.
Table 1-1 Orange Sea Pen Study Components and Major Objectives
Component Major Objectives Brief Overview
SIMS (Subtidal Imaging and Mapping System) survey
Map and classify the geographic extent of sea pen distribution at Roberts Bank.
A towed underwater video (SIMS) survey was conducted in 2011 to map their spatial extent at Roberts Bank. Builds on SIMS surveys conducted in the same general area of Roberts Bank in 2003 and 2008.
SCUBA survey Collect sea pen density and associated species information.
SCUBA surveys were conducted in 2008 and 2011 at three sites along a sea pen density gradient to quantify densities and to characterise the associated biophysical environment.
Local Knowledge Survey
Gain a better understanding of the spatial extent, life history, and ecological importance of sea pens along the northeast Pacific coast.
Individuals possessing relevant expertise, experience, and/or knowledge pertaining to orange sea pens were contacted for their input via a local knowledge questionnaire.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 2 - November 2014
The current state of knowledge on orange sea pens, and on cold-water corals in general, is limited. Little
is known about their abundance, distribution, or ecological role in B.C. and throughout the rest of their
geographic range. Many aspects of orange sea pen biology and ecology are not well studied or
understood, and often based on speculation about possible similar traits with species in other regions,
such as the Arctic, North Atlantic, and tropical environments.
The ecological study component builds on previous work conducted by Archipelago (Triton 2004,
Archipelago 2009) using SIMS and SCUBA surveys to characterise orange sea pen spatial extent and
densities, and attempts to better understand ecosystem interactions of orange sea pens, and the extent
to which dense aggregations may provide habitat complexity and structural relief for macroinvertebrates
and fish. The local knowledge survey addresses several data gaps around orange sea pen biology and
ecology through the collection of anecdotal information.
Data on abiotic drivers of orange sea pen density and distribution are presented and discussed in the
Habitat Suitability Modelling TDR (Hemmera 2014a), which was used to map areas of optimal sea pen
habitat at Roberts Bank. Additionally, the Benthic Subtidal TDR (Hemmera 2014b) provides additional
data on orange sea pen densities, habitat use, and ecosystem interactions at depth ranges (up to -40 m
CD), which were beyond the limit of SIMS.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 3 - November 2014
2.0 REVIEW OF AVAILABLE LITERATURE AND DATA
A thorough review was undertaken for information on orange sea pens, specifically their ecology and
habitat preferences at Roberts Bank and across their entire geographic range. Numerous literature and
data sources were consulted, including:
Publicly available Aboriginal Traditional Knowledge (ATK);
Workshops with Tsawwassen First Nation (TFN);
Books;
Academic journals;
Databases (e.g., DFO WAVES Catalogue; NOAA);
Consultant reports;
Government technical reports; and
Expert opinion.
No ATK references to orange sea pens were identified and TFN community members indicated that the
species holds no cultural or socioeconomic value to their community. Less than ten studies on orange
sea pen were found, reflecting the paucity of literature and how cursory our understanding of this species
remains. Given the limited information, this report will be informed by work on related species and in
other areas (e.g., Arctic, Atlantic, tropics).
2.1 TAXONOMY AND DISTRIBUTION
Sea pens are octocorals in the order Pennatulacea and, along with the true soft corals and gorgonians,
form the subclass Octocorallia within class Anthozoa and phylum Cnidaria. There are 16 families of sea
pens with approximately 300 species occupying both tropical and temperate waters worldwide. According
to the World Register of Marine Species (WoRMS 2008), the genus Ptilosarcus is comprised of two
species, including the orange sea pen. In the Pacific Northwest, orange sea pens appear to be the most
common sea pen in shallow water, while several other species of sea pens (Virgularia sp., Stylatula sp.
and Acanthoptilum gracile) have also been documented (Lamb and Hanby 2005).
Individual sea pens are actually colonies of many polyps (like a coral head) rather than a single animal
(like an anemone), and the polyps show an eight-fold symmetry (Fuller et al. 2008). Orange sea pens,
and pennatulaceans in general, are known to form dense aggregations, known as sea pen beds, but are
otherwise broadly distributed at low density (Fuller et al. 2008). Individual colonies can consist of tens of
thousands of polyps, and a large sea pen bed can easily comprise over 40,000 individuals (Erhardt and
Moosleitner 1998).
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 4 - November 2014
Orange sea pens are found throughout the northeastern Pacific from Alaska to Southern California
(Shimek 2011), and at a depth range that includes the lowest intertidal zone to depths of about 150
metres, but they are most abundant in shallow waters (Shimek 2011). In the 1960s, Birkeland (1969)
documented an extensive zone of dense orange sea pens (up to 22/m2) in depths of -10 to -25 m from
Olympia to Everett Washington, a distance of over 150 km of coastline. Density was lower at both
shallower (0 to -10 m) and deeper (-25 to -50m) depths. A more recent study by Kyte (2001) showed that
the large populations described by Birkeland (1969) are no longer present and remaining populations are
relatively sparse and patchy.
2.2 LIFE HISTORY AND BEHAVIOUR
Sea pens are sessile (i.e., immobile) macroinvertebrates, living in unconsolidated ocean bottom
sediments. They are not fastened to the substrate and are capable of locomotion by crawling out of the
sediment, inflating with water, and drifting in the currents. Fully-expanded, large adult individuals may
extend 60 cm above the seafloor, with their base (termed “peduncle”) burrowed 15 to 30 cm into the
sediment (Shimek 2011). Orange sea pens may live up to 15 years and take five or six years to reach
sexual maturity (Birkeland 1974).
In orange sea pens, the sexes are separate (i.e., each colony of polyps is either male or female), and
reproduction is sexual, through broadcast spawning of gametes (Edwards and Moore 2008). Eggs and
sperm are released through the mouths of the polyps and fertilization takes place externally (Chia and
Crawford 1973). The total fecundity of female sea pens is high, ranging from approximately 30,000 to
200,000 eggs per colony (Chia and Crawford 1973, Soong 2005). In B.C. waters, orange sea pens spawn
in late March, generally in the first week following the spring equinox (Chia and Crawford 1973, Shimek
2011). The free-swimming larvae do not feed and will settle within seven days if a suitable substratum,
such as coarse sand, is encountered (Chia and Crawford 1973).
Studies in Puget Sound by Birkeland (1968, 1974) indicate that larval settlement can be patchy in space
and highly episodic in time giving rise to discontinuous populations differing in age and size. Large year-
to-year differences in recruitment rates were also seen in Renilla kollikeri, a sea pen from the coast of
California (Davis and VanBlaricom 1978). Chia and Crawford (1973) posit that the nature of the
substratum at the time of larval settlement dictates recruitment success in any given area, and hence the
patchiness of distribution. They further suggest that stochastic recruitment patterns of orange sea pens, in
both time and space, are actually a major defense mechanism, making the species generally unavailable
to predators.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 5 - November 2014
Orange sea pens can contract their bodies and burrow into the sediment by expelling water and mucus
from their hydroskeleton (Kozloff 1993). They alternately expand for feeding and contract into the
sediment at irregular intervals, a behavioural pattern apparently unrelated to environmental factors such
as current velocity, turbidity, and light level (Birkeland 1974, Dickinson 1978) or available food supply
(Shimek 2011). Although the ecological significance of this behavioural rhythm is uncertain, burrowing
may allow orange sea pens to be less conspicuous to predators (Birkeland 1974). While diving in Puget
Sound, Birkeland (1968) observed that only about 26% of the sea pens were exposed at any one time.
2.3 ECOLOGICAL ROLE
2.3.1 Trophic Interactions
Orange sea pens are passive suspension feeders whose diet consists mainly of phytoplankton (Best
1988). In turn, they are fed upon by several species of predatory sea stars and nudibranchs. Of the
nudibranch predators, striped (Armina californica) and diamond back (Tritonia festiva) nudibranchs feed
exclusively on sea pens, while the opalescent nudibranch (Hermissenda crassicornis) has a relatively
diverse diet, and feeds on a variety of other invertebrates as well (Birkeland 1974). Adult sea pens are
mostly eaten by sea stars (Birkeland 1974). The spiny red sea star (Hippasteria spinosa) is a specialised
orange sea pen predator, while rose (Crossaster papposus) and vermillion (Mediaster aequalis) stars
consume sea pens opportunistically. Leather stars (Dermasterias imbricata) consume a variety of prey
sources, but when found in sea pen beds, feed almost exclusively on them. Birkeland’s studies (1969,
1974) describe the orange sea pen’s ecological importance as being keystone, particularly for the
predators that feed exclusively on them; however, there are no reports of fish or macroinvertebrates (e.g.,
Dungeness crabs, Metacarcinus magister) feeding directly on orange sea pens, and accounts of
predation on other sea pen species are limited.
2.3.2 Species Associations
Habitat complexity and heterogeneity have been linked to changes in organism abundance and diversity
in a variety of terrestrial and aquatic settings (Bell 1985, Levin and Dayton 2009). Sea pen beds provide
important structure in low-relief sand and mud habitats where there is little physical habitat complexity,
thus providing shelter from currents and predators (Tissot et al. 2006). Sea pens are also considered
“ecosystem engineers”, which shape the environment by burying into soft sediments, enabling deep
oxygen penetration as well as modifying hydrodynamics, and allowing nutrients and plankton to be
retained near the sediment thereby supplying the detrital food chain (Tissot et al. 2006, Boutillier et al.
2010). Sea pens are thought to contribute substantially to the species richness of their respective
environments, particularly in terms of small planktonic and benthic invertebrates that, in turn, may be
preyed upon by fishes (Hughes 1998, Beaulieu 2001, Buhl-Mortensen and Mortensen 2004, Tissot
et al. 2006).
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 6 - November 2014
Sea pens may provide habitat complexity, and structural relief for fish and macroinvertebrates that favour
emergent structures (e.g., juvenile flatfish) (Ryer et al. 2004, 2007, Pirtle 2005, Stoner et al. 2007). In
Alaska, cods and pollocks (family Gadidae) were frequently caught with sea whips and sea pens,
including orange sea pens, as bycatch (Malecha et al. 2005). Fisherman from Port-Aux-Basques,
Newfoundland identified areas with sea pens as being good fishing grounds, claiming areas with sea
pens have more and larger Atlantic cod and halibut than areas without (Colpron et al. 2010). Stripetail
rockfish (Sebastes saxicola) were observed using sea pens (primarily Stylatula spp.) as a nursery ground
in California (Field et al. 2001), and locally in Puget Sound, the density of geoducks (Panopea generosa)
was significantly correlated with orange sea pens (Goodwin and Pease 1991). Several of these
documented associations were hypothesised to be coincidental (e.g., rockfish, geoduck), whereby fish or
macroinvertebrates share similar habitat requirements with sea pens (e.g., in areas of high flows for
enhanced prey delivery), but have no direct association or functional relationship (Auster 2005).
Other studies have not found relationships between fish distribution and sea pens (Tissot et al. 2006,
Edinger et al. 2007, Hixon and Tissot 2007). While results indicated the fish and invertebrates considered
in these studies did not have a strong or obligate relationship, the authors suggest that the importance of
soft corals, sea pens, and small gorgonians as potential fish and invertebrate habitat, particularly for
juveniles, should not be overlooked.
2.3.3 Habitat Value
Considering the knowledge gaps that exist for orange sea pens, they likely provide a number of
ecosystem functions that are not yet fully understood (Diaz et al. 2003). The value of sea pen
aggregations in general is increasingly being recognised by international organizations and governments
in parts of Canada, the United States, and Europe.
In the Gulf of St. Lawrence, Fisheries and Oceans Canada (DFO) considers high concentrations of sea
pens and sponges as habitats suitable for the establishment of highly diverse benthic communities, and
recognises sea pens as important habitat for both fish and invertebrates (DFO 2012). Concern over
destructive fishing methods, such as bottom trawling, has led corals (including sea pens) to be defined as
“sensitive” and “unique” habitats within the Laurentian Channel Area of Interest (AOI) (DFO 2012). In the
Canadian Arctic, Northern Baffin Bay was designated as a new Ecologically and Biologically Significant
Area (EBSA) based on the presence of significant concentrations of sea pens (Ombellula sp.)
(Kenchington et al. 2011). More locally, the report, Ecosystem Overview Report of Pacific North Coast
Management Area (PNCIMA) by DFO (2007), highlighted that cold-water corals (including unspecified
species of sea pens) and sponges may provide essential habitat for some benthic organisms, including
many juvenile and some adult fish species (especially rockfish).
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 7 - November 2014
In Alaska, sea pens, sea whips, corals, sponges, and other “living substrates” have been identified as
Habitat Areas of Particular Concern (HAPC) (Heifetz 2002). A HAPC is defined as a habitat that is
ecologically important, sensitive to disturbance, stressed, or rare. HAPCs are not given any regulatory
protection; however, projects with potential adverse impacts to HAPCs tend to be more heavily
scrutinised during the assessment process (NOAA 2011). Further, in New England, sea pens, stony
corals, and soft corals/gorgonians were identified as structural components of fish habitat in a
vulnerability assessment, conducted as part of a model to evaluate the impacts of fishing on essential fish
habitat (NOAA 2010).
The United Nations Food and Agriculture Organization (FAO) recognises certain cold-water corals,
including representatives from class Octocorallia, to which sea pens belong, as meriting vulnerable
marine ecosystem (VME) status given their vulnerability to most kinds of bottom fishing (FAO 2008). The
Northwest Atlantic Fisheries Organization (NAFO) also identified sea pen beds as a component of
Vulnerable Marine Ecosystems, while simultaneously acknowledging that not all corals and sponges meet
criteria associated with vulnerability (Fuller et al. 2008). Sea pens are also included on an initial OSPAR1
list of Threatened and/or Declining Species and Habitats, recognising the role sea pens play in creating
complex habitats with higher macrofaunal species diversity (OSPAR 2010).
2.4 HABITAT REQUIREMENTS AND LIMITING FACTORS
According to a review of sub-tidal benthic habitats and invertebrate biota in the Strait of Georgia, orange
sea pens are characteristic of shallow (0 to 30 m) silt/sand habitats (Burd et al. 2008). The size
distribution of particles in marine sediment is an important ecological parameter that can have a major
influence on the composition of the biological community (Hughes 1998). While sea pens are anchored
within the sediment, they do not depend upon it for food; however, particle size and associated organic
content are thought to be the two major factors inducing orange sea pen larval settlement (Chia and
Crawford 1973). If appropriate sediments are not available, settlement and metamorphosis may be
delayed for as much as a month, and without appropriate sediment, the sea pen will die (Shimek 2011).
As passive suspension feeders, orange sea pens are highly dependent on ambient flow conditions for
feeding (Best 1988), but are also capable of shaping the environment by modifying local hydrodynamics
to optimise their food uptake (Buhl-Mortensen et al. 2010). Burd et al. (2008) reported finding sea pens
and sea whips in higher current areas. Through a series of laboratory experiments, Best (1988)
demonstrated that sea pen volume flow rates (i.e., water that passes through a sea pen) initially increase
with increasing flow speed, but subsequently peak and decline because the organism becomes so bent
back by the flow that more water tends to flow over, rather than through, the filter. These findings suggest
that there is an optimal flow range wherein sea pens are able to maximise access to food without being
physically deformed, or uprooted, by the flow.
1 The OSPAR Convention is the current legal instrument guiding international cooperation on the protection of the marine
environment of the Northeast Atlantic. Work under the Convention is managed by the OSPAR Commission, made up of representatives of the Governments of 15 Contracting Parties and the European Commission, representing the European Union.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 8 - November 2014
2.5 CONSERVATION STATUS
Orange sea pens are not protected under any provincial or federal legislation.
In 2011, DFO released a Pacific Region Cold-Water Coral and Sponge Conservation Strategy that
recognises the sensitivity of these biogenic habitats to human activities, and aims to promote their
conservation, health and integrity (DFO 2011). Orange sea pens are one of 80 species of cold-water
corals and sponges covered under this strategy (J. Finney, Fisheries and Oceans Canada, personal
communication).
2.6 SUMMARY OF PREVIOUS STUDIES AT ROBERTS BANK
As described in Archipelago (2009), studies of the subtidal environment at Roberts Bank spanning the
last two decades have included observations of the orange sea pen, particularly in the vicinity of the
northwest corner of Westshore Terminals (Gartner Lee 1992, Golder 1996, Triton 2004).
A large orange sea pen bed was first delineated and mapped in September 2003 by Archipelago (Triton
2004) using a SIMS, or towed underwater video system. Survey results reported a continuous to densely
distributed bed of sea pens covering approximately 15 hectares in the sandy substrate northwest of
Westshore Terminals, from -2.5 to -18 m chart datum (CD) (Triton 2004). A larger area with few to patchy
distribution of sea pens, covering an area of approximately 66 ha, surrounded the dense bed and
extended from -2 to -24 m CD (Triton 2004). Dungeness crab, spiny pink stars (Pisaster brevispinus), and
starry flounder (Platichthys stellatus) were common in the area.
In 2008, Archipelago conducted a follow-up SIMS survey to confirm the sea pen polygons previously
mapped in Triton (2004), and to extend the survey boundaries. Results indicated no change in the
boundaries or depth range of the dense sea pen bed, but indicated a larger area (approximately 114 ha)
of few to patchy sea pens, extending to -35 m CD. Dungeness crabs and flatfish (including starry
flounder) were commonly observed in the area, as were spiny dogfish (Squalus suckleyi)
(Archipelago 2009).
Following the SIMS survey in 2008, Archipelago also conducted a SCUBA survey to collect sea pen
density and community assemblage information. Sea pen density ranged from 0 to 1/m2 (mean= 0.08/m
2)
in the patchy area, and from 1 to 8/m2 (mean= 4.3 /m
2) in the denser area (Archipelago 2009).The dense
site was characterised by silty-sand with 25 to 50% cover of diatoms. Other species associated with the
sea pens at the dense site included, tube dwelling worms, juvenile Dungeness crabs, and flatfish
(predominantly speckled sanddab, Citharichthys sordidus). The patchy site was characterised by silty-
sand with <25% cover of diatoms and associated species included, tube worms, several juvenile crabs, a
sunflower star (Pycnopodia helianthoides), spiny pink stars, and flatfish (predominantly speckled
sanddab). The site with no sea pens was also comprised of silty-sand with some areas of exposed clay
and 25 to 50% cover of diatoms and other observed species included, tube worms, Dungeness crabs,
and flatfish.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 9 - November 2014
3.0 ECOLOGICAL STUDY
The ecological study, conducted in 2011, has two major components:
(i) SIMS Survey; and
(ii) SCUBA Survey.
3.1 STUDY AREA
The study area encompassed areas of the Roberts Bank delta front slope, from the BC Ferries Terminal
in the south to Canoe Passage in the north, including the existing Deltaport dredge basin in the Inter-
causeway Area (Figure 3-1). Minimum depth was the 0 m contour, as orange sea pens are a subtidal
species, while maximum depth was limited by constraints of the SIMS system to approximately -35 m CD.
Sampling effort was highest in the vicinity of the proposed Project as this area houses a large continuous
to densely distributed area of orange sea pens; however, boundaries were expanded to delineate and
map the spatial extent of orange sea pens at Roberts Bank in order to gain a better understanding of the
sub-regional context of this species’ distribution.
3.2 TEMPORAL SCOPE
Sea pens are capable of locomotion such that aggregations are not predictable and have the potential to
show appreciable variation over time. In consideration of such temporal variability, the scope of orange
sea pen studies intends to capture baseline conditions in the study area. Studies build on work dating
back to 2003, and were conducted over a two-year period from 2011 to 2013.
3.3 STUDY METHODS
3.3.1 SIMS Survey Methods & Data Analysis
Archipelago Marine Research Ltd. performed an underwater video survey using SIMS from September 15
to 17, 2011. SIMS is a towed video system developed to carry out systematic mapping of marine
vegetation, macroinvertebrates, seafloor substrates, and morphology from the intertidal zone to depths of
approximately -35 m CD.
The SIMS survey builds on previous SIMS work conducted in the area, with tracklines positioned through
the sea pen polygons mapped in 2003 and 2008 to confirm that sea pens were still present at the
documented locations and in similar densities (Figure 3-2). A grid spacing of 100 x 100 m was used in
the existing sea pen area, and the boundaries were extended approximately 1 km in each direction to the
northwest and southeast. A larger grid size (spacing between 250 m and 750 m) was then used to collect
imagery within the existing dredge basin to 1 km southeast of the BC Ferries Terminal and 5 km
northwest to Canoe Passage (Figure 3-3). The field of view was approximately 1 x 3 m with the camera
maintained at an elevation of 1 to 1.5 m above the seafloor and towed at a speed of about 1 knot
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 10 - November 2014
(2 km/hr). The survey generated 47.7 km of video survey track lines, 19 hours of video imagery, and
ranged in depth from -1.0 to -25 m CD. The depth of previous surveys extended to -35 m CD, which is
reflected in several figures in this report.
Video imagery was classified by an Archipelago biologist in Victoria, B.C., for marine vegetation and
fauna (i.e., crustaceans, anemones, sea stars, and fish) using a standard and biotic classification system
initially developed for the Province of British Columbia (Harper et al. 1998a, b, 1999). The SIMS database
system allows data entry for each second of video imagery collected, permitting the classifier to enter
data every second if biotic features changed.
Orange sea pen distribution was classified according to the codes presented in Table 3-1, and the
interpreted data were imported into ArcView for map production. Maps include point data and polygon
data. Polygon data were determined through visual extrapolation of point data for particular biological
features (e.g., sea pens). As SIMS faunal data is distribution data, densities, as number of organisms per
square area, were not quantified from the SIMS imagery. Other fauna, including crustaceans, sea stars,
anemones, and fish were also classified and mapped.
The categorical distribution data obtained from the SIMS surveys were used to model the influence of sea
pen distribution, depth, and sample year on the distribution of four other faunal groups (crustacean, sea
star, anemones, and fishes) using logistic regression. Four dependent variables, consisting of presence-
absence data for each of the four faunal groups, were analysed separately using the following procedure.
Categorical distribution data from SIMS were converted to presence-absence data for each faunal group,
since distribution codes greater than 1 (“few”; Table 3-1) were rarely recorded. To maintain balance for
model analyses, a commensurate number of absence points were randomly selected to balance each
faunal group presence numbers.
The independent variable, sea pen habitat, was derived from SIMS distribution classifications by
converting to three ordinal categories of sea pen density (i.e., outside the bed, few-patchy distribution, or
continuous-dense distribution), corresponding to the SIMS categories No Observed Fauna, codes 1 and
2 combined, and codes 4 and 5 combined, respectively. While the SIMS surveys did not directly quantify
densities of organisms, the correspondence of the three categories chosen for the logistic regression to
an increasing trend in sea pen densities was confirmed by SCUBA observations (see Section 3.4.2). Data
associated with the SIMS code 3, “uniform” distribution of sea pens, were excluded from the analysis as
these observations were deemed not to be contributing information to densities but only to distribution of
individuals, and their relationship to density had not been investigated by divers. The magnitude of
difference among sea pen categories is not known, and thus the three density categories used for sea
pen habitat were included in the regression model using a flexible step function.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 11 - November 2014
Of the other two independent variables included in the regression model, depth (m relative to CD) was
included as a continuous variable, and sample year (2003, 2008, 2011, and 2012) as a categorical
nominal variable. Individual models for each faunal group were selected based on Akaike’s Information
Criterion (AIC). The best fit models had the fewest parameters within two AIC points of the minimum AIC
score (Burnham and Anderson 2002). Estimation of GLM parameters and model selection were
performed using the statistical package R.
Table 3-1 Faunal Distribution Class Codes for SIMS Bio-classification
Code Descriptor Distribution Example
NOF No fauna observed
1 Few A rare (single) or a few sporadic individuals
2 Patchy A single patch, several individuals, or a few patches
3 Uniform Continuous uniform occurrence
4 Continuous Continuous occurrence with a few gaps
5 Dense Continuous dense occurrence
This page is intentionally left blank.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 12 - November 2014
Figure 3-1 Orange Sea Pen Study Area at Roberts Bank
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 13 - November 2014
Figure 3-2 Towed Underwater Video (SIMS) Tracklines over Time (2003, 2008, 2011) at Roberts Bank
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 14 - November 2014
Figure 3-3 2011 Towed Underwater Video (SIMS) Tracklines and SCUBA Dive Sites at Roberts Bank
This page is intentionally left blank.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 15 - November 2014
3.3.2 SCUBA Survey Methods and Data Analysis
Divers determined orange sea pen density (numbers/m2) and community assemblage information within
three reference areas: i) ‘continuous to dense’ sea pen distribution (SP3); ii) ‘few to patchy’ sea pen
distribution (SP2); and, iii) ‘absent’ sea pens (SP1) (see Figure 3-2; Table 3-2), which were the same
locations surveyed in 2008.
At each dive site, divers established two 6 x 2 m survey grids and used 1 m2 quadrats to count sea pen
density. Six quadrats were counted per grid (i.e., every other square meter was sampled) for a total of
12 quadrats per site. Grids were approximately 3 m apart, and divers worked away from each other such
that the greatest distance of separation was approximately 7 m. A greater distance of separation was not
possible due to reduced visibility and the Work Safe BC regulatory requirement for the two divers to be in
visual contact. At all three survey locations, biophysical features were documented to provide community
assemblage information. Approximately 15 minutes of underwater video imagery were collected at each
survey location.
Mean densities and community assemblage information are qualitatively described and compared among
the three dive sites.
Table 3-2 Summary of the Sea Pen Dive Survey Conducted on Roberts Bank October 19, 2011
Dive Site
Survey Location Description Coordinates
(UTM) Time
Tide Range (m CD)
Depth (m CD)
SP1 West end of SIMS fine survey grid where sea pens were not encountered in previous survey (2008).
N5429593
E485730
12:26 to
12:38 4.1 3.5
SP2 East end of SIMS fine survey grid where sea pen distribution is few to patchy.
N5428978
E487558
10:25 to
10:58 3.8 to 3.9 5
SP3 Center of SIMS fine survey grid where sea pen distribution is continuous to dense.
N5429162
E486869
11:30 to
11:59 4.0 to 4.1 3.5
Note: Depths are reported relative to chart datum.
3.4 RESULTS
3.4.1 SIMS Results
3.4.1.1 Delta Front Slope
Documented orange sea pen habitat at Roberts Bank starts in the Inter-causeway Area and extends
3.5 km northwest, along the delta slope, at depths between -1.5 and -35 m CD. Sea pens are most
prevalent in sandy substrate at depths less than -5 m CD.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 16 - November 2014
Surveys conducted in 2003 and 2008 identified the presence of a large (15 ha) area of continuous to
densely distributed sea pens ranging from -2.5 to -18 m depth CD, which was confirmed in the 2011
survey. Additionally, a second dense aggregation was found on the 2011 survey off the southeast corner
of Westshore Terminals, occupying an area of approximately 7.6 ha, and ranging from -3 to -19 m depth
CD. Combined survey results across years at Roberts Bank yielded 23 ha of densely distributed sea pens
surrounded by 151 ha of sparsely distributed sea pens (Figure 3-4). Sea pens were observed outside the
delineated polygons, but not in high enough densities to be included within the distribution polygons,
accounting for the data points present in Figure 3-4. Photographs are presented in Appendix A.
Sea pens were also documented between -2 to -18 m depth CD in the Inter-causeway Area (including the
existing dredge basin), and east of the BC Ferries Terminal, where trackline spacing was coarser. The
distribution of sea pens was few to patchy within the existing dredge basin east to the survey area
boundary, with some observations of continuous to dense distributions within the Inter-causeway Area at
depths between -2 to -10 m CD. Of note is that mapped distributions are a function of sampling effort
(i.e., trackline spacing and length) and interpolation based on researcher experience and professional
judgement. Additional and/or denser sea pen beds may be present in the area, but were not captured in
this study.
Tracklines were also extended towards Canoe Passage to determine if orange sea pen distribution
reaches further northwest; however, only one sea pen was observed outside the existing polygon in this
direction, indicating limited suitable habitat. Relatively large sand waves and slumped sediment were
documented, suggesting that the substrate may be too unstable for sea pen colonization. An active
commercial crab fishery within documented sea pen areas may also have been a factor in distribution
(Appendix A: Photo 5).
Slope profiles were created along sea pen density gradients (i.e., dense, sparse, absent) to identify areas
along the delta front slope where sea pens tend to congregate (Figure 3-5). The slopes through the
dense portion of the sea pen field were similar for both transects A and B, at m = 0.051 and m = 0.056,
respectively. Sea pens were also sparse or absent along flat slopes (m= 0) and steeper slopes (m> 0.1)
on both transects
Macroinvertebrate species commonly observed within orange sea pen areas included: Dungeness crab,
sunflower stars; spiny pink stars; and plumose anemones (Metridium giganteum) (Figures 3-6 to 3-8).
Flatfish (adult and juvenile), including starry flounder and Pacific sanddab (Citharichthys sordidus), were
also commonly observed, while lingcod (Ophiodon elongatus) and kelp greenling (Hexagrammos
decagrammus) were common on vegetated artificial rock reefs within the sea pen beds off the southern
face of Westshore Terminals (Figure 3-9). All species described in the 2011 survey were also observed
in 2003 and/or 2008 surveys.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 17 - November 2014
3.4.1.2 Existing Dredge Basin
Scattered orange sea pens, few to patchy in distribution, extend into the deepest portion of the existing
dredge basin (-13 to -22 m depth CD). Additionally, they were observed in the northeastern segment of
the existing dredge basin, where they were not documented in 2003; however, the extent of the surveys
was not the same between years so a direct comparison can not be made. Orange sea pens appeared to
be predominantly associated with sandy substrate, although some individuals were found in muddier
substrate.
Within the existing dredge basin, orange sea pens and plumose anemones were the only epibenthic
macroinvertebrate species documented. Mobile macroinvertebrate observations included: scattered
Dungeness crabs; sunflower stars; spiny mud stars (Luidia foliolata); and mottled sea stars (Evasterias
troschelli). Additionally, pandalid shrimp (Pandalus sp.) and a few snails were noted in the shallower
portion of the dredge area, adjacent to the rip-rap of the existing Roberts Bank terminals. A number of fish
were also noted in the rip-rap areas, including lingcod. Bacterial mats (Beggiatoa spp.) were found in the
shallower portions of the dredged area, indicating some hypoxia in the sediments. Native eelgrass
(Zostera marina) was the dominant vegetation observed on the shallowest portions of the mud/sand flats.
All macroinvertebrates, fish, and vegetation described above, with the exception of the orange sea pens,
were also documented in the 2003 SIMS survey.
3.4.1.3 Roberts Bank Overall
A best-fit GLM was selected from a set of models for each faunal group. Table 3-3 summarises the
diagnostic coefficients for each model, while Appendix B presents complete results from the analyses.
Orange sea pen habitat was present in best fit models for all four faunal groups. Depth and sampling year
were included in the best fit models for crustaceans, anemones, and sea stars. Year was not included in
the best fit model for fishes as there were only data for a single year, 2003. Correlation coefficients
indicate the direction of relationship between likelihood of recording presence of a species relative to the
other categories, where higher values indicate a stronger relationship.
Table 3-3 Summary of Predictive Diagnostic Coefficients in the Best-fit Generalised Linear Models for Four Faunal Groups at Roberts Bank
Predictor Variable Crustaceans Sea Stars Anemones Fishes
Intercept (outside sea pen bed) -0.58* -0.43* -3.31* -1.20*
Sea Pen Few to Patchy -0.12 -0.16 1.02* -0.16
Sea Pen Continuous to Dense 3.62* 3.56* 2.39* 2.97*
Year - 2008 -0.04* -0.04* -0.10 -0.04
Year - 2011 -0.28* -0.35* -0.38* N/A
Year - 2012 0.76* 0.65* 2.08* N/A
Depth -0.50* -0.63* 3.72* -0.04*
Notes: * indicates statistical significance (p< 0.05); N/A (not applicable) is assigned where coefficients presented in this table were not used in models for a particular faunal group.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 18 - November 2014
Crustacean presence data were best described by sea pen habitat, depth, and sampling year variables.
Crustacean presence in areas with no sea pens showed a slightly negative association (-0.58; p<0.001),
whereas a positive association (3.62; p<0.001) was observed with continuous dense sea pen habitat.
No significant associations between crustacean presence and areas with few to patchy sea pens
were noted (-0.12; p=0.24). Crustacean presence was also significantly, and slightly negatively,
associated (-0.04; p<0.001) with depth while presence with sampling year was also significant, but varied
from year to year in the direction of the relationship.
Sea star presence was best described by sea pen habitat and year variables. Similar to crustacean and
fish results, areas with no sea pens and areas of continuously to densely distributed sea pens
were significantly associated with sea star presence, showing negative (-0.43; p<0.001) and positive
(3.56; p<0.001) coefficients, respectively. Again, no significant associations between sea star presence
and areas with few to patchy sea pens were noted (-0.16; p=0.11). The association between sea star
presence and sampling year was significant (p< 0.001) but not consistent, which may reflect variation
among year in sampling.
Presence of the anemone group was best described by sea pen habitat, depth, and year variables.
Anemone presence was significantly negatively correlated (-3.31; p<0.001) with areas of no sea pens,
significantly positively associated (1.02; p< 0.001) with areas of few to patchy sea pens, and significantly
positively associated (2.39; p= 0.02) in areas of continuous to dense sea pen distribution. Depth was
significantly and slightly negatively associated (-0.10; p< 0.001) with anemone presence while year varied
in the direction of the relationship. The ordinal regression model results for anemones suggests that there
is a highly significant positive relationship between the distributional abundances of anemones and
sea pens.
Fish presence was best described by sea pen habitat and depth variables. Similar to crustacean results,
areas with no sea pens and areas of continuously to densely distributed sea pens were significantly
associated with fish presence with negative (-1.20; p<0.001) and positive (2.96; p<0.001) coefficients,
respectively. No significant associations between fish presence and areas with few to patchy sea pens
were noted (-0.16; p=0.13). Fish presence was also slightly negatively, but significantly, associated with
depth (-0.04; p<0.001).
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 19 - November 2014
Figure 3-4 Orange Sea Pen Distribution at Roberts Bank
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 20 - November 2014
Figure 3-5 Slope Profiles along Orange Sea Pen Density Gradients
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 21 - November 2014
Figure 3-6 Cumulative Distribution of Crustaceans from SIMS Surveys (2003, 2008, 2011) at Roberts Bank
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 22 - November 2014
Figure 3-7 Cumulative Distribution of Sea Stars from SIMS Surveys (2003, 2008, 2011) at Roberts Bank
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 23 - November 2014
Figure 3-8 Cumulative Distribution of Anemones, Sea Cucumbers, and Snails from SIMS Surveys (2003, 2008, 2011) at Roberts Bank
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 24 - November 2014
Figure 3-9 Cumulative Distribution of Marine Fishes from SIMS Surveys (2003, 2008, 2011) at Roberts Bank
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 25 - November 2014
3.4.2 SCUBA Results
The intent of recording orange sea pen densities by diving rather than SIMS was to obtain better
observational data due to sea pen retraction and expanding behaviour. Dive sites were located in the
shallow, sub-tidal zone at depths of -3.5 to -5.0 m CD, and were selected to overlap with the depths of the
densest portion of the sea pen bed. Data is presented in Table 3-4 (below).
3.4.2.1 Dive Site SP1
Dive Site SP1 was characterised by pronounced sand waves with less than 10% diatom cover and less
than 10% shell debris that consisted of small shell fragments with some small and large half shells
(butter clams (Saxidomus gigantea) and horse clams (Tresus sp.)). The only vegetation observed was
drift eelgrass.
One orange sea pen was observed approximately two metres away from the anchor, but not in any
quadrats. Tube-dwelling worms, likely species of the family Chaetopteridae (three-section tubeworms)
and possibly the family Maldanidae (bamboo worms) were common, but not as abundant as observed at
the other dive sites. Hermit crabs were also common. A few small flatfish (likely a species of sanddab)
less than 5 cm long were observed.
3.4.2.2 Dive Site SP2
Dive Site SP2 was characterised by silty sand with fine wood debris and a 10 to 20% diatom cover.
Scattered shell debris, with some areas of accumulated shell debris (25 to 50% cover), were observed
and consisted of shell fragments as well as small and large half shells. Species that could be identified by
the shells included cockles (Clinocardium sp.), butter clams, and likely horse clams. Drift eelgrass was
also present.
As expected, the distribution of orange sea pens at this survey location was patchy. Densities ranged
from 0 to 2/m2 with an average of 0.42 sea pens/m
2 (n = 12). Most individuals were similar in size,
approximately 30 to 40 cm tall, though some were withdrawn into their peduncle or main polyp and
covered by a layer of silty sand, only identifiable by a slight depression in the substrate (similar to bivalve
siphon depressions). Several smaller sea pens (approximately 10 to 15 cm tall) were observed.
Similar to SP1, tube-dwelling worms were abundant. Dungeness crabs were common, and were
observed moving across the substrate or buried in the sand. Sunflower sea stars and small anemones
attached to shell debris were also observed.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 26 - November 2014
3.4.2.3 Dive Site SP3
Dive Site SP3 was characterised by silty-sand with approximately 40% cover of diatoms. Shell debris
(predominantly small shell fragments and half shells with some large half shells) was scattered
throughout the area, and considered to be less than that observed at SP2 (no areas of accumulated shell
debris observed). From what could be identified, the large half shells were butter clams and horse clams.
The small half shells may be a species of Nutricola (dwarf-venus clam). Round/oval surface depressions
in the seabed suggested bivalve presence; although siphons were not directly observed, some were
observed retracting into the substrate and thought to be horse clams.
As expected, the distribution of orange sea pens at this site was continuous to dense. Densities ranged
from 2 to 13/m2, with an average of 5.7/m
2 (n = 12). Most sea pens appeared to be similar in size,
approximately 30 to 40 cm tall. As observed at SP2, a large proportion of orange sea pens were
withdrawn into their peduncle, some of which were covered by a layer of silty sand and only identifiable
by a slight depression in the substrate.
Similar to the other two dive sites, tube-dwelling worms were abundant. Several Dungeness crabs were
observed either moving across the substrate or buried in the sand. Other biota observed included hermit
crabs, spiny pink stars, and small anemones attached to shell debris. Barnacles were also observed on
the larger shell debris and were actively feeding. A sculpin (family Cottidae) and small shrimp were
observed on one sea pen.
Table 3-4 Sea Pen Density Data for Dive Sites SP2 (sparse) and SP3 (dense) at Roberts Bank on October 19, 2011
Site Diver Depth (m); Time Quadrat # sea pens/m2
SP
2 -
Sp
ars
e
Gina Lemieux
5 m; 10:30 1 0
2 1
3 2
4 1
5 0
5 m; 10:41 6 0
Jamie Smith
5 m; 10:30 1 0
2 0
3 1
4 0
5 0
5 m; 10:42 6 0
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 27 - November 2014
Site Diver Depth (m); Time Quadrat # sea pens/m2
SP
3 -
Den
se
Gina Lemieux
3.5 m; 11:36 1 7
2 2
3 2
4 5
5 7
3.5m; 11:45 6 2
Jamie Smith
3.5 m; 11:34 1 13
2 6
3 4
4 5
5 7
3.5 m; 11:45 6 8
Note: No Sea Pens were Observed in Quadrats at Dive Site SP1 (absent) *Depths are reported relative to chart datum.
3.5 KEY FINDINGS
A discussion of the major results arising from the sea pen ecological study and data gaps is
provided below.
3.5.1 Discussion of Key Findings
SIMS and SCUBA surveys of orange sea pen beds have enhanced the current understanding of the
geographic extent and ecosystem interactions of orange sea pen at Roberts Bank. Results suggest that:
i) the spatial extent of orange sea pens is greater than what has been previously documented;
ii) aggregations of orange sea pens are not reproductively static, as previously understood; iii) there
appears to be a general lack of natural orange sea pen predators; and iv) presence of associated fauna
(crustaceans, sea stars, anemones, and fish) is more likely within areas of continuous to dense sea pens
than areas where distribution is few to patchy or absent.
Prior to 2011, based on 2003 and 2008 SIMS surveys, the mapped extent of orange sea pen distribution
was limited to a large field west of Westshore Terminals. SIMS results from 2011 indicated this area of
continuous to densely distributed sea pens (~15 ha) was unchanged in spatial extent or density. In
addition, the extension of survey boundaries northwest and into the existing dredge basin revealed the
presence of a second dense aggregation (i.e., 7.6 ha in size) at the southern edge of Westshore
Terminals, and scattered individuals in the existing dredge basin. It was not possible to distinguish
whether the increase in spatial extent is a result of a growing population or simply reflective of expanded
survey boundaries and sampling effort.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 28 - November 2014
Previous sea pen studies at Roberts Bank suggested this aggregation was reproductively inactive
because of the absence of smaller sea pens (Hemmera 2009); however, juvenile sea pens (less than
15 cm height) were documented in 2011 (during SIMS and SCUBA surveys). The presence of multiple
size (age) classes in 2011 indicates that these aggregations may represent a breeding population or, at
least, offer conditions favourable for larval settlement, or both. These observations are consistent with
literature that reports larval settlement can be patchy in space and highly episodic in time giving rise to
discontinuous populations differing in age and size (Birkeland 1969, 1974).
Sea pen densities at dive sites SP2 (few to patchy) and SP3 (continuous to dense) increased between
2008 and 2011. At dive site SP2, mean orange sea pen density was higher in 2011 (0.42 sea pens/m2)
than 2008 (0.08 sea pens/m2; n= 12). At dive site SP3 the increase was slighter, from a mean density of
4.3 sea pens/m2
in 2008 to a mean of 5.7 sea pens/m2 in 2011 (n = 12). Natural variation in the number
of sea pens at each location between years is expected, considering dynamic oceanographic conditions,
food availability, seasonality (July versus October), and reproductive strategies. Density differences may
not be biological in origin but instead reflect sea pen retracting behaviour, which makes them
imperceptible and underdetected.
The sea star-nudibranch-sea pen community is based on a known trophic network first described by
Birkeland (1974). Known sea pen predators appear to be largely absent from orange sea pen
aggregations at Roberts Bank, particularly species considered “sea pen specialists” (Birkeland 1974).
This relief from predation pressure may explain, at least in part, how sea pens at Roberts Bank have
been able to achieve such high numbers. Several leather and sunflower stars were observed within the
patchy sea pen polygon, but no nudibranchs have been observed to date. Predation pressure has been
shown to exert considerable influence on local sea pen abundance, with documented mortality rates as
high as 97% from sea star and nudibranch feeding (Birkeland 1974). Predation patterns on sea pens at
Roberts Bank may be different than those reported in Puget Sound studies, or perhaps predation does
not play a major role in influencing sea pen abundance at this particular site.
The role of emergent fauna as physical habitat used by fish populations has been well studied for hard
corals, particularly in tropical environments (Jones and Syms 1998, Auster 2005), but the association of
fishes/macroinvertebrates with sea pens remains largely undefined. Correlations between abundance, or
diversity, of organisms and their habitat have often been used as a measure of the importance of
particular habitat features (Syms and Jones 2001) and the literature provides conflicting views of how
closely coral reef fishes are associated with habitat variables (Jones and Syms 1998). Some authors
have suggested corals are important for mediating fish distribution and abundance (Risk 1972), while
others have demonstrated minimal associations of fishes with corals (Roberts and Ormond 1987, Syms
and Jones 2001).
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 29 - November 2014
At Roberts Bank, significant trends between faunal presence and sea pen distribution were noted for all
groups investigated (i.e., crustaceans, sea stars, anemones, and fish). Year and depth were included as
variables to control for differences in the data collected (e.g., number of samples, locations etc.) and for
differences in sea pen habitat types (“outside” the sea pen bed tends to be shallower), respectively.
Results indicated that the likelihood of presence of each faunal group in continuous to dense sea
pen habitat is significantly higher than in areas of either few to patchy or absent sea pen habitat
(e.g., Photo 3; Appendix A); however, some variation in the direction and magnitude of the likelihood
along the sea pen distribution gradient is likely (i.e., among the three sea pen habitat categories).
Although sea pen beds provide habitat used by a number of other species, there is not enough data to
suggest a functional link between the habitat sea pens provide and demographic patterns of associated
fish and macroinvertebrates. High densities of fishes in aggregations of sea pens do not necessarily
indicate that sea pens provide a unique functional role, rather, they may simply have attributes similar to
other important habitats. In other words, biological and geological habitats may be functionally equivalent
for fish that favour structural relief. For example, Auster et al. (2005) demonstrated the false boarfish
(Neocyttus helgae) used both fan-shaped corals and depressions in basalt pavement habitats as shelter
or flow refuge. Fishes and structural fauna may co-occur in areas of high flows for enhanced prey
delivery but have no direct association, as demonstrated by Tissot et al. (2006) with rockfishes (Sebastes
sp.) in California and Koslow et al. (2000) with orange roughy (Hoplostethus atlanticus) in New Zealand.
While the level of orange sea pen importance in the demography of fish/invertebrate populations and
communities remains to be established, a lack of studies demonstrating functional linkages between
fish/invertebrate and sea pens does not imply that they do not play a role in mediating the distribution and
abundance of associated species. Observations may be missing the time period when particular
fishes/invertebrates (e.g., juveniles, spawners) use such habitats or that use of highly structured habitats
is more spatially constrained or stochastic in nature (Auster 2007).
While the SIMS and SCUBA surveys have enhanced our understanding of the geographic extent and
ecosystem interactions of orange sea pens at Roberts Bank, available information on this species can still
be characterised as relatively data-poor. Similar to what Auster (2007) identified for deep-water corals,
expanded observational studies of sea pens and non-sea pen features as shelter, sources of benthic
prey, and sites with accelerated flows to enhance plankton prey delivery, are required to understand
habitat linkages between orange sea pens, and fish/invertebrate populations and communities.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 30 - November 2014
3.5.2 Data Gaps and Limitations
Gaps in the survey data along the seaward edge of the slope, in deeper waters, exist due to: i) depth limit
of the SIMS system, which was only capable of surveying to approximately 35 m depth; and ii) the
presence of crab traps and commercial seine operations, which made navigation unsafe. Results from a
Remotely Operated Vehicle (ROV) survey confirmed sea pen presence at depths up to -40 m CD
(Hemmera 2014b), indicating that the full extent of sea pen distribution at Roberts Bank (including
southeast to Point Roberts) remains undetermined.
The only literature available to compare to Roberts Bank sea pen density data is estimates from Puget
Sound in the 1960s where Birkeland (1968, 1974) recorded densities of up to 22 sea pens/m2 in depths of
-10 to -25 m. Sea pen density is notoriously difficult to estimate, as adult individuals tend to retract into
their peduncle and can become completely unnoticeable. Caution is warranted in interpreting density
results because it is difficult to accurately determine how many or what proportion of individuals are
buried, leading to underestimation of abundance and density. Nevertheless, this study was able to meet
the objectives of estimating the spatial distribution and density of sea pens at Roberts Bank, and
documenting species associations.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 31 - November 2014
4.0 LOCAL KNOWLEDGE STUDY
This section presents the methods and results of the orange sea pen local knowledge study.
4.1 STUDY METHODS
In an attempt to better understand the life history, spatial extent, and ecological importance of orange sea
pens, a local ecological knowledge survey was developed and distributed to select individuals during
January 2013. People with relevant direct knowledge, whether from a natural history or
scientific/ecological analysis perspective, were identified based on desktop research and specific collegial
referrals. Participants included academics, dive shop/tourism operators, fishermen, and aquarists.
Individuals were presented with a brief explanation of the proposed Project, the rationale and objectives
of the questionnaire, and a request for participation in contributing their local knowledge. Approximately
85 individuals or organizations were contacted to participate in completing the questionnaire, of which
43 responses were received (51% response rate). Of the responses received, 31 individuals, henceforth
referred to as ‘the participants’ contributed information specific to orange sea pens whether directly in the
questionnaire or via email explanation, or by providing detailed data. Many of the remaining 12 responses
did not contain information specific to orange sea pens but provided other useful information such as
referrals to those who may be better-suited to provide relevant information.
The survey was structured so that questions pertaining to orange sea pens were presented in as logical
and comprehensible a manner as possible. The four-page questionnaire was comprised of four sections
with a total of 20 questions specific to orange sea pen life history, spatial extent, and role in supporting
other marine species and ecological functions. The questionnaire was organised based on the following
subjects:
Geographical range and ecological significance;
Abiotic drivers;
Ascribed value; and
Further information.
Appendix C provides a list of participants, list of questions and documented responses.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 32 - November 2014
4.2 RESULTS
4.2.1 Geographical Range and Ecological Significance
4.2.1.1 Species Distribution
Participants were asked to list and/or describe areas where they know orange sea pens exist. Responses
corroborated what is reported in the literature and indicate that orange sea pens range from Alaska to
California (Figure 4-1). Responses varied in terms of specificity, with some pointing to general coastal
regions, while others pinpointed precise locations. Locally, in and around the Strait of Georgia, there were
numerous accounts of orange sea pens in the Gulf Islands, Puget Sound, and Howe Sound (Figure 4-2).
4.2.1.2 Observed Densities
Participants were asked if they have observed dense aggregations of orange sea pens (defined as >four
individuals/m2) and whether they would consider such aggregations to be a unique habitat feature. Of the
25 participants who directly observed orange sea pen aggregations along the Pacific Northwest coast,
16 individuals indicated that they had observed densities of >four individuals per m2
whereas 9 individuals
had only observed densities of <four individuals per m2.
Most participants who observed dense aggregations (>four individuals per m2) considered them to be a
unique habitat feature of the area. Several responses indicated that orange sea pens can be a dominant
feature on the seafloor, supporting the presence of other species that would not be there otherwise, thus
contributing to overall species diversity; however, some participants did not consider sea pen
aggregations particularly unique, citing that they occur at a number of locations under a variety of biotic
and abiotic conditions
Several participants emphasised the difficulty in accurately estimating orange sea pen densities due to
the species’ ability to bury into the surrounding sediment; consequently, examination of a site by divers
tends to underestimate sea pen abundance and/or density.
4.2.1.3 Ecologically-Linked Species
Participants were asked whether they typically observe any fish or invertebrate species associated with
orange sea pens. Most responses included nudibranchs and sea stars (known predators of orange sea
pens). Other frequently observed species included, Dungeness, red rock (Cancer productus), and
graceful rock (Metacarcinus gracilis) crabs, copper (Sebastes caurinus) and quillback (Sebastes maliger)
rockfish, flatfish including starry flounder, and English (Parophrys vetulus) and C-O sole (Pleuronicthys
coenosus), and geoduck clams. Participants were also asked to comment on whether they believe these
species associations to be coincidental, or whether the species interact with one another. The most
common response pointed to the role of orange sea pens as key prey items for certain species of
nudibranch and sea stars. Multiple participants indicated that mobile species, such as crabs, rely on sea
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 33 - November 2014
pen beds for shelter/refuge while others deemed this relationship coincidental as they do not eat the pens
or require their shelter. The geoduck–orange sea pen association; however, was considered to be
coincidental as the species are thought to share the same habitat preferences but not interact.
Participants were then asked whether they have observed predators near orange sea pen colonies. Of
the 24 participants that answered this question, 16 individuals indicated that they have directly observed
nudibranchs preying on orange sea pens (particularly Tritonia diomedea, Tritonia festiva, and Armina
californica). Many participants have also observed certain species of sea star (particularly Hippasteria
spp.) feeding both on sea pens and on nudibranchs.
4.2.2 Abiotic Drivers
4.2.2.1 Substrate Type
Participants were asked to identify what type of substrate(s) orange sea pens prefer, based on their
experience. There was consensus around sand being a preferred substrate, with all participants
indicating they have observed orange sea pens in sand. The range of answers indicated that orange sea
pens are commonly found in substrates ranging from silt-mud to sand-cobble with shell debris; however,
several responses emphasised that orange sea pens are not found in silty habitats.
4.2.2.2 Flow
Participants were asked to describe the flow conditions in which they typically find orange sea pens.
The majority of answers indicated sea pens are associated with moderate to high flow environments, with
strong currents. One answer made the point that the largest colonies are always in areas of moderate to
high current, and that the density drops off moving away from the current stream. Other answers
indicated that orange sea pens can also be found in low-flow environments.
4.2.2.3 Depth
When asked what depth range they observe orange sea pens within, most participants answered
between -5 to -30 m CD, but that they do occur deeper, commonly to -50 m. Several participants pointed
out that the range identified may be limited to those depths accessible by SCUBA.
4.2.2.4 Unique Habitat Attributes
Participants were asked to describe any unique attributes of the surrounding environment where they
observed orange sea pens, such as freshwater outflows. Approximately half of the participants noted that
they have often found orange sea pens in estuarine habitats or other areas where freshwater sources are
common. One participant made the point that while a number of known sea pen beds have nearby fresh
water input, the work has not been done to establish that sites without freshwater input, but all the other
substrate and flow characteristics, are less likely to have sea pens. The remaining half of participant
answers indicated that they have not observed orange sea pens in the vicinity of freshwater outflows, or
any other defining habitat attributes.
This page is intentionally left blank.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 34 - November 2014
Figure 4-1 Anecdotal Sea Pen Observations along the Pacific Coast
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 35 - November 2014
Figure 4-2 Anecdotal Sea Pen Observations in the Strait of Georgia
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 36 - November 2014
4.2.2.5 Significance of Abiotic Factors
Participants commented on whether they believe that any of the previously-mentioned abiotic factors
dictate where orange sea pens choose to aggregate. Sandy substrate and the presence of moderate to
strong currents were identified as the main factors that likely drive aggregation locations; however,
several participants indicated that a combination of these abiotic factors dictates location choice.
One response indicated that, while sandy sediments are obviously the preferred sediment type, because
individuals and low density populations occur in a variety of sediment types (ranging from silt to gravel
pockets), this is not an absolute habitat-controlling factor. Another response suggested the patchy
distribution of orange sea pens indicates that some factors might be favourable for targeting settlement,
and that chemical cues from conspecifics (i.e., existing sea pens), along with substrate cues and possibly
flow cues, might all contribute.
4.2.2.6 Additional Abiotic Factors
Participants commented on whether they were aware of, or have any hypotheses pertaining to, additional
abiotic environmental characteristics that may control orange sea pen distribution and fitness. Possible
hypotheses included salinity fluctuations, nutrient input (insofar as it affects plankton), light, and depth.
4.2.3 Ascribed Value
4.2.3.1 Ecosystem Functions
Participants commented on whether they have any hypotheses regarding important ecosystem functions
(i.e., physical, chemical, and biological processes/attributes that contribute to the ecosystem) provided by
colonies of orange sea pens. Many participants indicated that sea pens play a vital role as ecological
engineers in that they turn over and oxygenate sediments through their burying behaviour, provide habitat
structure and heterogeneity, and influence current flow over the substrate. The strong effects that sea
pens might have on phytoplankton and sustaining food webs through nutrient cycling was also
hypothesised by various participants.
4.2.3.2 Anthropogenic Value
Although most participants indicated that orange sea pens do not hold any specific role in their
culture/lifestyle, every participant indicated that there is value in knowing that the species simply exists
(existence value) and elaborated upon the concept of intrinsic value of biodiversity. Multiple participants
indicated that, although the roles that orange sea pens play in the ecosystem are poorly understood, it
does not make them unimportant. Several responses highlighted that these are fascinating and beautiful
organisms that are a favorite amongst recreational divers.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 37 - November 2014
4.2.3.3 Additional Comments
When participants were asked if there is any other information regarding P. gurneyi that they would like to
contribute, 13 participants offered responses. Nine of the responses provided references to relevant
contacts or journal articles. The remaining four responses, presented below, pertained to persistence of
the species, highlighting both natural and anthropogenic causes for observed declines:
“Beds don't seem to be a stable feature. They seem to persist for a couple decades and
eventually get wiped out by predators; in the meantime new beds pop up (and many blink out
while still juveniles) but some eventually take hold. I think many of the juvenile beds succumb to
non-specialist predators like Hermissenda.”
- Dr. Greg Jensen, University of Washington
“Sea pens have been declining in Puget Sound. Some researchers who used to work on them
there (e.g., near Golden Gardens State Park in Seattle) can’t find them in such abundance, if at
all. I’m not sure if that is also true in the Strait of Georgia, but it does at least suggest that this
species might be one of conservation concern.”
- Dr. Chris Harley, University of British Columbia.
“It is notable that Birkeland(1968:10) stated ‘In general, then, Ptilosarcus is never sparse.’
This statement was verified by Birkeland at a number of locations in Puget Sound. Thus, it is
somewhat alarming that since approximately 1980, I have found the P. gurneyi populations in all
of Birkeland’s original study areas to be sparse and only a relatively small fraction of their original
density (Kyte 2001). However, the population that I recently observed on the west side of Ketron
Island in South Puget Sound appeared to be nearly as dense as those studied by Birkeland.
The only other location that may have dense P. gurneyi populations is Dash Point near Tacoma,
Washington.”
- Michael Kyte, Senior Marine Biologist.
“It is really important to realise how little is known about the species, how important its biomass is,
that it seems to be a key prey item to multiple species, that it is often in the shallows where it is
particularly susceptible to the impacts of urbanization (chemical, physical disturbance), and – that
research indicates it needs low flow areas whereby any development impacting flow is highly
likely to have an impact (again particular susceptibility in the shallows).”
- Jackie Hildering, Diver.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 38 - November 2014
5.0 CLOSURE
Major authors and reviewers of this technical data report are listed below, along with their signatures.
Report prepared by: Hemmera Envirochem Inc.
Marina Winterbottom, Master of Marine Management Marine Biologist Archipelago Marine Research
Pamela Thuringer, M.Sc., R.P.Bio. Marine Biologist Report peer reviewed by: Hemmera Envirochem Inc.
Jamie Slogan, M.Sc., PhD (cand.), R.P.Bio. Senior Marine Biologist
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 39 - November 2014
6.0 REFERENCES
Archipelago. 2009. Section 10: Seapen bed interpretation; Section 11; Lingcod egg mass survey. In:
Hemmera 2009. T2 Environmental Baseline Montoring Report. Prepared for Vancouver Port
Authority. Vancouver, B.C.
Auster, P. J. 2005. Are deep-water corals important habitats for fishes? Pages 747–760 in. Cold-water
corals and ecosystems. Springer Berlin Heildelberg.
Auster, P. J. 2007. Linking deep-water corals and fish populations. Bulletin of Marine Science 81:93–99.
Beaulieu, S. 2001. Life on glass houses: sponge stalk communities in the deep sea. Marine Biology
138:803–817.
Bell, S. S. 1985. Habitat complexity of polychaete tube-caps: influence of architecture on dynamics of a
meioepibenthic assemblage. Journal of Marine Research 43:647–671.
Best, B. A. 1988. Passive suspension feeding in a sea pen: effects of ambient flow on volume flow rate
and filtering efficiency. The Biological Bulletin 175:332–342.
Birkeland, C. 1968. Reciprocal interactions between a single prey species, Ptilosarcus gurneyi, and its
complex of predators. Thesis, University of Washington, Seattle.
Birkeland, C. 1969. Consequences of differing reproductive and feeding strategies for the dynamics and
structure of an association based on the single prey species, Ptilosarcus gurneyi (Gray).
Disertation, University of Washington, Seattle.
Birkeland, C. 1974. Interactions between a sea pen and seven of its predators. Ecological Monographs
44:211–232.
Boutillier, J. A., E. Kenchington, and J. Rice. 2010. A review of the biological characteristics and
ecological functions served by corals, sponges and hydrothermal vents, in the context of applying
an ecosystem approach to fisheries. DFO Canadian Science Advisory Secretariat Research
Document.
Buhl-Mortensen, L., and P. B. Mortensen. 2004. Crustaceans associated with the deep-water gorgonian
corals Paragorgia arborea (L., 1758) and Primnoa resedaeformis (Gunn., 1763). Journal of
Natural History 38:1233–1247.
Buhl‐Mortensen, L., A. Vanreusel, A. J. Gooday, L. A. Levin, I. G. Priede, P. Buhl‐Mortensen, H.
Gheerardyn, N. J. King, and M. Raes. 2010. Biological structures as a source of habitat
heterogeneity and biodiversity on the deep ocean margins. Marine Ecology 31:21–50.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 40 - November 2014
Burd, B. J., P. A. G. Barnes, C. A. Wright, and R. E. Thomson. 2008. A review of subtidal benthic habitats
and invertebrate biota of the Strait of Georgia, British Columbia. Marine Environmental Research
66:S3–S38.
Burnham, K. P., and D. R. Anderson. 2002. Model selection and multimodel inference: a practical
information-theoretic approach. Second Edition. Springer-Verlag, Berlin.
Chia, F. S., and B. J. Crawford. 1973. Some observations on gametogenesis, larval development and
substratum selection of the sea pen Ptilosarcus gurneyi. Marine Biology 23:73–82.
Colpron, E., E. N. Edinger, and B. Neis. 2010. Mapping the distribution of deep-sea corals in the Northern
Gulf of St. Lawrence using both scientific and local ecological knowledge. Canadian Science
Advisory Secretariat (DFO).
Davis, N., and G. R. VanBlaricom. 1978. Spatial and temporal heterogeneity in a sand bottom epifaunal
community of invertebrates in shallow water. Limnology and Oceanography 23:417–427.
DFO (Fisheries and Oceans Canada). 2007. Ecosystem overview: Pacific North Coast Integrated
Management Area (PNCIMA). Edited by B.G. Lucas, S.M. Verrin, R. Brown for Canadian
Technical Report of Fisheries and Aquatic Sciences.
DFO (Fisheries and Oceans Canada). 2011. Pacific Region cold-water coral and sponge conservation
strategy (2010-2015). Fisheries and Oceans Canada.
DFO (Fisheries and Oceans Canada). 2012. Assessment of the impact of northern shrimp trawling on
benthic habitats and communities in the estuary and northern Gulf of St. Lawrence. Science
Advisory Report, Canadian Science Advisory Secretariat, Quebec Region.
Diaz, R., G. Cutter, and K. Able. 2003. The importance of physical and biogenic structure to juvenile
fishes on the shallow inner continental shelf. Estuaries 26:12–20.
Dickinson, P. 1978. Conduction systems controlling expansion-contraction behaviour in the seapen
Ptilosarcus gurneyi. Marine Behaviour and Physiology 5:163–183.
Edinger, E. N., V. E. Wareham, and R. L. Haedrich. 2007. Patterns of groundfish diversity and abundance
in relation to deep-sea coral distributions in Newfoundland and Labrador waters. Bulletin of
Marine Science 81:101–122.
Edwards, D., and C. Moore. 2008. Reproduction in the sea pen Pennatula phosphorea (Anthozoa:
Pennatulacea) from the west coast of Scotland. Marine Biology 155:303–314.
Erhardt, H., and H. Moosleitner. 1998. Baensch Marine Atlas 2. Microcosm Ltd.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 41 - November 2014
FAO. 2008. Report of the technical consultation on international guidelines for the management of deep-
sea fisheries in the high seas. Fisheries and Aquaculture Report, United Nations Food and
Agriculture Organization, Rome, Italy.
Field, J. M., M. Yoklavich, J. Marignac, G. Caillet, R. Lea, and S. Bros. 2001. Deepwater habitat and fish
resources associated with a marine reserve: implications for fisheries: Part II. Marine Ecological
Reserves Research Program.
Fuller, S. D., F. J. Murillo Perez, V. Wareham, and E. Kenchington. 2008. Vulnerable marine ecosystems
dominated by deep-water corals and sponges in the NAFO Convention area. Northwest Atlantic
Fisheries Organization.
Gartner Lee. 1992. Environmental appraisal of proposed container terminal, Roberts Bank. Prepared for
Vancouver Port Corporation.
Golder. 1996. Marine environmental review of a proposed grain terminal at Roberts Bank. Report for
Vancouver Port Corporation.
Goodwin, C., and B. Pease. 1991. Geoduck, Panopea abrupta (Conrad, 1849), size, density, and quality
as related to various environmental parameters in Puget Sound, Washington. Journal of Shellfish
Research 10:65–77.
Gotshall, D., and L. L. Laurent. 1979. Pacific Coast subtidal marine invertebrates: A fishwatcher’s guide.
Sea Challengers.
Harper, J. R., B. D. Bornhold, P. Thuringer, and D. McCullough. 1999. Application of underwater video
imaging for seabed Engineering and habitat assessment. In proceedings of the 1999 Canadian
Coastal Conference, Victoria, B.C.
Harper, J. R., B. Emmett, D. E. Howes, and D. McCullough. 1998a. Seabed imaging and mapping system
- seabed classification of substrate, epiflora, and epifauna. In proceedings of the 1998 Canadian
Hydrographic Conference, Victoria, B.C.
Harper, J. R., D. McCullough, B. Emmett, P. Thuringer, and A. Ledwon. 1998b. Seabed imaging and
mapping system - pilot project results. Land Use Coordination Office, Victoria, B.C.
Heifetz, J. 2002. Coral in Alaska: distribution, abundance, and species associations. Hydrobiologia
471:19–28.
Hemmera. 2014a. Roberts Bank Terminal 2 technical report: Habitat suitability modelling study. Prepared
for Port Metro Vancouver, Vancouver, B.C. in Port Metro Vancouver (PMV). 2015. Roberts Bank
Terminal 2 Environmental impact statement: Volume 3. Environmental Assessment by Review
Panel. Submitted to Canadian Environmental Assessment Agency..
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 42 - November 2014
Hemmera. 2014b. Roberts Bank Terminal 2 technical data report: Marine invertebrates, marine fish & fish
habitat - Marine benthic subtidal study. Prepared for Port Metro Vancouver, Vancouver, B.C.
Available at: http://www.robertsbankterminal2.com/
Hixon, M. A., and B. N. Tissot. 2007. Comparison of trawled vs untrawled mud seafloor assemblages of
fishes and macroinvertebrates at Coquille Bank, Oregon. Journal of Experimental Marine Biology
and Ecology 344:23–34.
Hughes, D. 1998. Sea pens and burrowing megafauna (Volume III). An overview of dynamic and
sensitivity characteristics for conservation and management of marine SACs. Scottish
Association for Marine Science (UK Marine SACs Project).
Jones, G. P., and C. Syms. 1998. Disturbance, habitat structure and the ecology of fishes on coral reefs.
Australian Journal of Ecology 23:287–297.
Kenchington, E., H. Link, V. Roy, P. Archambault, T. Siferd, M. Treble, and V. Wareham. 2011.
Identification of Mega- and Macrobenthic Ecologically and Biologically Significant Areas (EBSAs)
in the Hudson Bay Complex, the Western and Eastern Canadian Arctic. DFO Canadian Science
Advisory Secretariat Research Document.
Koslow, J., G. Boehlert, J. Gordon, R. Haedrich, P. Lorance, and N. Parin. 2000. Continental slope and
deep-sea fisheries: implications for a fragile ecosystem. ICES Journal of Marine Science: Journal
du Conseil 57:548–557.
Kozloff, E. 1993. Seashore life of the northern Pacific Coast. University of Washington Press, Seattle.
Kyte, M. A. 2001. Vacant benthic habitats: where have all the sea pens gone? Pacific Estuarine Research
Society.
Lamb, A., and B. P. Hanby. 2005. Marine life of the Pacific Northwest: a photographic encyclopedia of
invertebrates, seaweeds and selected fishes. Harbour Publishing, Madeira Park, B.C.
Levin, L. A., and P. K. Dayton. 2009. Ecological theory and continental margins: where shallow meets
deep. Trends in Ecology & Evolution 24:606–617.
Malecha, P. W., R. P. Stone, and J. Heifetz. 2005. Living substrate in Alaska: distribution, abundance,
and species associations. Page 289 in. Volume 41. American Fisheries Society.
NOAA. 2010. Implementation of the Deep Sea Coral Research and Technology Program 2008-2009.
Report to Congress.
NOAA. 2011. NOAA Fisheries Service. Habitat Conservation Division. <http://www.nmfs.noaa.gov/>.
Accessed 2 Nov 2011.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 43 - November 2014
OSPAR. 2010. Background document for sea pen and burrowing megafauna communities. Biodiversity
Series.
Pirtle, J. L. 2005. Habitat-based assessment of structure-forming megafaunal invertebrates and fishes on
Cordell Bank, California. Thesis, Washington State University.
Risk, M. J. 1972. Fish diversity on a coral reef in the Virgin Islands. Smithsonian Institution.
Roberts, C., and R. Ormond. 1987. Habitat complexity and coral reef fish diversity and abundance on
Red Sea fringing reefs. Marine Ecology Progress Series. Oldendorf 41:1–8.
Ryer, C. H., A. W. Stoner, M. L. Spencer, and A. A. Abookire. 2007. Presence of larger flatfish modifies
habitat preference by Age-0 northern rock sole Lepidopsetta polyxystra. Marine Ecology Progress
Series 342:227–238.
Ryer, C. H., A. W. Stoner, and R. H. Titgen. 2004. Behavioral Mechanisms Underlying the Refuge Value
of Benthic Habitat Structure for Two Flatfishes with Differing Anti-Predator Strategies. Marine
Ecology Progress Series 268:231 – 243.
Shimek, R. L. 2011. The life and death of sea pens. Reefkeeping Magazine 1–19. Available at
http://reefkeeping.com/issues/2005-08/rs/feature/index.php
Soong, K. 2005. Reproduction and colony integration of the sea pen Virgularia juncea. Marine Biology
146:1103–1109.
Stoner, A. W., M. L. Spencer, and C. H. Ryer. 2007. Flatfish-habitat associations in Alaska nursery
grounds: use of continuous video records for multi-scale spatial analysis. Journal of Sea
Research 57:137–150.
Syms, C., and G. P. Jones. 2001. Soft corals exert no direct effects on coral reef fish assemblages.
Oecologia 127:560–571.
Tissot, B. N., M. S. Love, K. York, and M. Amend. 2006. Benthic invertebrates that form habitat on deep
banks off southern California, with special reference to deep sea coral. Fishery Bulletin 104:167–
181.
Triton. 2004. Deltaport Third Berth Project: Marine resources impact assessment. Triton Environmental
Consultants Ltd., Richmond, B.C. Prepared for Vancouver Port Authority.
WoRMS. 2008. WoRMS taxon details: Ptilosarcus. World Register of Marine Species.
Port Metro Vancouver Hemmera RBT2 – Orange Sea Pens - 44 - November 2014
7.0 STATEMENT OF LIMITATIONS
This report was prepared by Hemmera Envirochem Inc. ("Hemmera") and Archipelago Marine Research
("Archipelago"), based on fieldwork conducted by Hemmera and Archipelago, for the sole benefit and
exclusive use of Port Metro Vancouver. The material in it reflects the authors' best judgment in light of the
information available to them at the time of preparing this Report. Any use that a third party makes of this
Report, or any reliance on or decision made based on it, is the responsibility of such third parties.
Hemmera and Archipelago accept no responsibility for damages, if any, suffered by any third party as a
result of decisions made or actions taken based on this Report.
Hemmera and Archipelago have performed the work as described above and made the findings and
conclusions set out in this Report in a manner consistent with the level of care and skill normally
exercised by members of the environmental science profession practicing under similar conditions at the
time the work was performed.
This Report represents a reasonable review of the information available to Hemmera and Archipelago
within the established Scope, work schedule and budgetary constraints. The conclusions and
recommendations contained in this Report are based upon applicable legislation existing at the time the
Report was drafted. Any changes in the legislation may alter the conclusions and/or recommendations
contained in the Report. Regulatory implications discussed in this Report were based on the applicable
legislation existing at the time this Report was written.
In preparing this Report, Hemmera and Archipelago have relied in good faith on information provided by
others as noted in this Report, and have assumed that the information provided by those individuals is
both factual and accurate. Hemmera and Archipelago accept no responsibility for any deficiency,
misstatement or inaccuracy in this Report resulting from the information provided by those individuals.
APPENDIX A
Photographs
Port Metro Vancouver APPENDIX A Hemmera RBT2 – Orange Sea Pens - 1 - November 2014
Photo 1: Sparse to Patchy Distribution of Sea Pens
Photo 2: Continuous to Dense Distribution of Sea Pens
Port Metro Vancouver APPENDIX A Hemmera RBT2 – Orange Sea Pens - 2 - November 2014
Photo 3: Dungeness Crab Hiding Under Orange Sea Pen
Photo 4: Retracted Sea Pens Indicated by Red Arrows
Port Metro Vancouver APPENDIX A Hemmera RBT2 – Orange Sea Pens - 3 - November 2014
Photo 5: Orange Sea Pens with Crab Trap
Photo 6: Juvenile Sea Pens Indicated by Red Arrows
APPENDIX B
Statistical Summaries
Port Metro Vancouver APPENDIX B Hemmera RBT2 – Orange Sea Pens - 1 - November 2014
Predictor Variable Predictive Diagnostic
Coefficient Std. error z value p value
Crustaceans
Intercept (outside sea pen bed) -0.58 0.07 -8.59 < 0.001
Sea Pen Few to Patchy -0.12 0.10 -1.18 0.24
Sea Pen Continuous to Dense 3.62 0.72 5.02 < 0.001
Year - 2008 -0.28 0.12 -2.35 0.02
Year - 2011 0.76 0.09 8.11 < 0.001
Year - 2012 -0.50 0.14 -3.63 < 0.001
Depth -0.04 0.00 -9.03 < 0.001
Sea Stars
Intercept (outside sea pen bed) -0.43 0.06 -6.70 < 0.001
Sea Pen Few to Patchy -0.16 0.10 -1.60 0.11
Sea Pen Continuous to Dense 3.56 0.72 4.94 < 0.001
Year - 2008 -0.35 0.12 -2.98 0.00
Year - 2011 0.65 0.09 6.99 < 0.001
Year - 2012 -0.63 0.14 -4.57 0.00
Depth -0.04 0.00 -8.42 < 0.001
Anemones
Intercept (outside sea pen bed) -3.31 0.16 -20.29 < 0.001
Sea Pen Few to Patchy 1.02 0.12 8.86 < 0.001
Sea Pen Continuous to Dense 2.39 1.04 2.30 0.02
Year - 2008 -0.38 0.20 -1.85 0.07
Year - 2011 2.08 0.16 12.92 < 0.001
Year - 2012 3.72 0.17 21.43 < 0.001
Depth -0.10 0.01 -14.78 < 0.001
Fishes
Intercept (outside sea pen bed) -1.20 0.07 -18.36 < 0.001
Sea Pen Few to Patchy -0.16 0.11 -1.51 0.13
Sea Pen Continuous to Dense 2.97 0.76 3.92 < 0.001
Depth -0.04 0.00 -9.17 < 0.001
APPENDIX C
Local Knowledge Survey Questionnaire and Results
ECOLOGICAL KNOWLEDGE QUESTIONNAIRE – ORANGE SEA PEN (PTILOSARCUS GURNEYI)
OBJECTIVE OF QUESTIONNAIRE:
On behalf of Port Metro Vancouver, Hemmera is seeking local knowledge pertaining to the marine fauna
surrounding the proposed Roberts Bank Terminal 2 project in British Columbia. You have been identified
as a participant based on a desktop study that identified individuals possessing relevant expertise,
experience and/or knowledge in this particular field of study. Specifically, Hemmera is seeking your input
in regard to known Orange Sea Pen (Ptilosarcus gurneyi) aggregations throughout the Pacific Northwest.
P. gurneyi are sessile colonial octocorals found in predominantly sub-tidal sandy bottom habitats (to over
100m) from southern California to Alaska (Gotshall and Laurent 1979). They are long lived species (to
over 15 years) and they exhibit a spatially clumped pattern of recruitment(Birkeland 1974). Adult sea pens
have the ability to retract into the sand at times becoming completely undetectable.
Although P. gurneyi has been documented sporadically along the west coast of Canada and the United
States of America, limited current information exists regarding details on exactly where these
invertebrates are found and their densities. Furthermore, studies describing the ecological importance of
sea pen beds in near shore environments are lacking.
In an attempt to better understand the life history, spatial extent and ecological importance of P. gurneyi,
we ask you to please take a moment to fill out the following survey to the best of your ability.
PART A. GEOGRAPHICAL RANGE AND ECOLOGICAL SIGNIFICANCE
1. Are you familiar with the orange sea pen, Ptilosarcus gurneyi?
▫ No (Please continue to Part D)
▫ Yes
2. Please describe the area along the Pacific Northwest coast in which you are familiar with P.
gurneyi.
3. Please explain how you are familiar with P. gurneyi and the methods by which you have gathered
information on them (e.g., direct dive surveys, studies of sea pens in lab setting, bycatch of sea
pens in trawl gear, etc.).
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 2 - November 2014
4. Have you observed P. gurneyi directly??
▫ No (Please continue to Part C)
▫ Yes, in aggregations of < 4 individuals per m2
▫ Yes, in aggregations of > 4 individuals per m2
5. If you observed a dense aggregation of P. gurneyi (i.e. > 4 individuals per m2), would you
consider this to be a unique habitat feature of the area? Please explain why and describe the
density of the P. gurneyi aggregation that you observed (#’s per m2).
6. Did you observe juvenile fish or invertebrate species (e.g., rockfish, geoducks, shrimp, crabs)
associated with P. gurneyi? Identified species can be associated with both small (<4 / m2) and
large (>4 / m2) P. gurneyi aggregations. Please provide a description of associated species.
▫ No
▫ Yes
i. ______________________________________________
ii. ______________________________________________
iii. ______________________________________________
7. Do you believe the above mentioned species associations to be coincidental? (i.e. both species
simply prefer the same habitat)OR do you believe that these species have important interactions
between one-another? (i.e. juvenile fish rely on sea pens as a refuge from predators)? Please
explain.
8. Did you observe predators (i.e. nudibranchs and sea stars) near P. gurneyi colonies? Please
describe interaction.
PART B. ABIOTIC (NON-LIVING) FACTORS
9. Were observed P. gurneyi found in sandy substrate? Please explain the observed substrate type.
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 3 - November 2014
10. Have you found P. gurneyi in high flow environments? Please explain.
11. At what depth range did you observe P. gurneyi?
12. Please describe any unique attributes of the surrounding environment where you observed P.
gurneyi. Specifically, please comment on any freshwater outflows that may have been present in
the vicinity.
13. Do you believe that any of the previously-mentioned abiotic (non-living) factors dictate where P.
gurneyi choose to aggregate? Please explain.
14. Are you aware of, or have any hypotheses regarding additional abiotic (non-living) environmental
characteristics that may control P. gurneyi distribution and fitness?
PART C. ASCRIBED VALUE
15. Do P. gurneyi (or sea pens in general) hold any specific traditional or cultural role for you? Please
explain.
16. Is it important for you to know that P. gurneyi (or sea pens in general) simply exist, even if they do
not play a role in your culture/lifestyle (i.e. existence value)? Please explain.
17. Are you aware of, or have any hypotheses regarding important ecosystem functions (physical,
chemical, and biological processes/attributes that contribute to the ecosystem) attributable to
aggregations of P. gurneyi?
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 4 - November 2014
PART D. FURTHER INFORMATION
18. Do you know of others who may be knowledgeable about P. gurneyi (or sea pens in general)
along the Pacific Northwest coast? If yes, could you please provide their name and/or contact
information?
▫ No
▫ Yes, please find name and/or contact information below:
_____________________________________
_____________________________________
_____________________________________
_____________________________________
19. May we contact you via telephone to further discuss your knowledge regarding P. gurneyi?
▫ No thank you, I do not wish to be contacted further.
▫ Yes, you may contact me at the following number:
_____________________________________
20. Is there any other information regarding P. gurneyi that you would like to add? Please explain.
Thank you for taking the time to complete this survey on Ptilosarcus gurneyi.
Your input is much appreciated.
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 5 - November 2014
Table 1 Orange Sea Pen Local Ecological Knowledge Participant Information
# Name Organization Email
1 Dr. David Arsenault Bamfield Marine Science Center [email protected]
2 Dr. Charles Birkeland University of Hawaii [email protected]
3 Dr. Thomas Carefoot University of British Columbia emeritus [email protected]
4 Jim Cosgrove Royal BC Museum [email protected]
5 Dr. David Cowles Walla Walla University [email protected]
6 John DeBoeck Diver, Dive Industry Association of BC [email protected]
7 Dr. Barb Faggetter Ocean Ecology [email protected]
8 Donna Gibbs Vancouver Aquarium [email protected]
9 Dr. Chris Harley University of British Columbia [email protected]
10 Dr. Chris Harvey-Clark University of British Columbia [email protected]
11 Jackie Hildering Diver, Earthling Enterprises [email protected]
12 Dr. Greg Jensen University of Washington [email protected]
13 Chad King NOAA [email protected]
14 Michael Kyte Marine Biologist, The Talley Group [email protected]
15 Andy Lamb Marine Naturalist, Cedar Beach [email protected]
16 Steve Lonhart NOAA [email protected]
17 Patrick W. Malecha NOAA [email protected]
18 Peter Mieras Diver [email protected]
19 Roy Mulder Marine Life Sanctuary Society of BC [email protected]
20 Dr. James Murray California State University [email protected]
21 Melva Nikki Van Schyndel Echo Bay EcoVentures [email protected]
22 Bill Proctor (Referred by Salmon Coast Station) [email protected]
23 Dr. Ron Shimek Reef Stewardship Foundation [email protected]
24 Annette G. E. Smith Underwater Photographer [email protected]
25 Dane Stabel Diver [email protected]
26 Doug Swanston Diver [email protected]
27 Mike Tonnesen Diver [email protected]
28 Dr. VerenaTunnicliffe University of Victoria [email protected]
29 Dr. Gary Williams California Academy of Sciences [email protected]
30 Dr. Dennis Willows University of Washington [email protected]
31 Dr. Russell Wyeth St. Francis Xavier University [email protected]
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 6 - November 2014
Table 2 Associated Species Commonly Observed with Orange Sea Pens
Associated Species
Participants
Ru
ssell
Wyeth
Jam
es M
urr
ay
Gary
Wil
liam
s
Den
nis
Wil
low
s
Ro
n S
him
ek
Gre
g J
en
sen
Jim
Co
sg
rove
Do
ug
Sw
an
sto
n
Jac
kie
Hil
deri
ng
Pete
r M
iera
s
An
nett
e S
mit
h
Ch
arl
es B
irkela
nd
Mic
hael
Kyte
Barb
Fag
gett
er
Vere
naT
un
nic
liff
e
Pat
Male
ch
a
Ste
ve L
on
hart
Ch
ris H
arv
ey
Cla
rke
Nudibranchs
Tritonia diomedea X X X X X X X X X X X
Tritonia festiva
X X X X X X X X
X
Armina californica X X
X X X X X X X
X X
Hermissenda crassicornis
X
Flabellina trophina
X
Flabellina verrucosa
X
Sea Stars
Pynopodia helianthoides
X
X
X
Mediaster sp. X X
X X
X
Dermasterias imbricata
X
X
Crossaster papposus
X X
X
Luidia foliolata
X
Solaster sp. X
X
X
Pisaster brevispinus X
Hippasteria sp.
X
X
X X
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 7 - November 2014
Associated Species
Participants
Ru
ssell
Wyeth
Jam
es M
urr
ay
Gary
Wil
liam
s
Den
nis
Wil
low
s
Ro
n S
him
ek
Gre
g J
en
sen
Jim
Co
sg
rove
Do
ug
Sw
an
sto
n
Jac
kie
Hil
deri
ng
Pete
r M
iera
s
An
nett
e S
mit
h
Ch
arl
es B
irkela
nd
Mic
hael
Kyte
Barb
Fag
gett
er
Vere
naT
un
nic
liff
e
Pat
Male
ch
a
Ste
ve L
on
hart
Ch
ris H
arv
ey
Cla
rke
Crabs
Metacarcinus magister
X
X X
X
X X
X X X
Cancer productus
X
X
Metacarcinus gracilis X
X
Pugettia productus
X
Paralithodes camtschaticus
X
Pagurus armatus
X
Rockfish
Sebastes caurinus
X
X
X
X X
Sebastes maliger
X
X X
Sebastes nebulosus
X
Flatfish
Parophrys vetulus
X
X
Pleuronichthys coenosus
X
X
Microstomus pacificus
X
Platichthys stellatus
X
X
X
Citharichthys sordidus
X
Bivalves
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 8 - November 2014
Associated Species
Participants
Ru
ssell
Wyeth
Jam
es M
urr
ay
Gary
Wil
liam
s
Den
nis
Wil
low
s
Ro
n S
him
ek
Gre
g J
en
sen
Jim
Co
sg
rove
Do
ug
Sw
an
sto
n
Jac
kie
Hil
deri
ng
Pete
r M
iera
s
An
nett
e S
mit
h
Ch
arl
es B
irkela
nd
Mic
hael
Kyte
Barb
Fag
gett
er
Vere
naT
un
nic
liff
e
Pat
Male
ch
a
Ste
ve L
on
hart
Ch
ris H
arv
ey
Cla
rke
Panopea generosa X
X
X X
X
Chlamys sp.
X
X
Tresus sp. X
X
Other
Cucumaria miniata
X
Parastichopus californicus
X
Cymatogaster aggregata
X
Rossia pacifica
X
Lunatia lewisii
X X
Squalus suckleyi
X
Virgularia sp. X
Hexagrammos decagrammus
X
Hydrolagus colliei X
Pandalus platyceros
X
Crangon sp.
X
Nassarius sp.
X
Pachycerianthus sp.
X
Table 3 Orange Sea Pen (Ptilosarcus gurneyi) Local Ecological Knowledge
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 9 - November 2014
Distribution Information
Recipient answers to Survey. Information consolidated from all sections of the survey plus emails. Responses are recorded verbatim.
Specific locations of P. gurneyi.
This species is fairly common in most areas of nearshore sand/mud substrate from low intertidal to deep waters. In waters around Vancouver it is a common sand bottom species found in Howe sound and West Vancouver and in Indian Arm at such sites as Whytecliffe Park, Porteau Cove, Bowyer Island , and tends to favour areas with some current. Frequently found in alrge patch aggregations but also singly or in small groups. The striped nudibranch is a common species that parasitizes this species but I have not seen this species commonly in the Vancouver area, more so on the West coast of Vancouver island.
Dr. Chris Harvey-Clarke, UBC
Observations of concentrated aggregations in the regions of Prince Rupert Harbour, Chatham Sound, Browning Entrance, Principe Channel, and Douglas Channel. Sporadic observations in many locations ranging from Dundas Island on the North Coast to Klemtu on the Central Coast. One large bed is located in the Skeena River plume.
Dr. Barb Faggetter, 'Ocean Ecology'
Puget Sound, WA
Dr. Chris Harley, UBC Associate Prof
Puget Sound – From Whidby Is. South to Olympia,
The American San Juan Islands – Waldron, Lopez, San Juan and Orcas.
Vancouver Island – Saanich Inlet, Barkley Sound
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
East end of Strait of Juan de Fuca/Whidbey & Fidalgo Islands.
I regularly observe them in Rosario Bay (only one small stream enters Rosario Bay and they are found about 100m from the stream), which is an exposed location quite near Deception Pass.
Dr. David Cowles, Walla Walla Uni Prof
The highest concentration I have ever seen was off of Mayne Island in a moderate current/soft bottom (lots of shells) area. This area had the highest density of them I have ever seen. North Vancouver Island area also seems to have a fairly high abundance. Passage Island reef (West Vancouver) seems to be a good area to find them. I may not be a biologist, but can provide some location data.
Roy Mulder
Central Puget Sound from Mukilteo to Tacoma including Blake Island, WA
South Puget Sound in the Nisqually Reach and around the western shore of Ketron Island, WA have dense aggregations
The only other location that may have dense aggregations is Dash Point near Tacoma, Washington (location is near the entrance to South Puget Sound).
North Puget Sound in the Cherry Point area
Roberts Bank, B.C. (through materials and information provided by Archipelago Marine Research, Ltd. in 2008)
Michael Kyte, Senior Marine Biologist
Washington State from Puget Sound, north to San Juan County, British Columbia from US boundary northwest outer coast to Cape Scott on Vancouver Island. Specifically, near McIntosh Rocks 5 km NW of Tofino.
Dr. Dennis Willows, Uni of Washington Prof
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 10 - November 2014
Specific locations of P. gurneyi.
Gulf of Alaska, Puget Sound, Oregon to southern California.
Dr. Gary Williams, PhD, Curator Invert Zoology
Puget Sound, San Juan Islands, Barkley Sound, Clayoquot Sound I have a number of tables and maps indicating both possible and known sites in the San Juan Islands and Puget Sound.
Dr. Russell Wyeth, St FX asst. Prof
My experience is mostly in the southern Vancouver Island area from Nanaimo to Sooke. There are several very large fields in the waters surrounding Sidney and James Islands near Sidney. I have some specific area experience in Barkley Sound (west Vancouver Island) and the Port Hardy area (north Vancouver Island).
Jim Cosgrove, Royal BC Museum
2 dense aggregation around inside waters of Southeast Alaska near Juneau.
Pat Malecha, NOAA Marine Ecology & Stock Assess
Along Douglas Island between the city and Marmion Island…..about 6 miles long, large sea pen forests through this areaPoint Louisa Cove side large sea pen forestSunshine Cove – both sides of underwater reef – medium sized sea pen forests. There are sea pen forests in areas around Coughlin Island, but I have not spent enough time underwater there to really discuss that area much.
Annette Smith, Underwater Photographer
I have dived a few times in sea pen beds off Burien WA, Bellingham WA, Lopez Sound WA, Shine, WA, and Tofino B.C.
Dr. James Murray, California State Uni
Gulf Islands, Winchelsea islands, Johnstone Strait, Queen Charlotte Strait, Smith inlet, Kyuquot Sd, Barkley Sd, Nootka Sd, North coast channels (Hakai, Nalau, Seaforth, Millbank, Caamano, Principe, Otter, Beaver, Freeman) Haida Gwaii ( skidegate chan, Cumshewa Chan, Laskeek bay, Hoya Pass, Reef Island, Juan Perez Sd, Skincuttle Inl, Dolomite narrows, Houston Stewart Channel, Anthony Island.
John deBoeck, Director of Dive Industry Asstn of BC
I am familiar with their distribution within Monterey Bay (Monterey Bay Peninsula) and the northern Big Sur coast. **INCLUDED A MAP AND EXCEL FILE REPRESENTING LOCATIONS.
Chad King, NOAA
Plumper Island Group outside of Telegraph Cove, Hoya Head (Knight’s Inlet), Port Alice , “Seven Tree” near Browning Pass, Greenway Sound
Jackie Hildering, Diver
Areas of Saanich at 30 to 50m are dominated by whip corals and sea pens in appropriate sediments. Densities are not measured but we have the imagery that can support measurements.
Dr. Verena Tunnicliffe, UVic Prof
I have seen P. gurneyi in central California in the last couple of years, usually at a site near the entrance to Monterey Harbor. I possibly saw this species during dives on Santa Catalina Island, but it may have been at another site in southern CA.
I’d have to consult my notes if you really needed the info.
Steve Lonhart, NOAA
In Puget Sound near Seattle, mostly at Alki Point and Golden Gardens parks in Seattle.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
West Coast Vancover Island (Bamfield)
Dr. David Arsenault, BMSC
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 11 - November 2014
Specific locations of P. gurneyi.
Barkley Sound
Peter Mieras, Diver
The islands and inlets around the Broughton Archipelago, off the NE tip of Vancouver Island. Echo Bay.
Melva Nikki van Schyndel, Naturalist in Echo Bay
Broughton Archipelago, especially Penphrase Pass with the highest density aggregation
Bill Procter, Broughton Archipelago
Barkley Sound, Broughton Archipelago, Salish Sea, Howe Sound.
Dane Stabel, Diver
Do see the sea pens up east side of Vancouver Island off Qualicum, and out around Hornby Island and inside Denman isl.
Mike Tonnesen, Diver
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 12 - November 2014
Table 4 Orange Sea Pen (Ptilosarcus gurneyi) Local Ecological Knowledge
Recipient answers to Survey. Responses are recorded verbatim.
2 Please describe the area along the Pacific Northwest coast in which you are familiar with P. gurneyi.
This species is fairly common in most areas of nearshore sand/mud substrate from low intertidal to deep waters. In waters around Vancouver it is a common sand bottom species found in Howe sound and West Vancouver and in Indian Arm at such sites as Whytecliffe Park, Porteau Cove, Bowyer Island , and tends to favour areas with some current. Frequently found in alrge patch aggregations but also singly or in small groups. The striped nudibranch is a common species that parasitizes this species but I have not seen this species commonly in the Vancouver area, more so on the West coast of Vancouver island.
Dr. Chris Harvey-Clarke, UBC
Observations of concentrated aggregations in the regions of Prince Rupert Harbour, Chatham Sound, Browning Entrance, Principe Channel, and Douglas Channel. Sporadic observations in many locations ranging from Dundas Island on the North Coast to Klemtu on the Central Coast.
Dr. Barb Faggetter, 'Ocean Ecology'
Puget Sound, WA
Dr. Chris Harley, UBC Associate Prof
East end of Strait of Juan de Fuca/Whidbey & Fidalgo Islands
Dr. David Cowles, Walla Walla Uni Prof
• Central Puget Sound from Mukilteo to Tacoma including Blake Island, WA • South Puget Sound in the Nisqually Reach and around Ketron Island, WA • North Puget Sound in the Cherry Point area • Roberts Bank, B.C. (through materials and information provided by Archipelago Marine Research, Ltd. in 2008)
Michael Kyte, Senior Marine Biologist
Washington State from Puget Sound, north to San Juan County, British Columbia from US boundary northwest outer coast to Cape Scott on Vancouver Island
Dr. Dennis Willows, Uni of Washington Prof
Gulf of Alaska, Puget Sound, Oregon to southern California.
Dr. Gary Williams, PhD, Curator Invert Zoology
Puget Sound, San Juan Islands, Barkley Sound, Clayoquot Sound
Dr. Russell Wyeth, St FX asst. Prof
My experience is mostly in the southern Vancouver Island area from Nanaimo to Sooke. I have some specific area experience in Barkley Sound (west Vancouver Island) and the Port Hardy area (north Vancouver Island).
Jim Cosgrove, Royal BC Museum
Inside waters of Southeast Alaska near Juneau.
Pat Malecha, NOAA Marine Ecology & Stock Assess
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 13 - November 2014
Along Douglas Island between the city and Marmion Island…..about 6 miles long, large sea pen forests through this area
Point Louisa Cove side large sea pen forest
Sunshine Cove – both sides of underwater reef – medium sized sea pen forests.
There are sea pen forests in areas around Coughlin Island, but I have not spent enough time underwater there to really discuss that area much.
Annette Smith, Underwater Photographer
I have 20 years of experience with a sea pen bed near Tacoma WA, and have also dived a few times in sea pen beds off Burien WA, Bellingham WA, Lopez Sound WA, Shine, WA, and Tofino B.C.
Dr. James Murray, California State Uni
Gulf Islands, Winchelsea islands, Johnstone Strait, Queen Charlotte Strait, Smith inlet, Kyuquot Sd, Barkley Sd, Nootka Sd, North coast channels (Hakai, Nalau, Seaforth, Millbank, Caamano, Principe, Otter, Beaver, Freeman) Haida Gwaii ( skidegate chan, Cumshewa Chan, Laskeek bay, Hoya Pass, Reef Island, Juan Perez Sd, Skincuttle Inl, Dolomite narrows, Houston Stewart Channel, Anthony Island.
John deBoeck, Director of Dive Industry Asstn of BC
I am not familiar with its distribution along the Pacific Northwest, but am familiar with their distribution within Monterey Bay and the northern Big Sur coast.
Chad King, NOAA
Plumper Island Group outside of Telegraph Cove, Hoya Head (Knight’s Inlet), Port Alice , “Seven Tree” near Browning Pass, Greenway Sound
Jackie Hildering, Diver
Saanich Inlet
Dr. Verena Tunnicliffe, UVic Prof
I have seen P. gurneyi in central California in the last couple of years, usually at a site near the entrance to Monterey Harbor. As I recall, I first learned about this species while studying in southern CA, and possibly saw it during dives on Santa Catalina Island, but it may have been at another site in southern CA. I’d have to consult my notes if you really needed the info.
Steve Lonhart, NOAA
In Puget Sound near Seattle, mostly at Alki Point and Golden Gardens parks.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
West Coast Vancover Island (Bamfield)
Dr. David Arsenault, BMSC
As a diver regularly working as a diving marine biologist in British Columbia since 1981 between Southern British Columbia, Bowie Seamount 150 Km West of Haida Gwaii and Prince Rupert.
Doug Swanston, Diver Seacology
Barkley Sound
Peter Mieras, Diver
I dive extensively Sidney to Victoria Harbour, Nanaimo north to Cape Lazo, Shearwater Spillar Inlet north including Kitisoo Bay, Queen Charlottes, mainly greater Langara Island
Mike Tonnesen, Diver
The islands and inlets around the Broughton Archipelago, off the NE tip of Vancouver Island.
Melva Nikki van Schyndel, Naturalist in Echo Bay
Broughton Archipelago, especially Penphrase Pass with the highest density aggregation
Bill Procter, Broughton Archipelago
Barkley Sound, Broughton Archipelago, Salish Sea, Howe Sound.
Dane Stabel, Diver
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 14 - November 2014
The highest concentration I have ever seen was off of Mayne Island in a moderate current/soft bottom (lots of shells) area. This area had the highest density of them I have ever seen. North Vancouver Island area also seems to have a fairly high abundance. Passage Island reef (West Vancouver) seems to be a good area to find them. I may not be a biologist, but can provide some location data.
Roy Mulder
Puget Sound – From Whidby Is. South to Olympia, The American San Juan Islands – Waldron, Lopez, San Juan and Orcas. Vancouver Island – Saanich Inlet, Barkley Sound
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Puget Sound / Salish Sea
Dr. Greg Jensen, Uni of Washington
3 Please explain how you are familiar with P. gurneyi and the methods by which you have gathered information on them (e.g., direct dive surveys, studies of sea pens in lab setting, bycatch of sea pens in trawl gear, etc.).
Dive surveys
Dr. Chris Harvey-Clarke, UBC
As an oceanographer and professional biologist, I am familiar with P. gurneyi from both an academic perspective and from field research in which I was carrying out marine benthic surveys. I have gathered information on them primarily through the use of a georeferenced towed benthic video camera system which I have used to identify and enumerate benthic organisms and classify benthic substrates.
Dr. Barb Faggetter, 'Ocean Ecology'
Invertebrate Zoology labs, talks by other researchers
Dr. Chris Harley, UBC Associate Prof
Professor of biology at Walla Walla University’s Rosario Beach Marine Lab near Anacortes, WA. Observed mainly by diving + lab studies.
Dr. David Cowles, Walla Walla Uni Prof
In the Puget Sound , I have had direct experience by conducting diving surveys. In some cases, these surveys were for geoduck clams and in other cases for P. gurneyi. The surveys and observations have extended intermittently from 1966 through 2011.
Michael Kyte, Senior Marine Biologist
Dive observations incidental to other work involving the seaslug predators of seapens, and otter trawl sampling and collecting in WA state.
Dr. Dennis Willows, Uni of Washington Prof
I am a specialist in pennatulacean systematics; geographical data is from our collections database at the California Academy of Sciences, Department of Invertebrate Zoology and Geology.
Dr. Gary Williams, PhD, Curator Invert Zoology
200? SCUBA dives, ~500 hours of timelapse underwater video.
Dr. Russell Wyeth, St FX asst. Prof
I am a retired marine biologist with 20 years of professional employment at the Royal British Columbia Museum. All my research was done by scuba diving however I also participated in studies that involved a variety of fishing and dredging techniques.
Jim Cosgrove, Royal BC Museum
I have observed P. gurneyi while conducting scientific and sport dives.
Pat Malecha, NOAA Marine Ecology & Stock Assess
Many years of diving. Collected Sea Pens for UC Davis (Dr. Dan Nurco)
Annette Smith, Underwater Photographer
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 15 - November 2014
I have explored the sea pen beds describe above as a means to collecting their predator Tritonia diomedea and related sea slugs, and have hand harvested as food for sea slugs I have collected. I have also spent much time observing them in the lab, and do note them as bycatch in several trawls. I have done some chemical and microscopic analysis of their tissues as well
Dr. James Murray, California State Uni
Direct diving- I ran a commercial dive live-aboard for recreational diver & photographers for over 20 years
John deBoeck, Director of Dive Industry Asstn of BC
I have observed them directly while SCUBA diving around Monterey Peninsula. I have also queried the MBARI VARS database for their ROV observations and CSUMB’s media records, which were either observed via ROV or towed camera sled. I have included the map and both excel files representing the observations.
Chad King, NOAA
Photo-documenting as a recreational diver.
Jackie Hildering, Diver
Surveys of benthos by ROV
Dr. Verena Tunnicliffe, UVic Prof
I learned about the species as an undergraduate student at UCLA while taking field courses on Santa Catalina Island. I have also encountered the species while diving for my master’s thesis and doctoral dissertation research, which focused on species within kelp forests, but I was often in sandy areas adjacent to kelp beds and saw the sea pen then.
Steve Lonhart, NOAA
Direct dive observations on their behavior and interactions with their predators.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Study of sea pen in laboratory setting
Dr. David Arsenault, BMSC
Direct Dive Surveys
Doug Swanston, Diver Seacology
Observed while diving and filming
Peter Mieras, Diver
Dive surveys for DFO and harvesting as a seafood harvester, commercial diver, as well as installations of docks.
Mike Tonnesen, Diver
Personal study from books, scientific papers and articles from the Internet; bycatch from prawn fishing; diving
Melva Nikki van Schyndel, Naturalist in Echo Bay
Visual sightings and observations at low tide, including counts of individuals
Bill Procter, Broughton Archipelago
I encounter P. Gurneyi frequently while recreational and professional SCUBA diving, although I have not directly surveyed or studied them.
Dane Stabel, Diver
Direct diver surveys from 1973 through 1994. Laboratory studies of reproduction and embryology.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Dive surveys for other species (diving area since 1974)
Dr. Greg Jensen, Uni of Washington
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 16 - November 2014
4 Have you observed P. gurneyi directly??
Yes, in aggregations of both <4 and > 4 individuals per m2
Dr. Chris Harvey-Clarke, UBC
Yes, in aggregations of both <4 and > 4 individuals per m2
Dr. Barb Faggetter, 'Ocean Ecology'
No
Dr. Chris Harley, UBC Associate Prof
Yes, in aggregations of <4 individuals per m2
Dr. David Cowles, Walla Walla Uni Prof
Yes, in aggregations of both <4 and > 4 individuals per m2
Michael Kyte, Senior Marine Biologist
Yes, in aggregations of <4 individuals per m2
Dr. Dennis Willows, Uni of Washington Prof
Yes, in aggregations of <4 individuals per m2
Dr. Gary Williams, PhD, Curator Invert Zoology
Yes, in aggregations of both <4 and > 4 individuals per m2
Dr. Russell Wyeth, St FX asst. Prof
Yes, in aggregations of both <4 and > 4 individuals per m2
Jim Cosgrove, Royal BC Museum
Yes, in aggregations of both <4 and > 4 individuals per m2
Pat Malecha, NOAA Marine Ecology & Stock Assess
Yes, in aggregations of both <4 and > 4 individuals per m2
Annette Smith, Underwater Photographer
Yes, in aggregations of both <4 and > 4 individuals per m2
Dr. James Murray, California State Uni
Yes, usually less than 4 per m2 Can not recall much more than 4 per m2
John deBoeck, Director of Dive Industry Asstn of BC
Yes, in aggregations of <4 individuals per m2
Chad King, NOAA
Yes, in aggregations of both <4 and > 4 individuals per m2
Jackie Hildering, Diver
Yes, in aggregations of both <4 and rarely > 4 individuals per m2
Dr. Verena Tunnicliffe, UVic Prof
Yes, in aggregations of <4 individuals per m2
Steve Lonhart, NOAA
Yes, in aggregations of both <4 and > 4 individuals per m2
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 17 - November 2014
No
Dr. David Arsenault, BMSC
Yes, in aggregations of both <4 and > 4 individuals per m2
Doug Swanston, Diver Seacology
Yes, in aggregations of both <4 and rarely > 4 individuals per m2
Peter Mieras, Diver
Yes, in aggregations of both <4 and > 4 individuals per m2
Mike Tonnesen, Diver
Yes, in aggregations of <4 individuals per m2
Melva Nikki van Schyndel, Naturalist in Echo Bay
Yes, in aggregations of <4 individuals per m2
Bill Procter, Broughton Archipelago
Yes, in aggregations of <4 individuals per m2, Although I have not directly observed high densities, I have boat tended for a researcher collecting Tritonia nudibranchs in Clayoquot Sound who reported high densities following the dives. (See contact in section 18)
Dane Stabel, Diver
Yes, in aggregations of both <4 and > 4 individuals per m2
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Yes, in aggregations of both <4 and > 4 individuals per m2
Dr. Greg Jensen, Uni of Washington
5 If you observed a dense aggregation of P. gurneyi (i.e. > 4 individuals per m
2), would you consider this to be a unique habitat feature of the
area? Please explain why and describe the density of the P. gurneyi aggregation that you observed (#’s per m2).
Finding densities this high is not typical however I would estimate 20 percent of the observations I have made would be of this high a density, usually in current swept areas.
Dr. Chris Harvey-Clarke, UBC
Unfortunately, since P. gurneyi has never been a "species of interest" during any of our surveys, I do not have accurate density estimates for them. Typically, in a dense bed, I would observe 2 to 3 individuals per video frame. Since each video frame is approximately 0.2 m
2, this would work out to be approximately 10 to 15 individuals per
m2. Where P. gurneyi occurs at these densities, I definitely consider this to be a unique habitat feature of the area.
In general, while I have observed P. gurneyi at low densities (e.g., much less than 1 individual per m2) commonly
throughout much of the North and Central Coast, I have only observed very dense aggregations at a small number of sites. Therefore, while no specific conservation issues have yet been flagged for P. gurneyi, I do comment on the presence of dense aggregations when I submit reports to clients based on the results of our benthic surveys.
Dr. Barb Faggetter, 'Ocean Ecology'
Yes, that seems like quite a dense aggregation. I typically find them at not more than 1-2/m2 though some can be hiding below the sand.
Dr. David Cowles, Walla Walla Uni Prof
I have observed “dense aggregations” of P. gurneyi where the measured population density was 10 to 30 individuals/m². These occurred along the eastern side of Puget Sound between Edmonds and Tacoma and in South Puget Sound on the western shore of Ketron Island. I would not consider that these relative dense populations were a “unique feature” because this “feature” occurred at a number of locations under a variety of biotic and abiotic conditions. In addition, similar habitats (i.e., silty sand) with few or none P. gurneyi have been found. The most recent (2011) relatively dense aggregation that I have observed was during geoduck stock assessment surveys in South Puget Sound. A notably dense aggregation was found along the western shore of Ketron Island. This population closely resembled the aggregations described by Birkeland (1974).
Michael Kyte, Senior Marine Biologist
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 18 - November 2014
I do not fully understand the question. Dense sea pen beds are patchily distributed, associated with a very particular set of flow and substrate features. So depending on how you define ‘area’ they may be unique (i.e. the only patch) or not. I have observed up to at least 20 per m
2, probably higher.
Dr. Russell Wyeth, St FX asst. Prof
Yes, there are several very large fields of P. gurneyi in the waters surrounding Sidney and James Islands near Sidney, B.C. These areas are mostly flat sand with moderate to strong currents. This area is commercially fished for Cancer productus crab. I would estimate the density to vary from 4 per m
2 to 8 per m
2.
Jim Cosgrove, Royal BC Museum
I know of 2 aggregations of P. gurneyi near Juneau where density of the colonies are greater than or equal to 4 individuals per m
2. In these areas, P. gurneyi is a dominant feature on the seafloor which could be considered
unique,
Pat Malecha, NOAA Marine Ecology & Stock Assess
Where we have orange sea pens, they are fairly thick. We call them sea pen forests, as that is what they look like. However, viewing them depends on tides and currents, as they pull down into the ground when there isn’t much current running. The areas where orange sea pens reside, they are pretty much the only growing “plant type” sea life there. White sea pens (aka sea whips) occupy areas deeper. So, normally, you will see a sea pen forest, pass through it, then a little deeper, the sea whips will start.
I have lots of slides and photos of these areas.
Annette Smith, Underwater Photographer
I have observed dense and sparse aggregations. The dense ones have had up to 10 per m2. In ideal habitat (flat, sandy,muddy bottom with adequate plankton to feed on), these densities are common, and the beds can persist for decades. A sea pen bed is a “unique habitat” and supports the presence of many other associated species such as sea slug predators, specific hermit crabs, flatfish, and crabs. When densities of sea pens are low, they do not have as an important effect on other species.
Dr. James Murray, California State Uni
I have not observed a dense aggregation.
Chad King, NOAA
In my experience as a diver, these dense aggregations certainly appear to be rare and are associated with species like Triotonia festiva. They appear to have very specific habitat needs – low flow, a substrate high in sand and shell debris. The little clip I have made up at the following link gives a sense of this. http://themarinedetective.com/tag/diamondback-nudibranch/
Jackie Hildering, Diver
“unique”? - not understanding the term. Areas of Saanich at 30 to 50m are dominated by whip corals and sea pens in appropriate sediments. Densities are not measured but we have the imagery that can support measurements.
Dr. Verena Tunnicliffe, UVic Prof
I have not seen dense clusters of P. gurneyi, but I would consider such an aggregation to be rare for the habitats I have experience in, which includes the shallow subtidal (<30 m) in southern and central CA.
Steve Lonhart, NOAA
I do not understand what is meant by “unique habitat feature”. I did not estimate #’s per m2 because I had no way of knowing how many or what proportion of the population was withdrawn into the sand and out of sight.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Yes, A unique assemblage of biota are associated with this habitat type. 4 and 20 P. gurneyi/m2
Doug Swanston, Diver Seacology
Approx 6 /m2 these are a few small areas of sandy bottom in medium current velocity .
Peter Mieras, Diver
Yes it would be unusual. Generally the aggregations are less dense and often you only see one on a reef.
Bill Procter, Broughton Archipelago
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 19 - November 2014
I have seen this density commonly in virtually all of the areas I examined. Densities of adults are often quite a bit higher than seems so with a casual survey. The pens move up and down in the sediment burying themselves sometimes several times a day. Consequently, examination of a site by divers tends to underestimate the abundances and densities. Adult abundances in many beds exceeds 10 per m
2; Additionally, after settlement of
the planktonic juveniles abundances can often be well in excess of 250 per m2
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
yes, because it influences overall species diversity- many seastars and nudibranchs that wouldn't be there if it was only a bare sand bottom.I don't have the data at hand for the surveys that measured density
Dr. Greg Jensen, Uni of Washington
6 Did you observe juvenile fish or invertebrate species (e.g., rockfish, geoducks, shrimp, crabs) associated with P. gurneyi? Identified species can be associated with both small (<4 / m
2) and large (>4 / m
2) P. gurneyi aggregations. Please provide a description of associated species.
Yes, i. Bivalve species especially geoduck, horse and other large bivalves and ii. sea whips where beds are found in deeper water (25 m and deeper) are another common co aggregating species
Dr. Chris Harvey-Clarke, UBC
Yes
i. Copper rockfish (Sebastes caurinus) - adults ii. China rockfish (Sebastes nebulosus) - adults iii. Quillback rockfish (Sebastes maliger) - adults iv. Geoduck clam (Panopea abrupta) v. Scallop (Chlamys spp.) vi. Dungeness crab (Cancer magister) vii. Red sea cucumber (Cucumaria miniata) viii. California sea cucumber (Parastichopus californicus)
Dr. Barb Faggetter, 'Ocean Ecology'
No
Dr. David Cowles, Walla Walla Uni Prof
Yes • Juvenile Copper or Quillback rockfish vertically oriented to an individual P. gurneyi • Geoduck and gaper (Tresus sp.) are often associated with P. gurneyi beds. • Cancroid crabs (Cancer sp. and Metacrinus sp.) • The seastars Luidia foliata and Pycnopodia helianthoides • A variety of adult and juvenile flatfish including C-O Sole, Starry Flounder, and others • A variety of predators on P. gurneyi – see Question 8
Michael Kyte, Senior Marine Biologist
Yes i. C.magister, ii. C.productus, iii. starry flounder, iv. English v. COsole, vi. seaslugs(Tritoniaand Armina)
Dr. Dennis Willows, Uni of Washington Prof
Yes, Nudibranchs in the genus Tritonia.
Dr. Gary Williams, PhD, Curator Invert Zoology
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 20 - November 2014
There are numerous associated species that I have observed. However, are you only interested in juveniles? Are you are trying to assess whether they are a nursery habitat? Proper identification of juvenile versus adults for the associated species is not something I have done. I expect many do not spend their entire lives in sea pen beds, but I do not have adequate information to delineate whether they are present as adult, juvenile or both. There are more than what I list below, however I would like clearer delineation of your criteria for including species in the list before I continue.: i. Tritonia diomedea ii. Armina californica iii. Virgularia sp. (in mixed pen and whip beds) iv. Pycnopodia helianthoides v. Solaster sp. vi. Mediaster sp. vii. Pisaster brevispinus viii. Zostera (in shallow areas) ix. Horse clams x. Geoduck xi. Ratfish xii. Sole xiii. Hermit crabs xiv. Cancer gracilis
Dr. Russell Wyeth, St FX asst. Prof
Yes i. A few rockfish (mostly S. carinus)_but more Kelp Greenlings ii. Cancer magister crab_and a variety of smaller shrimp species iii. Several very rare nudibranch species including Tritomia festiva, Tritonia diomedia and Armina californica
Jim Cosgrove, Royal BC Museum
Yes , Winter red king crab associations
Pat Malecha, NOAA Marine Ecology & Stock Assess
Yes, Dungeness Crab - Decorator crab really like being inside the sea pens and they even will decorate their shells with sea pens- hermit crabs, etc. One crab I almost never see among the sea pens is king crab. Not sure why, as they move through the areas….just normally they move deeper than the orange sea pens are, then come up shallow.Wide variety of nudibranchs – in Sunshine Cove some of the largest tochuinas recorded have been found in there. The large nudibranchs generally do not mix. So….areas where diomedias reside with sea pens, you generally don’t see tochuinas (and vice versa)iii. Clams, scallops, mussels, etc.iv. I don’t see rockfish in their areas much, as the juvenile rockfish tend to be in the wallsv. _Sculpins, snailfish, gunnels, etc
Annette Smith, Underwater Photographer
Yes i. flatfish like starry flounder ii. hermit crabs iii. sea slugs Armina californica, Tritonia festiva, and Tritonia diomedea iv. sea stars like Mediaster, Hipposterias v. Cancer magister
Dr. James Murray, California State Uni
I cannot recall specific species associations.
Chad King, NOAA
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 21 - November 2014
Yes i. Juvenile kelp crabs ii. Potentially juvenile copper rockfish iii. Sea slug predators mention in question 8
Jackie Hildering, Diver
Yes?? “Associated” really should be a statistical test. my observations are idiosyncratic i. spot prawns ii. English and dover sole iii. dungeness crab
Dr. Verena Tunnicliffe, UVic Prof
Yes, as I recall, YOY rockfishes were in the vicinity, as well as sanddabs and possibly some scavenging snails, like Nassarius
Steve Lonhart, NOAA
Yes There were some commensal associates such as tiny shrimp. I can send a closeup photo of one of the commensal shrimp if you wish.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
o Yes .i. Tritonia diomedea .ii. Tritonia festiva .iii. Armina californica
Doug Swanston, Diver Seacology
YES .i. Striped and orange peel nudibranchs .ii. Dungeness and red rock crabs .iii. Juv rock fish .iv. General sand bottom animals
Peter Mieras, Diver
o Yes i. sea stars, cukes, nudibranchs and other sandy bottom dwellers
Mike Tonnesen, Diver
No
Melva Nikki van Schyndel, Naturalist in Echo Bay
No
Bill Procter, Broughton Archipelago
Yes i. There is an array of predators commonly found with P. gurneyi, (4-5 species of sea stars, and a like number of nudibranchs. See this link for more details: http://ronshimek.com/blog/?cat=218 ii. Additionally: geoducks present in beds where the density of adults is lower; they appear absent in dense beds.._Pachycerianthus common. iii. Cancer gracilis and C. magister both are found in the beds, but not commonly. Crangon spp. shrimps, very common. Rossia pacifica present. Copper Rockfish, Quillback Rock fish present.; Squalus present, sometimes abundant.; Euspira lewisii, common. iv. Shiner perch common (Puget Sound areas).
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
I haven't noticed any special associations with fish in our area. Geoducks often occur in the beds, but not at densities any higher than on open sand bottoms in the same general area; same goes for Pycnopodia, moon snails, and Pagurus armatus. Sea pen predators (and their predators) are much higher, so Hippasterias, Tritonia, Mediaster, and Armina are usually abundant, and Crossaster is more common too.
Dr. Greg Jensen, Uni of Washington
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 22 - November 2014
7 Do you believe the above mentioned species associations to be coincidental? (ie. both species simply prefer the same habitat) OR do you believe that these species have important interactions between one-another? (I.e. juvenile fish rely on sea pens as a refuge from predators)? Please explain.
No data to support this but my impression is that the current conditions are what makes these species share habitat
Dr. Chris Harvey-Clarke, UBC
In the case of sessile species (e.g., geoduck clam, red and California sea cucumbers), the species association with P. gurneyi is most likely coincidental, and probably reflects a preference for sandy habitats with moderate currents. In the case of motile species (e.g., rockfish and crab), the species association with P. gurneyi probably represents a beneficial species interaction. In flat, relatively featureless benthic habitats, I have often observed clusters of motile organisms (fish, shrimp, crab, squat lobsters) around a single tube worm, sea whip, or sea pen. Apparently, some organisms, such as prawn, are not usually associated with barren sediments, but appear to actively seek out habitats that are more complex [Schlining, K. L. 1999. The spot prawn (Pandalus platyceros Brandt 1851) resource in Carmel submarine canyon, California: Aspects of fisheries and habitat associations. Moss Landing Marine Laboratories. Stanislaus, California State University. M.Sc.: 54 pp.]. I suspect that there may be several possible explanations for these associations. Scavengers, such as crab and shrimp, may benefit from large particulate "food" which has been caught by a sea pen or tube worm, but rejected due to its large size. Some organisms, such as squat lobsters, may use sea pens, sea whips, or tube worms as "stakes" marking their territories. Small fish may use sea pens as refuges from predation, whereas larger fish may be benefiting from the current microeddies that form around the sea pen (reduces swimming effort or makes prey items easier to catch).
Dr. Barb Faggetter, 'Ocean Ecology'
In the case of the juvenile rockfish associated with vertical expanded P. gurneyi, the individual fish were apparently using the P. gurneyi for shelter or refuge from predators. Juvenile and adult rockfish often seek out vertical objects with which to orient likely for refuge from predators and feeding. Thus, the association of juvenile rockfish with P. gurneyi is probably an opportunistic event.
Geoduck and gaper clams are often found in P. gurneyi beds likely because the sediment, water circulation, and plankton characteristics are amenable to both species. This association is not obligatory because both clams and sea pens are found without the other.
As with the geoduck and gaper clams, cancroid crabs, flatfish, and the seastars L. foliata and P. heliantoides co-occur with P. gurneyi likely because of biotic and abiotic habitat characteristics favorable and preferred by the species. Pycnopodia occasionally preys on P. gurneyi because the seastar is an opportunistic predator.
Michael Kyte, Senior Marine Biologist
Seaslugs eat the seapens. The other species may be coincidental.
Dr. Dennis Willows, Uni of Washington Prof
These nudibranchs feed upon the sea pen Ptilosarcus gurneyi.
Dr. Gary Williams, PhD, Curator Invert Zoology
The seastar-nudibranch-sea pen community is based on a known trophic network. Similarly, I think there are some bivalves and bivalve predators that co-exist. I would cautiously speculate that the geoducks and sea pens do not interact much, and thus the two trophic chains maybe somewhat independent and thus occur coincidentally.
Dr. Russell Wyeth, St FX asst. Prof
For the fish, shrimp and crabs I would say that it is a matter of food being abundant for all groups. There probably is a prey/predator relationship betwenne the fish and small shrimps. The nudibranchs are predators on the sea pens
Jim Cosgrove, Royal BC Museum
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 23 - November 2014
It is likely that the association is coincidental but also likely that the two species prefer similar substrates.
Pat Malecha, NOAA Marine Ecology & Stock Assess
Not so sure of the juvenile fish, However, I do know tochuinas really love to eat the sea pens. Diomedias also eat sea pens. They tend to not occupy the same places as the tochuinas. For example, you almost never see a diomedia in Sunshine Cove. There are lots of diomedias at Point Louisa yet you never see tochuina’s there. Decorator crabs are often found hiding in the sea pens. They also use sea pens as part of their camouflage. Dungeness crab will often hide under the sea pens. Sometimes you will see snail fish hiding under seapens, however, only if there is a shell they can curl up in.
Annette Smith, Underwater Photographer
The slugs depend on the pens as their exclusive food. The stars also seem to specialize on eating the pens nearly exclusively. The hermit crab species I see was cited in a crab book as being specifically associated with sea pen beds. The flatfish and cancer crabs I think are mainly coincidental as they do not eat the pens or require their shelter. There are also specific isopods that are symbionts that live inside sea pens.
Dr. James Murray, California State Uni
Juvenile fish DO rely on sea pens for refuge & shelter
John deBoeck, Director of Dive Industry Asstn of BC
I do not have enough information to answer this.
Chad King, NOAA
Not coincidental for sea slugs – key prey item.
Jackie Hildering, Diver
It is likely that sea pens provide the bottom roughness that some species seek – we have not done the tests necessary.
Dr. Verena Tunnicliffe, UVic Prof
In some cases, the sea pen provides habitat to mobile species, and especially small fishes. I am not sure if this results in net positive production for those species that opportunistically use the sea pen vs. a simple redistribution of the species that are already there.
Steve Lonhart, NOAA
Although Ptilosarcus is preyed upon by at least seven species of predators (four asteroids and 3 nudibranchs), I suspect that only Hippasteria, Armina and Tritonia are associates.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Interspeceis interactions including preditor prey
Doug Swanston, Diver Seacology
The striped and orange peel nudibranchs feed on the orange sea pen
Peter Mieras, Diver
I think coincidental; do not see fish interacting with sea pens
Mike Tonnesen, Diver
Unsure
Bill Procter, Broughton Archipelago
Obviously, the predatory array found with the pens is not coincidental. Probably none of the other associations are incidental either. The bioturbation of the habitat by the pens severely disturbs the substrate, and this seems to elimate most other sediment dwelling species such as clams after a period of time. There are probably other important interactions, but this is the big one.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Geoducks, Pagurus armatus, Pycnopodia and moon snails appear to be coincidental; others mentioned above are either eating the pens or (in the case of Crossaster) eating the nudies.
Dr. Greg Jensen, Uni of Washington
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 24 - November 2014
8 Did you observe predators (i.e. nudibranchs and sea stars) near P. gurneyi colonies? Please describe interaction.
See above comment 2 re striped nudibranch
Dr. Chris Harvey-Clarke, UBC
Yes, I observed predators near P. gurneyi colonies. While most sea star species generally occurred both near P. gurneyi colonies and at locations where there were no P. gurneyi, I definitely observed concentrations of sea stars in and around some of the colonies. Specific species of sea stars which I have seen in high abundance around P. gurneyi colonies are rose stars (Crossaster papposus), painted stars (Orthasterias koehleri), sunflower stars (Pycnopodia helianthoides), long ray stars (Stylasteria forreri), false ochre stars (Evasterias troschelli), ochre stars (Pisaster ochraceus), and short-spined stars (Pisaster brevispinus). I have also observed white-lined nudibranchs (Dirona albolineata) feeding on P. gurneyi. In this situation, the nudibranchs were not found outside the P. gurneyi colony at the study site.
Dr. Barb Faggetter, 'Ocean Ecology'
I have not directly observed predation but am well aware of several local predators and have seen the results of predation (stripped pens)
Dr. David Cowles, Walla Walla Uni Prof
During my work with Charles Birkeland (1968, 1974) and in later years and other locations, I have frequently encountered species that are documented predators of P. gurneyi. On occasion, these species, especially the sea stars, have been observed in the absence of P. gurneyi. Where P. gurneyi were present, the predators were observed feeding on P. gurneyi, foraging between individuals P. gurneyi, and mating or laying egg masses. I have observed nudibranchs, especially Armina, and seastars, particulary Hippasteria and Solaster sp., actively feeding on P. gurneyi.
Michael Kyte, Senior Marine Biologist
Yes, nudibranchs, hunt and eat seapens
Dr. Dennis Willows, Uni of Washington Prof
Yes, see 6 & 7 above
Dr. Gary Williams, PhD, Curator Invert Zoology
Many times. Tritonia grazes on Ptilosarcus, leaving the bulk of the colony unharmed. Packs of Armina consume entire Ptilosarcus. My colleagues and I have observed Hippasterias wipe out an entire sea pen bed, as described by Birkeland.
Dr. Russell Wyeth, St FX asst. Prof
Yes, see above answer regarding nudibranchs. No sea stars that I recorded. I have photos of some of the nudibranchs feeding on P. gurneyi.
Jim Cosgrove, Royal BC Museum
I have observed the nudibranch Tritonia festiva.
Pat Malecha, NOAA Marine Ecology & Stock Assess
See above. Tochuinas and diomedias enjoy dining on sea pens. I see lots of baby basket stars but they generally are not found around the orange sea pens. They tend to use the larger white sea whips for protection. Our orange sea pens are fairly shallow, while the sea whips live deeper.
Annette Smith, Underwater Photographer
Yes, the 3 nudibranchs above eat the sea pens as their exclusive food source. See above for sea stars predation too. One sea pen bed I observed for 20 years was recently eliminated, and this coincided with an increase in Hipposterias predation.
Dr. James Murray, California State Uni
Yes- toquerina tetraquatra eat them
John deBoeck, Director of Dive Industry Asstn of BC
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 25 - November 2014
I do not have enough information to answer this.
Chad King, NOAA
I have photographed Tochuina tetraquetra and Triotonia festiva feeding on orange sea pens. I have observed Armina californica doin 8g so. Painted sea stars, leather star rose star, morning sun star.
Jackie Hildering, Diver
insufficient observations
Dr. Verena Tunnicliffe, UVic Prof
I have seen Dendronotus iris near P. gurneyi.
Steve Lonhart, NOAA
You cited my paper “Birkeland 1974”, and that describes all I can remember.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Yes
Doug Swanston, Diver Seacology
Striped and orange peel nudibranchs feeding on the orange sea pen
Peter Mieras, Diver
I do see sea stars and nudibranchs but do not recall interactions
Mike Tonnesen, Diver
Yes, I saw a sunflower star wrapping itself on it and so I assume it was attempting to eat it in their upright form.
Melva Nikki van Schyndel, Naturalist in Echo Bay
No
Bill Procter, Broughton Archipelago
Of course, again see the link: http://ronshimek.com/blog/?cat=218
Asteroids: Hippasteria spinosa, Crossaster papposus, Dermasterias imbricata, Mediaster aequalis = all observed eating pens.
Nudibranchs: Armina californica, Tritonia festiva, Tritonia diomedea, Tritonia tetraquetra, all observed eating adults. Hermissenda crassicornis, Flabellina trophina, Flabellina verrucosa – commonly in the beds, presumably eating juvenile sea pens.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Many times- Hippasterias and Armina feeding on pens. Have rarely caught Tritonia or Mediaster in the act.
Dr. Greg Jensen, Uni of Washington
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 26 - November 2014
PART B. ABIOTIC FACTORS
9 Were observed P. gurneyi found in sandy substrate? Please explain the observed substrate type.
Yes, shell sand and mud ss
Dr. Chris Harvey-Clarke, UBC
I have observed P. gurneyi in substrates ranging from silt-mud to sand-cobble. Most frequently, large P. gurneyi colonies have occurred in silt-mud to sand substrates.
Dr. Barb Faggetter, 'Ocean Ecology'
Yes, primarily sand
Dr. David Cowles, Walla Walla Uni Prof
P. gurneyi that I have observed have most often been associated with sandy sediments with varying degrees of finer sediments (i.e., silt). I have also observed single P. gurneyi in gravel or rocky habitats where the P. gurneyi occupied a pocket of sandy or silty gravel.
Michael Kyte, Senior Marine Biologist
Sandy and muddy substrates, yes
Dr. Dennis Willows, Uni of Washington Prof
Yes, sandy or other soft bottom sediments.
Dr. Gary Williams, PhD, Curator Invert Zoology
Sea pens seem to prefer shallow shelving sand-mud mixed substrates. Shell content seems to vary in my experience. Steep shelving areas also occasionally (but less frequently) support high density beds. Flat and muddy substrates tend to have more Virgularia (if any pennatulaceans are present at all).
Dr. Russell Wyeth, St FX asst. Prof
Yes, the majority have been found either in sand or in mixed sand/mud substrate.
Jim Cosgrove, Royal BC Museum
The P. gurneyi aggregations are in areas with sandy substrates with little vertical relief.
Pat Malecha, NOAA Marine Ecology & Stock Assess
In most cases our waters have a silty bottom. Sea pens live in the silty areas. They do not live on rock walls, and I have not seen them in the slides on walls.
Annette Smith, Underwater Photographer
Yes, sandy/muddy substrate with a substantial diatom mat.
Dr. James Murray, California State Uni
Sandy and/or sand/shell and/or sand/shell/pebble
John deBoeck, Director of Dive Industry Asstn of BC
I directly observed them in sandy substrate
Chad King, NOAA
Yes –dense aggregations appear to be if there is high shell debris in sand.
Jackie Hildering, Diver
silt to fine sand
Dr. Verena Tunnicliffe, UVic Prof
Yes, usually fairly fine sediment.
Steve Lonhart, NOAA
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 27 - November 2014
Yes. Sandy.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Yes
Doug Swanston, Diver Seacology
Sandy bottom
Peter Mieras, Diver
Sandy bottoms and slightly cobbled, gravel
Mike Tonnesen, Diver
Yes it was fine sandy. At points more muddish in texture
Melva Nikki van Schyndel, Naturalist in Echo Bay
They were observed on a flat, rocky reef with shell pieces, at depth of about 4 feet at low tide.
Bill Procter, Broughton Archipelago
I have seen them in sandy and coarser shell substrates.
Dane Stabel, Diver
I have found them in sand, shell fragment gravel, sandy silt. They don’t like really silty habitats.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Almost always in fairly clean sand (no silt or mud). Occasionally in areas with gravel mixed in.
Dr. Greg Jensen, Uni of Washington
10 Have you found P. gurneyi in high flow environments? Please explain.
defintley – moderate currents for the most part- extreme current environments not so much
Dr. Chris Harvey-Clarke, UBC
Yes, I have found P. gurneyi in high flow environments. As an example, one P. gurneyi colony that we have surveyed was located at the end of a point which had high tide and wave activity. Another P. gurneyi colony was located in a shallow region of Prince Rupert harbour, where the high tidal range generates very strong currents in the shallows.
Dr. Barb Faggetter, 'Ocean Ecology'
Yes, in moderately high flow. I regularly observe them in Rosario Bay, which is an exposed location quite near Deception Pass. Currents in the bay itself don’t often exceed 1 knot but are seldom completely still.
Dr. David Cowles, Walla Walla Uni Prof
I have occasionally found P. gurneyi in relatively high flow conditions. The most recent of these was in South Puget Sound where P. gurneyi was found in relatively coarse well-sorted sand that was heavily rippled by strong tidal currents. In addition, the photographic materials provided to me by Archipelago Marine Research, Ltd. In 2008 clearly showed P. gurneyi in an area subject to strong currents. The relative current strength was evident from the inclined position of the individual P. gurneyi, sand ripples, and the behavior of the scuba divers.
Michael Kyte, Senior Marine Biologist
Yes near McIntosh Rocks 5 km NW of Tofino
Dr. Dennis Willows, Uni of Washington Prof
No
Dr. Gary Williams, PhD, Curator Invert Zoology
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 28 - November 2014
This is hard to answer. Certainly, I have experienced a few sites where flow approach dangerous speeds for SCUBA. However, I have not observed them around Race Rocks, which has very high flow. But then, diving in higher flow environments is more restricted to rocky substrates where the topography provides local refuges for SCUBA divers.
Dr. Russell Wyeth, St FX asst. Prof
The largest colonies are always in areas of moderate to high current. The density drops off the farther you are out of the current stream. Places of low current such as Saanich Inlet have some P. gurneyi but the colonies are very isolated and often number less than 10 individuals.
Jim Cosgrove, Royal BC Museum
No, the areas are affected by tidal exchanges.
Pat Malecha, NOAA Marine Ecology & Stock Assess
Define high flow. Yes, they tend to like areas of current but not rushing like a river. They will generally be hidden when the waters are calm and rise up when there is water movement. Note…I said generally, not usually or always!
Annette Smith, Underwater Photographer
Yes, they require high flow, ranging from 20-100 cm/s.
Dr. James Murray, California State Uni
YES- most higher density colonies are in waters which move at > 1 m/sec max flow- and up to 6 m/sec max flow They seem to ‘thrive’ in waters which move at 1 to 3 m/sec (max flow speed on largest tides)
John deBoeck, Director of Dive Industry Asstn of BC
Not personally
Chad King, NOAA
No
Jackie Hildering, Diver
No
Dr. Verena Tunnicliffe, UVic Prof
I have not noted that, but then I tend to avoid high flow environments while diving.
Steve Lonhart, NOAA
Yes, but also in low-flow environments.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Yes
Doug Swanston, Diver Seacology
Medium velocity areas
Peter Mieras, Diver
do not recall, but work a lot in these areas and it does not stand out
Mike Tonnesen, Diver
Medium flow. But mostly slow/calm flow environments. No rapids but strong currents at times moving through channel gap (+100ft)
Melva Nikki van Schyndel, Naturalist in Echo Bay
No
Bill Procter, Broughton Archipelago
Occasionally, but only in areas where they have been protected from major current flow (i. e. in the lee of large rocks).
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Yes, but I don't have measurements of flow speed. Strong enough that it is difficult to swim against, so probably about a knot. In some of the higher flow places the bottom tends to be more gravelly and I see juveniles but not adults.
Dr. Greg Jensen, Uni of Washington
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 29 - November 2014
11 At what depth range did you observe P. gurneyi?
6m to 45 m
Dr. Chris Harvey-Clarke, UBC
I have observed P. gurneyi at depths ranging from 5 m to 65 m. The most common depth range for P. gurneyi that we have surveyed has been from 10 m to 30 m.
Dr. Barb Faggetter, 'Ocean Ecology'
Approximately 8-10 m
Dr. David Cowles, Walla Walla Uni Prof
I have observed P. gurneyi from the intertidal zone down to over 50 meters MLLW.
Michael Kyte, Senior Marine Biologist
15m to 3m, along shorelines usually, but less often down to 35 . Could reflect my diving depth habits and constraints.
Dr. Dennis Willows, Uni of Washington Prof
Approximately 25 ft. – 225 ft.
Dr. Gary Williams, PhD, Curator Invert Zoology
2m – 30m by SCUBA. I have alse seen a few trawled from deeper, but have not spent much time doing that.
Dr. Russell Wyeth, St FX asst. Prof
Normal scuba diving depths from 1 meter to 30 meters.
Jim Cosgrove, Royal BC Museum
10-30 m
Pat Malecha, NOAA Marine Ecology & Stock Assess
Usually between 30 and 80 feet. Most of them are in the 35 to 60 foot range. I have never seen them at the 100 foot level….but then, I am usually diving walls at that depth and these guys don’t hang out on walls!! I never see sea pens near walls, even in the slide areas of a wall.
Annette Smith, Underwater Photographer
Usually not found shallower than 5 m MLLW, and not often deeper than 30 m.
Dr. James Murray, California State Uni
7 m to 45 m
John deBoeck, Director of Dive Industry Asstn of BC
40-80 feet. Further depth ranges can be found within the attached files.
Chad King, NOAA
From about 15 feet to about 80 feet (limited only by my diving depth I believe – likely deeper). Seem to do particularly well in the shallow – forming “fields”.
Jackie Hildering, Diver
30 to about 60 m but can get better range if necessary
Dr. Verena Tunnicliffe, UVic Prof
From 6-30 m deep.
Steve Lonhart, NOAA
As deep as I could dive, i.e., about 150 ft.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 30 - November 2014
to 30 m RTCD
Doug Swanston, Diver Seacology
From 5meters down to 20 meters
Peter Mieras, Diver
generally 10 to 40 feet
Mike Tonnesen, Diver
approx 30ft and at low tide some areas are approx 10 ft
Melva Nikki van Schyndel, Naturalist in Echo Bay
3-4 feet depth at low tide but they are often much deeper.
Bill Procter, Broughton Archipelago
20-100ft
Dane Stabel, Diver
US datum: -0.3m to -50m; trawled from – 200 m.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Generally from 20-80 ft., but that's the depth for most of my dives.
Dr. Greg Jensen, Uni of Washington
12 Please describe any unique attributes of the surrounding environment where you observed P. gurneyi. Specifically, please comment on any freshwater outflows that may have been present in the vicinity.
Most areas I dive are away from fw sources due to sediment and diminished visibility so this would be hard to determine
Dr. Chris Harvey-Clarke, UBC
The largest aggregations of P. gurneyi that I have observed have been in environments with low slope, low rugosity, and moderate to high currents. Several of the largest aggregations have been associated with some amount of fresh water input - one large bed is located in the Skeena River plume, another is located near a small creek, and a third is close to a waterfall exiting from a freshwater lake.
Dr. Barb Faggetter, 'Ocean Ecology'
Only one small stream enters Rosario Bay. The P. gurneyi are first found about 100 m from the stream. The Skagit River empties into the ocean at the other end of Deception Pass so much freshwater enters the ocean nearby. Salinity near the sea pen colony in the summer is about 29 ppt.
Dr. David Cowles, Walla Walla Uni Prof
I cannot think of any unique attributes of the habitats in which I have found P. gurneyi. All the habitats have been estuarine by definition. In particular, South Puget Sound receives the outflow of a number of streams including the relatively large Nisqually River on whose delta I have seen P. gurneyi. The most characteristic P. gurneyi habitat feature is the silty sand in which they are most commonly found.
Michael Kyte, Senior Marine Biologist
Often there are freshwater outlets nearby.
Dr. Dennis Willows, Uni of Washington Prof
N/A
Dr. Gary Williams, PhD, Curator Invert Zoology
I have spent considerable energy attempting to identify candidate sites for sea pen beds. The factors I came to focus on were: some flow, sand or mud substrate, and shelving substrate (i.e. not flat enclosed bays, nor steep rocky drop-offs). A number of known sea pen beds have nearby fresh water input. However, I do not believe anyone has done the critical comparison to establish that sites without freshwater input but all the other substrate and flow characteristics are less likely to have sea pens.
Dr. Russell Wyeth, St FX asst. Prof
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 31 - November 2014
I am not aware of any freshwater associations with P. gurneyi. My research involved the giant Pacific octopus (Enteroctopus dofleini). Because E. dofleini is a major predator on crabs such as C. productus and C. magister I tended to work in rocky areas that abutted sand or mud flats.
Jim Cosgrove, Royal BC Museum
Freshwater outflows are not found at the sites.
Pat Malecha, NOAA Marine Ecology & Stock Assess
In Southeast Alaska fresh water outflows are everywhere…..they do not seem of affect the sea pens. I don’t see bigger or smaller forests around fresh water. What I find interesting is why tochuina’s and diomedia’s (both feed on sea pens) do not comingle.
Annette Smith, Underwater Photographer
Interesting that you should ask (sounds like a leading question asked by someone who knows!). I am not an ecologist and have not done a careful survey, but it is my impression that sea pen beds are associated with freshwater outflows.
Dr. James Murray, California State Uni
No freshwater outflows present (nearby = closer than 200 m) where highest aggregations observed. Do see them at shelf at outlets of tidal but fresh-water-fed inlets/lagoons/bays
John deBoeck, Director of Dive Industry Asstn of BC
None that I can recall
Chad King, NOAA
No freshwater outflows observed.
Jackie Hildering, Diver
No freshwater; but P.g. does not venture near the hypoxic zones of Saanich.
Dr. Verena Tunnicliffe, UVic Prof
I was not aware of fresh water or any other unusual abiotic features. They are usually in sandy areas which tend to be relatively featureless except for some species, such as the pen itself, which sticks up above the flat plain. Other species use that structure for their own purposes (e.g., to hide, to await prey, etc.).
Steve Lonhart, NOAA
I don’t remember any freshwater outflow at Alki Point or Golden Gardens, but even if there was any fw outflow, the lateral distribution and depth distribution would suggest that it was not influential.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
This species was not observed in Dives on Bowie Seamount
Doug Swanston, Diver Seacology
No freshwater outflows on the reefs that I know but seasonal freshwater run off coming form the steep slopes adjacent to the reefs. As the sand allows them to attach to substrate the mud and sand are the main abiotic features.
Peter Mieras, Diver
do not generally recall fresh water outflows, but do see the sea pens up east side of Vancouver Island off Qualicum, and out around Hornby Island and inside Denman isl.
Mike Tonnesen, Diver
Near a septic tank outpipe and dock. Also in a shallow bay with some freshwater outflows at head.
Melva Nikki van Schyndel, Naturalist in Echo Bay
Kingcome and Wakeman Rivers have a strong influence in the environment; the water is often quite brackish and brown.
Bill Procter, Broughton Archipelago
The pens are common in estuarine situations, but as far as being directly bathed in fresh water, no.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
I don't recall seeing them near any substantial freshwater inputs. They seem to be in areas with good water circulation - little or no accumulated silt or detritus- but not areas with really strong currents, except juveniles as noted above.
Dr. Greg Jensen, Uni of Washington
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 32 - November 2014
13 Do you believe that any of the previously-mentioned abiotic (non-living) factors dictate where P. gurneyi choose to aggregate? Please explain.
Substrate and current seem to be the main factors
Dr. Chris Harvey-Clarke, UBC
Yes, I believe that some of the previously-mentioned abiotic factors may dictate where P. gurneyi choose to aggregate. It appears that P. gurneyi require a certain thickness of soft sediment for anchoring themselves against currents, and also to escape from predation, as they will "dig" themselves in as soon as they have been disturbed. Thick layers of soft sediment are typically found in high sediment environments (e.g., estuaries) in regions of low slope and low rugosity. Since P. gurneyi are filter feeders, a moderate to strong current is probably preferred, as this increases the rate at which "food" particles are brought to the organisms by the currents.
Dr. Barb Faggetter, 'Ocean Ecology'
Sandy substrate is very important. I know they can live in quieter waters as well.
Dr. David Cowles, Walla Walla Uni Prof
Silty sand sediments are obviously the preferred sediment type for P. gurneyi, but because individuals and low-density populations occur in a variety of sediment types (e.g., silty gravel pockets in rocky habitats), this not an absolute habitat controlling factor.
Michael Kyte, Senior Marine Biologist
Yes, sand, mud, current, and freshwater seem to be correlates.
Dr. Dennis Willows, Uni of Washington Prof
N/A
Dr. Gary Williams, PhD, Curator Invert Zoology
Absolutely. I do not know how the settlement behaviors produce it, but the patchy distribution clearly suggests some factors might be favorable for targeting settlement. I doubt flow alone, because there are many sites with similar flow and inappropriate substrate. Thus, I would hypothesize substrate cues, conspecific cues or community-member cues might all contribute, possibly with the addition of flow cues.
Dr. Russell Wyeth, St FX asst. Prof
Yes. Because P. gurneyi tends to be a non-motile filter feeded the availability of nutrient rich currents are essential. Colonies are smaller and more dispursed as current levels drop.
Jim Cosgrove, Royal BC Museum
Substrate is likely a predictive variable for P. gurneyi aggregations.
Pat Malecha, NOAA Marine Ecology & Stock Assess
Here they live in silty bottoms. I never see them on rocky bottoms or on walls. They tend to like gentle slopes and silt!
Annette Smith, Underwater Photographer
I’d love to hear your final report on this question! I’ll just say again, I do believe they tend to aggregate around freshwater inflows.
Dr. James Murray, California State Uni
Yes- at least some current flow seems to be required to thrive. I would say ‘lack of siltation’ may also be a ‘preferred’ environment, given highest ‘observed’ concentrations have been away from (as in not within the silty waters) from heavy mineral siltation
John deBoeck, Director of Dive Industry Asstn of BC
I do not have enough information to answer this.
Chad King, NOAA
Sand, low flow, shallow depth, high shell content.
Jackie Hildering, Diver
It’s likely they are not tolerant of low oxygen
Dr. Verena Tunnicliffe, UVic Prof
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 33 - November 2014
I have never seen them on rocks. I believe they are limited to sandy habitats, but not sure if there is a limit due to grain size. I am not aware of other abiotic factors that may influence its distribution.
Steve Lonhart, NOAA
No. See answer 12.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Current
Doug Swanston, Diver Seacology
See my previous comments
Peter Mieras, Diver
No...flatter sandy soft bottoms seem to be where they like to aggregate.
Mike Tonnesen, Diver
No
Melva Nikki van Schyndel, Naturalist in Echo Bay
Unsure
Bill Procter, Broughton Archipelago
Yes, the sediment is of paramount importance. The major factors are probably sediment particle size distribution and percent organic matter.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Yes, I suspect they don't handle low salinity very well. Areas with very low currents probably don't deliver enough food to the colonies, and those with really strong currents probably uproot them.
Dr. Greg Jensen, Uni of Washington
14 Are you aware of, or have any hypotheses regarding additional abiotic (non-living) environmental characteristics that may control P. gurneyi distribution and fitness?
No
Dr. Chris Harvey-Clarke, UBC
P. gurneyi apparently feed primarily on phytoplankton; their bright orange colour is the result of carotenoids derived from a diet of dinoflagellates [Best, B.A. 1988. Passive suspension feeding in a sea pen: effects of ambient flow on volume flow rate and filtering efficiency. Biol. Bull. 175:332-342.]. Since the majority of large P. gurneyi aggregations that I have seen have been in the euphotic (sun-lit) zone from 10 m to 30 m, I would suggest that light, which is required for phytoplankton growth, may also be an additional abiotic factor that may control P. gurneyi distribution and fitness.
Dr. Barb Faggetter, 'Ocean Ecology'
No
Dr. David Cowles, Walla Walla Uni Prof
I am familiar with most if not all of the literature on P. gurneyi, and know of no hypotheses or theory about environmental characteristics that control P. gurneyi other than sediment type and adequate water flow with good plankton resources.
Michael Kyte, Senior Marine Biologist
No
Dr. Dennis Willows, Uni of Washington Prof
An appreciable current or water movement is necessary.
Dr. Gary Williams, PhD, Curator Invert Zoology
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 34 - November 2014
I would hypothesize that substrate disturbance, suspended sediment, and large salinity fluctuations would all be detrimental to P. gurneyi. I would hypothesize that nutrient input, in so far as it leads to increased plankton might benefit P. gurneyi (but only if nutrient load is low enough and flow high enough that the substrate does not begin to support fungal colonization or even anoxia). Anything affecting Hippasterias distributions, and possibly Armina distributions would also likely have substantial conseqences on P. gurneyi. Tritonia also, but less so.
Dr. Russell Wyeth, St FX asst. Prof
I am unaware of the literature related to P. gurneyi and its environmental requirements such as salinity, contaminants, etc. but any change in those factors that moves the environment away from optimal will have a negative effect on the fitness and distribution of the colony.
Jim Cosgrove, Royal BC Museum
No
Pat Malecha, NOAA Marine Ecology & Stock Assess
No
Annette Smith, Underwater Photographer
Yes, I hypothesize that they are found in shallower water because they depend on higher currents. At greater depth there is lower current levels, and perhaps less plankton. Maybe this is a reason why sea pens are not found deeper and are supplanted by sea whips.
Dr. James Murray, California State Uni
No
John deBoeck, Director of Dive Industry Asstn of BC
I do not have enough information to answer this.
Chad King, NOAA
Hypothesis: Sand and high shell content substrate and low flow. Often shallow water.
Jackie Hildering, Diver
No
Dr. Verena Tunnicliffe, UVic Prof
I would think grain size and flow would be important, since the feeding structure is relatively fragile and could not withstand high turbidity loads and water forces that could scour soft tissues.
Steve Lonhart, NOAA
I am unaware of any.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Able to proliferate in waters with periodic significant fine particulates loading.
Doug Swanston, Diver Seacology
Possibly pollution in the substrate may diminish density or presence of the orange seapen
Peter Mieras, Diver
No
Mike Tonnesen, Diver
No
Melva Nikki van Schyndel, Naturalist in Echo Bay
No
Bill Procter, Broughton Archipelago
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 35 - November 2014
Current flows and sediment types are intimately intertwined in helping determine the distribution of the pens.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
None come to mind
Dr. Greg Jensen, Uni of Washington
PART C. ASCRIBED VALUE
15 Do P. gurneyi (or sea pens in general) hold any specific traditional or cultural role for you? Please explain.
They have an intrinsic role as part of the overall marine biodiversity here in the PNW. As well as a giant species they form part of the general trend to giantism seen in some PNW taxa which I think helps support their uniqueness and special ecological value.
Dr. Chris Harvey-Clarke, UBC
No
Dr. Barb Faggetter, 'Ocean Ecology'
No
Dr. Chris Harley, UBC Associate Prof
Not traditional or cultural
Dr. David Cowles, Walla Walla Uni Prof
No
Michael Kyte, Senior Marine Biologist
No
Dr. Dennis Willows, Uni of Washington Prof
The animals I study (primarily Tritonia) depend critically on sea pens as prey. I would have to change my research focus if sea pen beds disappeared.
Dr. Russell Wyeth, St FX asst. Prof
No
Jim Cosgrove, Royal BC Museum
No
Pat Malecha, NOAA Marine Ecology & Stock Assess
No. Other than they are quite beautiful to see underwater. They are also awesome at night when you can watch them sparkle if you run your fingers up them.
Annette Smith, Underwater Photographer
No cultural value per se, but they are beautiful and a sea pen forest is a fantastic place to visit!
Dr. James Murray, California State Uni
Yes- largest octo-coral / soft coral species in B.C. and UW photographers love them They ‘bio-luminesce’ when stroked gently at night
John deBoeck, Director of Dive Industry Asstn of BC
No
Chad King, NOAA
No
Jackie Hildering, Diver
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 36 - November 2014
No
Dr. Verena Tunnicliffe, UVic Prof
No
Steve Lonhart, NOAA
No
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
No
Dr. David Arsenault, BMSC
Beautiful organism
Doug Swanston, Diver Seacology
The orange sea pen is an attractive part of the entire marine ecosystem that supports our business. Divers and underwater photographers pay money to dive and see them.
Peter Mieras, Diver
No, just enjoy and observe, always enjoyed by sport divers and photographers
Mike Tonnesen, Diver
No
Melva Nikki van Schyndel, Naturalist in Echo Bay
They are unique and very beautiful and rare.
Bill Procter, Broughton Archipelago
Yes, they are one of the neatest animals around. Cool critters.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
No
Dr. Greg Jensen, Uni of Washington
16 Is it important for you to know that P. gurneyi (or sea pens in general) simply exist, even if they do not play a role in your culture/lifestyle (ie. existence value)? Please explain.
Yes, see above
Dr. Chris Harvey-Clarke, UBC
Yes. Biological diversity and natural habitats have high intrinsic value for me.
Dr. Michael Hart, SFU
Yes. I believe all organisms have important roles to play in the ecosystem, whether we understand those roles or not. Therefore, it is important to me that all organisms exist and create the complex web of life that is a part of our ecosphere.
Dr. Barb Faggetter, 'Ocean Ecology'
Yes. They are very unique animals. And beautiful.
Dr. Chris Harley, UBC Associate Prof
Yes
Dr. David Cowles, Walla Walla Uni Prof
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 37 - November 2014
Yes it is important to me to know that P. gurneyi and sea pens in general exist. I am a professional zoologist, marine biologist, and natural historian. Sea pens and other invertebrates have been a central part of my life since I was a young teen-ager. These organisms are an essential part of my environment that I enjoy directly when I visit the shore and vicariously through various media. Indeed, I have chosen the geographical area in which I live because of the presence of such organisms as sea pens.
Michael Kyte, Senior Marine Biologist
Yes because they are sole food source for nudibranchs that are important in my research.
Dr. Dennis Willows, Uni of Washington Prof
Absolutely yes. I appreciated and value all of nature’s diversity.
Dr. Russell Wyeth, St FX asst. Prof
All life has value. The loss of P. gurneyi would likely result in negative impacts for nudibranch. One has only to look at all the species that have gone extinct in the half billion years whether due to natural acts or due to human acts. How ironic is it that the state flag of California is the Golden Bear? Humans drove that species extinct. Now we spend millions and millions of dollars to conserve endangered species of no more consequence than P. gurneyi. Why would we even consider an action that would cause a species to go extinct regardless of what the benefits might be?
Jim Cosgrove, Royal BC Museum
Yes, in the sense that they are part of the benthic ecosystem.
Pat Malecha, NOAA Marine Ecology & Stock Assess
Yes. Sea pens provide habitat for other critters. They also provide food for other critters. Tochuinas that live in the sea pen forests are huge compared to the tochuinas you see elsewhere.
Annette Smith, Underwater Photographer
Yes, their basic body form has been in the fossil record for 500 million years. They are one of the first successful animal types.
Dr. James Murray, California State Uni
Perhaps for purposes of ecosystem stasis.
Chad King, NOAA
Yes! I believe that they are important in the marine ecosystem, representing very significant biomass and being a key prey item for multiple species e.g. the sea slug species I have mentioned. Likely you have seen this summation of research? http://reefkeeping.com/issues/2005-08/rs/feature/index.php I very much believe too “ In many respects, Ptilosarcus gurneyi in sea pen beds fill an ecological position similar to the huge herds of bison that used to occupy the American Great Plains, or to the grazing animals of the Serengeti. In each of these cases, whole food webs were built upon the basic keystone resource species.”
Jackie Hildering, Diver
They are likely significant as ecological engineers and in the provision of ecosystem functions such as flow modification and shelter
Dr. Verena Tunnicliffe, UVic Prof
Yes. I am a marine ecologist working for the Federal government, and understand these organisms play a role in the benthic, soft-sediment community. It is a shame they are so poorly understood, but that does not make them unimportant.
Steve Lonhart, NOAA
Yes.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Yes, as I am a strong believer in maintaining biodiversity
Dr. David Arsenault, BMSC
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 38 - November 2014
It is important to respect the habitat created by P. gurneyi as well as the locations were these organisms exist.
Doug Swanston, Diver Seacology
YES see my previous answer
Peter Mieras, Diver
one of the more colorful things to see while diving, along with the variety of nudibranchs
Mike Tonnesen, Diver
Yes, I often try to show people sea pens on my encounter tours here in Echo Bay as they really capture the imagination and their life story is quite fascinating.
Melva Nikki van Schyndel, Naturalist in Echo Bay
Yes, see above
Bill Procter, Broughton Archipelago
Yes. These are beautiful organisms and a favorite for recreational divers in particular.
Dane Stabel, Diver
Of course.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Yes- they're interesting organisms themselves and support an interesting assemblage of other animals.
Dr. Greg Jensen, Uni of Washington
17 Are you aware of, or have any hypotheses regarding important ecosystem functions (physical, chemical, and biological processes/attributes that contribute to the ecosystem) attributable to aggregations of P. gurneyi?
Interest in chemical signaling and bioactive molecules in cnidaria including this species
Dr. Chris Harvey-Clarke, UBC
Large individuals of P. gurneyi can filter over 100,000 particles/s. A dense bed of P. gurneyi could have significant impacts on populations of phytoplankton and zooplankton in the region over the bed. Thus, they may have some local impact over phytoplankton and zooplankton population densities through "bottom-up" control. Additionally, dense beds of P. gurneyi provide food for other organisms (nudibranchs and sea stars, for example), as well as refuge/habitat for some commercial organisms (Dungeness crab, rockfish).
Dr. Barb Faggetter, 'Ocean Ecology'
A general theory that should apply is that of ecosystem engineering. In other words, sea pens provide habitat structure, both above and below the sediment surface.
Dr. Chris Harley, UBC Associate Prof
P. gurneyi definitely provide structure to the ecosystem they inhabit, plus are a source of food for several predators.
Dr. David Cowles, Walla Walla Uni Prof
As remarked on by Dr. Ron Shimek (see Question 18) and me (2001), a dense aggregation of P. gurneyi is a biomass-rich environment that as a “keystone” species supports a diverse group of predators. In addition, an aggregation of P. gurneyi provides a relatively “rough” texture environment that provides shelter to another group of species (e.g., juvenile rockfish and flatfish). Another aspect is that a dense aggregation of P. gurneyi will affect water flow velocities at the water-sediment interface modifying the benthic environment. However, none of these factors have been published or written in the form of a formal hypothesis or theory regarding ecosystem functions. Indeed, sea pens have been noted as large Infauna but otherwise largely ignored in the marine biological scientific literature except for their taxonomy. Dr. Ron Shimek probably has described this situation best by his statement “This species is as typical of the Pacific Northwest as apples and sasquatch, and yet it is almost as unknown as the giant Palouse earthworm. And that is a pity!” I fully agree with his sentiment.
Michael Kyte, Senior Marine Biologist
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 39 - November 2014
No
Dr. Dennis Willows, Uni of Washington Prof
No, but this is solely due to lack of attention. I can only think of Metridium anenomes as candidate for a suspension feeder with larger planktonic predation. Given sea pen densities in some locations I would hypothesize that have relatively strong effects on plankton and thus ramifications through marine food webs in those locations.
Dr. Russell Wyeth, St FX asst. Prof
This is not my area of research but I am willing to speculate that the loss of P. gurneyi from a habitat would also result in the loss of other species.
Jim Cosgrove, Royal BC Museum
I do not know of their ecosystem function but they likely provide habitat, in the form of vertical structure, for fish, and invertebrates.
Pat Malecha, NOAA Marine Ecology & Stock Assess
I am not a scientist…..just a diver who has been diving in the area for years.
Annette Smith, Underwater Photographer
I assume that since they eat plankton, they are important in nutrient cycling. But as they are likely toxic to most species, they directly support only a few species of predators and do not provide habitat to many other species as does eel grass.
Dr. James Murray, California State Uni
No
Chad King, NOAA
Very significant biomass making the energy of plankton available to the species’ predators. Behaviour of “expanding and contracting” several times a day may have impact on the substrate for other organisms.
Jackie Hildering, Diver
They are likely significant as ecological engineers and in the provision of ecosystem functions such as flow modification and shelter
Dr. Verena Tunnicliffe, UVic Prof
Almost certainly they provide biogenic habitat.
Steve Lonhart, NOAA
No
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
No
Dr. David Arsenault, BMSC
They sustain important food webs. Some of the organisms in the food web provide import functions for humans including providing value to a diverse range of human endeavors including Neurobiology
Doug Swanston, Diver Seacology
No but I assume if you ask a researcher that specializes in this species may help you
Peter Mieras, Diver
No
Mike Tonnesen, Diver
No
Melva Nikki van Schyndel, Naturalist in Echo Bay
I think that they filter things out of the water.
Bill Procter, Broughton Archipelago
I presume that they drastically influence current flow over the substrate. I have already mentioned their bioturbatory effects.
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
I suspect dense beds (when extended) have a significant effect on water flow close to the substrate, which could influence settling invertebrate larvae. They could also be important predators on invert larvae, including larval geoducks.
Dr. Greg Jensen, Uni of Washington
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 40 - November 2014
20 Is there any other information regarding P. gurneyi that you would like to add? Please explain.
Sea pens have been declining in Puget Sound. Some researchers who used to work on them there (e.g., near Golden Gardens State Park in Seattle) can’t find them in such abundance, if at all. Not sure if that is also true in the Strait of Georgia, but it does at least suggest that this species might be one of conservation concern.
Dr. Chris Harley, UBC Associate Prof
It is notable that Birkeland (1968:10) stated “In general, then, Ptilosarcus is never sparse.” This statement was verified by Birkeland at a number of locations in Puget Sound. Thus, it is somewhat alarming that since approximately 1980, that I have found the P. gurneyi populations in all of Birkeland’s original study areas to be sparse and only a relatively small fraction of their original density (Kyte 2001). However, the population that I recently observed on the west side of Ketron Island in South Puget Sound appeared to be nearly as dense as those studied by Birkeland. The only other location that may have dense P. gurneyi populations is Dash Point near Tacoma, Washington. This location is near the entrance to South Puget Sound. Wyeth et al. (2006) observed the P. gurneyi predator Tritonia diomedea at this location and their photographic material shows a relatively dense P. gurneyi population.
Michael Kyte, Senior Marine Biologist
I have a number of tables and maps indicating both possible and known sites in the San Juan Islands and Puget Sound.
I would very much like to see a report, particularly something gives a summary of known sea pen bed locations. It would be invaluable in my research.
Dr. Russell Wyeth, St FX asst. Prof
You may like to contact Mr. Kelly Sendall (Manager of Natural History) at the Royal British Columbia Museum at (250) 387-3544 and ask him for a copy of all the Museum’s data for P. gurneyi. They may have some interesting data for you.
Jim Cosgrove, Royal BC Museum
I would be delighted to dive areas with someone, if they wanted to see our sea pen forests.
Annette Smith, Underwater Photographer
They do seem quite resilient to normal predation and the Tacoma WA site was very near a SuperFund site and yet the pens seemed quite healthy.
Dr. James Murray, California State Uni
I have emailed a map of observations and the corresponding spreadsheets, which entail depth, lat/long, and in some cases, links to videos or photos. **SEE SERVER
Chad King, NOAA
It is really important to realize how little is known about the species, how important its biomass is, that it seems to be a key prey item to multiple species, that it is often in the shallows where it is particularly susceptible to the impacts of urbanization (chemical, physical disturbance), and – that research indicates in needs low flow areas whereby any development impacting flow is highly likely to have an impact (again particular susceptibility in the shallows).
Jackie Hildering, Diver
For an approach to studying fish/coral relationships, you may be interested in:
Du Preez, C., and V. Tunnicliffe. 2011. Shortspine thornyhead and rockfish (Scorpaenidae) distribution in response to substratum, biological structures, and trawling. Marine Ecology Progress Series, 425: 217-231.
Dr. Verena Tunnicliffe, UVic Prof
It is all in Birkeland 1974. You cited it so I assume you have a copy. If you need a copy, let me know.
Dr. Charles Birkeland, PhD, Prof (Uni Guam Marine Lab)
Port Metro Vancouver APPENDIX C Hemmera RBT2 – Orange Sea Pens - 41 - November 2014
do spend about 60 to 70 days in the water in lots of areas of the coast, May to Sept, at Langara, and March in the French Creek area north to Cape Lazo, spawn herring ass. and Oct, cuke harvesting Campbell River north, Nov, Dec in Victoria Sidney
Mike Tonnesen, Diver
My consulting rate is US$100/hour; maybe you should hire me for a few (dozen J ) hours
Dr. Ron Shimek, Prof, UW Friday Harbour Lab, BMSC etc
Beds don't seem to be a stable feature. They seem to persist for a couple decades and eventually get wiped out by predators; in the meantime new beds pop up (and many blink out while still juveniles) but some eventually take hold. I think many of the juvenile beds succumb to non-specialist predators like Hermissenda.
Dr. Greg Jensen, Uni of Washington