prototype biophysical maps of the gulf maine · having the data available and having them connected...

PROTOTYPEBIOPHYSICAL

MAPSOF THE

GULF OF MAINE


MAPSOF THE

GULF OF MAINE

Gulf of Maine Area ProgramGulf of Maine Area Program

Gulf of Maine Area Program


MAPSOF THE

GULF OF MAINEPrepared by the Island Institute

Evan Richert and Lewis Incze, editorsGulf of Maine Program of the Census of Marine Life

University of Southern Maine • Portland, Maine

October, 2003

This document was prepared with the support of the Davis Conservation Foundation, the National Fish and Wildlife

Foundation and the Alfred P. Sloan Foundation

The Census of Marine Life is a growing global network of researchers in more than 45 nations engaged in a 10-year initiative to assess and explain the diversity, distribution and abundance of life in the oceans — past, present and future. The Gulf of Maine Program is one of seven initial field projects of the worldwide Census of Marine Life.

Production by the Island Institute:Project Management: Christopher Brehme;

Data Management: Liv Detrick; Layout & Design: Charles G. Oldham;Editing: David D. Platt; Project Assistants: Benjamin Neal, Leslie Fuller

Cartography:Bill Duffy, Northern Geomantics

and Christopher Brehme, Island Institute

We would like to thank the following contributorsfor their considerable efforts in creating this document:

Peter Stevick, New England AquariumTora Johnson, College of the Atlantic

Diane Cowan,The Lobster ConservancyTom Shyka, Gulf of Maine Ocean Observing System

Josie Quintrell, Gulf of Maine Ocean Observing SystemPhilip Bogden, Gulf of Maine Ocean Observing System

Sarah Kirn, Gulf of Maine Research InstituteAnnette deCharon, Bigelow Laboratory for Ocean Sciences

Bob Houston, US Fish and Wildlife ServiceGerhard Pohle, Huntsman Marine Science Centre

Nick Wolff, University of Southern MaineBen Cowie-Haskell, Stellwagen Bank National Marine Sanctuary

Linda Mercer, Maine Department of Marine ResourcesSusan Farady, Ocean Conservancy

Ted Ames, Stonington Fisheries AllianceAnne Hayden, Resource Services

Paul Schroeder, University of MaineSteve Cousins, University of Maine

Bob Bowman, Center for Coastal Studies / Maine

ACKNOWLEDGEMENTSACKNOWLEDGEMENTS

PROTOTYPE BIOPHYSICAL MAPS OF THE GULF OF MAINE

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Changes in right whale habitat utilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Distribution and movement in relation to habitat requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 10

“Churchill”:The story of right whale #1120 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Paralytic Shellfish Poisoning: How Gulf-wide forces produce local effects . . . . . . . . . . . . . . . . . . . 17

Large-scale migratory movements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Distribution of lobster postlarvae: Relationships to coastal currents

& effects on lobster population dynamics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Mapping the movements of egg-bearing female lobsters and bottom temperatures . . . . . . . . . . . 26

Northern shrimp: How maps tell two stories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Selected readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

TABLE OF CONTENTSTABLE OF CONTENTS

Natural Regions of the Gulf of MaineNatural Regions of the Gulf of Maine

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INTRODUCTION

“... fisheries, embedded as they are in natural ecosystems, andrelying as they do on natural fluxes of these systems, depend onthe features of places. Thus, while we emphasize the variability offisheries in time, we tend to lose track of their variability in space... Indeed, we hardly use maps to discuss fisheries (except fortunas). Maps, clearly, will be an important part of ecosystem-based management ...”

— Daniel Pauly, Reg Watson and Villy Christensen

In their recent essay on "ecological geography," Pauly,Watson and Christensen (2003) argue that advances incomputer and mapping technologies will allow maps to once again become intuitive sources of information aboutmarine life and its relationships to the physical setting. Many kinds of users, including policy makers and the publicat-large, need maps to be able to absorb knowledge of the oceans and to participate meaningfully in the develop-ment of oceans policy. For scientists, maps are useful to quickly explore information and ideas.

In the Gulf of Maine, maps richly endowed with information and aimed at resource managers, policy makers,and the public already are in use.These include, for example, the Island Institute's Environmental Atlas of the Gulfof Maine, the new edition of Bigelow and Schroeder's Fishes of the Gulf of Maine, the real-time web site of theGulf of Maine Ocean Observing System, the "high conservation value areas" mapping project of the ConservationLaw Foundation and World Wildlife Fund-Canada, the Ocean Conservancy's atlas of coastal protected areas, multi-beam seafloor mapping of portions of the Gulf of Maine, and satellite images that map the distribution of sea sur-face temperature and other characteristics of the Gulf over time and space (see references).

The mapping of the Gulf of Maine, however, has been limited by an inability to combine layers of related data-especially biological with physical-to create composite pictures. Now that is changing. In fact, the evolution ofgeographic information systems (GIS) and Internet technology potentially will allow persons interested in theoceans to build maps on demand — using any combination of physical and biological features for which data areavailable.

The Gulf of Maine Census is taking advantage of these technologies and intends to produce an electronicDynamic Atlas of the Gulf of Maine: an on-line atlas that allows users to visually link a great variety of data fromdifferent sources.While this tool will not be a replacement for critical evaluation of original data, it will greatlyfacilitate the surveillance and use of those data. For resource managers, educators, and industry, it will provide anew opportunity to explore patterns of life in the Gulf of Maine.

As Pauly et al. note in their essay, a number of issues will have to be sorted out before maps become a rou-tine tool in fisheries and marine ecosystem sciences.The world of oceanography is relatively inexperienced atmapping multiple types of data collected at different times and with varying spatial resolution, and from that draw-ing conclusions about ecological patterns. Put simply, we're not quite sure about the appropriate statistics wherethe ecosystem boundaries are fluid, data are often uncomfortably sparse, and the marine environment works atmany scales of time and space.What is becoming routine in the application of GIS on land is still a novelty withmuch uncertainty regarding its application to thesea.

The Gulf of Maine Census is creating the Dynamic Atlas in stages.At present we are actively bringing fish-eries and other environmental data sets for the Gulf of Maine from DFO-Canada, the U.S. National FisheriesMarine Service, and other sources into a system we are calling the Gulf of Maine Biogeographic InformationSystem (GMBIS).This system includes a GIS-based visualization tool, known as the Environmental Analysis System(EASy), developed for use across the Internet. It also will include community-standard protocols for data explo-ration and downloading from other systems.We envision this as a major biological component of the Gulf of

INTRODUCTION

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ensus of Marine Life

Maine Ocean Observing System.Having the data available and having them connected to a visualization tool capable of creating maps via the

Internet does not automatically make the system useful, however. Given all the gaps in data and the challenges ofthe marine environment, is it nevertheless possible to construct maps that illustrate issues of, suggest hypothesesabout, or explain the abundance, diversity, and distribution of life in the Gulf of Maine? What kinds of cautions areneeded to help non-scientists avoid misleading conclusions? What kinds of presentations — graphically, statisticallyor otherwise — would allow the maps to summarize knowledge in robust and useful ways? Can the tools ofinformation technology lead users to the kinds of presentations that will be meaningful to them? Will these pre-sentations advance our thinking and management?

The prototype biophysical maps that make up this volume explore these questions.They are mock-ups inadvance of a Dynamic Atlas to see whether and how maps, using available layers of data on the Gulf of Maine, canbe constructed to accurately frame an issue, relate a theme, or describe known relationships between an organ-ism and its physical, chemical and biotic surroundings.They also serve the purpose of signaling the types of"threshold" gaps that must be overcome in the course of the Gulf of Maine Census to make this type of analyticaltool useful.

In this small volume, we explore the issues around biogeographic map-making in the Gulf of Maine using sev-eral themes as test cases. It is a learning document, illustrating the kinds of mapped connections that can be madewithin current limits of data on the Gulf and underscoring the need to fill some serious gaps in information if weare to truly understand the Gulf of Maine as an ecosystem.

Evan Richert, Program DirectorLewis Incze, Chief Scientist

Gulf of Maine Census of Marine LifeUniversity of Southern Maine

References

Collette, B. B., and G. Klein-MacPhee, eds. 2002. Bigelow and Schroeder’s Fishes of the Gulf of Maine,ThirdEdition. Smithsonian Press,Washington, D.C.

Conkling, P., 1995. From Cape Cod to the Bay of Fundy: An Environmental Atlas of the Gulf of Maine. MIT Press,Cambridge.

Gulf of Maine Mapping Initiative. See www.gulfofmaine.org, http://woodshole.er.usgs.gov/project-pages/stellwagen,http://www.ccom.unh.edu/index.htm, http://seamap.bio.ns.ca, http://www.omg.unb.ca/omg.

Gulf of Maine Ocean Observing System, www.gomoos.org

Pauly, D.,Watson, R. and Christensen,V., 2003.“Ecological Geography as a Framework for a Transition TowardResponsible Fishing,” in Responsible Fisheries in the Marine Ecosystem, ed. M. Sinclair and G.Valdimarsson. Foodand Agriculture Organization of the United Nations.

Ocean Conservancy, 2001. Marine and coastal protected areas in the United States Gulf of Maine region. 96 p.The Ocean Conservancy,Washington, D. C.

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Changes inright whalehabitatutilization

Marine animals spend the majority oftheir lives in areas associated with one ormore of the resources that they need.Theseresources help to define their habitat, and dif-ferent habitats may be associated with differ-ent resources. Oceanographic processes arecomplex, however. Conditions may change, andthe resources that cause an area to constitutegood habitat may suddenly become scarce.This lack of predictability leads to dramaticand sometimes sudden changes in the distribu-tion of animals.

During summer months, the majority ofthe critically endangered North Atlantic rightwhale (Eubalaena glacialis) population isfound in the northern Gulf of Maine.Theseanimals primarily occur in a limited number oflocalized feeding habitats. Copepods, principal-ly the older life stages of Calanusfinmarchicus, are the most important food forright whales in the Gulf of Maine. Right whalesmust exploit very dense concentrations ofthese in order to obtain adequate prey.Densities of more than 10,000 zooplanktonper cubic meter of seawater have beenrecorded in the presence of feeding rightwhales; indeed these animals appear to requiresuch concentrated swarms for successful for-aging. Copepod aggregations this extreme willpredictably occur only where oceanographicconditions produce high primary productivityand also lead to the concentration of plank-tonic organisms. In the mouth of the Bay ofFundy, the exceedingly large tidal range leadsto strong, tidally-induced vertical mixing and aresulting high level of primary production, witha concentration of zooplankton along theboundary of the mixed layer.To the south ofNova Scotia the prevailing current flowingwest into the Gulf of Maine encounters theshoal waters of Browns Bank, also resulting invertical mixing, high levels of primary produc-tion and concentrations of zooplankton.Thesetwo sites comprise the primary habitats for

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Habitat Utilization,1990Habitat Utilization,1990


Changes inright whalehabitatutilization

right whales in the northern Gulf of Maine.From the time these aggregations were

identified in the late 1970s and early 1980s,right whales were found in considerable num-bers in both of these habitats each summer.This condition is reflected in the distributionduring 1990 and 1991. Quite abruptly in 1992the number of right whales on Browns Bankdeclined dramatically while an increase in thenumber of animals in the Bay of Fundy wasobserved. By 1993 there were virtually noright whales using the Browns Bank area.

Right whales can be distinguished fromone another by variation in markings, princi-pally around the head.Thus it is possible todistinguish the movements of individual ani-mals and the results show how different ani-mals utilize these habitats. Many individualwhales used both regions; some were identi-fied in both during the same season.Theseindividuals largely summered in the Bay ofFundy following the declines on Browns Bank.Some whales, however, were quite specific to agiven habitat, were only identified there andreturned regularly. Some individual whaleswere only seen to forage in the Bay of Fundyarea, even during the peak of activity atBrowns Bank. Other individuals were onlyseen on Browns Bank and have rarely beensighted since the abandonment of that area.They may have shifted to other offshore banksin a remote location where they have not yetbeen discovered.Another possibility is thatthey now forage primarily in deep water farfrom shore where the boundaries of currentsmight also serve to concentrate prey.

This change in whale distribution mostlikely reflects a change in the abundance ordistribution of copepods near Browns Bank, asabandonment of an area where foraging isproductive seems improbable. In situationswhere prey is abundant, oceanographic oranthropogenic changes are not likely toexplain the observed change in behavior;indeed a major shipping lane runs through theBay of Fundy habitat without apparent influ-ence on whale distribution. Right whale forag-ing success — and thus habitat use — couldbe influenced by declines in the overall bio-mass of copepods in the region.Abundancecycles are driven by many factors includingfood limitation, competition and predation.Large declines in copepod biomass need notoccur to influence right whale foraging;

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changes in distribution that result in lowerconcentration and fewer dense swarms wouldalso influence the suitability of the area forright whales.A local increase in abundance orrecent influx into the region of a copepodpredator, for example, could disperse thedense concentrations required by right whales.

Few data are available to identify theunderlying causes of the distribution changeand to distinguish between different possiblemechanisms. Direct measurements of copepodnumbers are not available to determine if theydeclined in abundance during this time. Even ifbroad-scale plankton survey data were avail-able for these years, they would not necessari-ly predict localized changes in density orswarming behavior. Similarly, information onoceanographic conditions that may influenceproductivity and distribution of animals in thearea is limited.The scale at which oceano-graphic sampling is most often conducted andthe resolution of remote imaging techniquescomplicate their application to studies ofchanges on small scales. Subtle oceanographicchanges may cascade into dramatic changesfor animals, and complex, difficult to interpretspatial relationships are likely to be involved.While whales may serve as a visible indicatorof ecosystem change, the underlying mecha-nism of that change may remain hidden with-out further directed sampling.

Whale sightings represent individual rightwhales identified by natural markings duringJuly,August and September. Only a singlerecord of each individual is presented for eachregion during each year.While these data arenot corrected for effort, comparable surveyeffort occurred on Browns Bank during eachof these years, so the observed decline inabundance does not indicate a lack of effort inthis region.

— Peter Stevick,New England Aquarium

Data are from the North Atlantic RightWhale Catalog. They are prepared by PeterStevick and are used courtesy of theEdgerton Research Laboratory, New EnglandAquarium, Boston, Massachusetts.

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Distribution and movement inrelation to habitat requirements

The ocean environment is highly patchy, and the distribution of animals reflects the distribution of theresources they require.These resources may be physical characteristics of the environment or they may be otherorganisms, primarily food, though distribution is also influenced by other factors, such as the presence of preda-tors. Resources may themselves also be fixed in space or transitory.They may occur predictably at certain timesof year, or they may occur on an irregular basis. Not surprisingly, animals are far from evenly distributed in theGulf of Maine.

Sand lance (Ammodytes dubius) are small fish commonly found in dense schools.They feed on zooplankton,and thus they occur in areas where currents and bottom topography lead to an overall high level of production.Furthermore, sand lance spend considerable time in their burrows on the ocean floor and require areas withsandy sediment conducive to burrowing.

Humpback whales (Megaptera novaeangliae) eat small schooling fish, and in the southern parts of the Gulf ofMaine, they prey extensively on sand lance.Where sand lance occur, the distribution of humpback whales broadlycorresponds with them. Humpback whales take a wide range of prey in addition to sand lance, however, and con-centrations to the north of Massachusetts probably most often represent individuals feeding on herring or otherspecies.

Sand lance populations do not seem to be particularly stable; their overall abundance in the Gulf of Mainechanges by orders of magnitude from year to year.The extent and timing of sand lance cycles have been shown to

Distribution and movement inrelation to habitat requirements

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10 1992 & 1993 Locations of Sand Lance in Relation to Substrate1992 & 1993 Locations of Sand Lance in Relation to Substrate

be related to the relative abundance of herring and mackerel that compete for the available zooplankton, as wellas the numbers of predators on young sand lance, most notably mackerel. Local conditions will also influencewhere sand lance are located within the Gulf of Maine from year to year. In 1992, for example, sand lance wereprincipally distributed near shore in Massachusetts Bay and around the Stellwagen Bank National MarineSanctuary. But in 1993, sand lance were scarce in this region while they were abundant along the western edge ofGeorges Bank near the Great South Channel.Also in 1993, humpback whale distribution shifted offshore, closelymatching the distribution of sand lance. Humpback whales, the evidence suggests, shifted the habitat in which theyforaged by nearly 150 km in consecutive years in response to the shifting location of their prey.

Examination at a finer scale reveals the limitations of the sand lance and humpback whale data presentedhere.To forage successfully, humpback whales require a high density of prey. Such concentrations often occuralong the edges of banks or current boundaries, even when larger but more dispersed schools may occur nearby.Similarly, humpbacks will concentrate where sand lance forage near the surface.Trawl surveys are most efficient atcatching sand lance over flat sandy bottoms where they burrow, and may not accurately report locations of aggre-gations elsewhere in the water column where humpbacks are likely to feed.Also, due to different survey designs,data on humpbacks and sand lance were not collected in precisely the same places or at the precisely the sametimes of year.The humpback whale data shown on the accompanying maps were collected during summer, whilethe sand lance data come from surveys conducted in spring and autumn. Data on herring are influenced by evenmore significant methodological inconsistencies, which led to their omission from these maps. Much of the infor-mation available for herring across the Gulf of Maine region is from the standardized NMFS spring and fall trawlsurveys, which leave out the primary season for herring aggregations, and also sample only on the bottom. Fishingvessel based acoustic surveys are underway, but are currently subject to the area choices of the vessels, which inturn are driven by market and individual choice, limiting the application of this information across a Gulf of Maine

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1992 Locations of Humpback Whales and Sand Lance1992 Locations of Humpback Whales and Sand Lance

scale.Taken together, these data suggest a biological interaction between the sighting locations of humpback

whales and the changing distribution of prey species. However, they also reflect a need for additional interaction-specific studies in order to more completely understand the habitat requirements and foraging-related move-ments of various large whale species.

Enhancing our understanding of the nature of these inter-specific relationships could support the develop-ment of ecosystem management plans that take into account all the species likely to be affected by marine regula-tions. In addition, due to the protected nature of marine mammals, specific management measures can be designedto reduce interactions between whales and fishing gear.To ensure that these are effective, future studies shouldaddress biological/geophysical connections as well as the particular inter-species interactions.

— Peter Stevick, New England Aquarium

Sand lance concentrations are presented as the catch per standardized tow made from spring and autumntrawl surveys conducted by the Fisheries Assessment Branch, Northeast Fisheries Science Center of the UnitedStates National Marine Fisheries Service.Humpback whale sighting locations are from surveys conducted July through September 1992 and 1993 by the Years ofthe North Atlantic Humpback Whale project. Data are provided courtesy of the Center for Coastal Studies and preparedby Peter Stevick.The figure is after Smith, et al. 1999. An ocean-basin-wide mark-recapture study of the North Atlantichumpback whale (Megaptera novaeangliae). Marine Mammal Science 15:1-32.

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12 1993 Locations of Humpback Whales and Sand Lance1993 Locations of Humpback Whales and Sand Lance

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“Churchill”:The story of right whale #1102

On June 8, 2001, a small surveillance plane flew low over right whales feeding in the Great South Channel atthe southern end of the Gulf of Maine. One of the whales appeared lighter in color than the others. Light skin isan indication of sickness in whales, so the plane circled lower. Peering from the plane windows, the crew couldsee rope trailing from each side of the lighter whale’s mouth.This whale had apparently encountered fishing gearand had rope wrapped around its narrow upper jaw or rostrum.

So began the saga of right whale #1102, dubbed “Churchill;” he would hold the attention of people world-wide for the next three-and-a-half months.

Scientists believe fewer than 350 right whales remain in the North Atlantic and warn that entanglements infishing gear may be contributing to their decline.The Great South Channel, bounded to the east by Georges Bankand to the west by Nantucket Shoals, has been designated a Critical Habitat Area for right whales. Strong con-verging currents here often concentrate copepods, tiny planktonic crustaceans on which the right whale feeds.The favorable conditions for fattening and concentrating copepods undergo cyclical variation, and right whale calv-ing rates rise and fall with these blooms.When conditions are most favorable, up to a quarter of the NorthAtlantic right whale population may be feeding in the Great South Channel on any given spring or summer day. Inunfavorable conditions, the whales are forced to feed elsewhere. Current research focuses on the factors thatcontribute to this boom-and-bust pattern.

June 9 — 30On June 9, a whale rescue team from the Center for Coastal Studies (CCS) in Provincetown, MA sought out

Churchill, approached the whale in an inflatable outboard boat and found that the rope had pulled so tight it hadbecome embedded in the rostrum. So even if the team could safely approach the entanglement site on the whale’s

“Churchill”:The story of right whale #1102

Track of Right Whale #1102, June 2001Track of Right Whale #1102, June 2001

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head, removing the line would be difficult and dangerous.They attached a satellite telemetry buoy to the line trail-ing from the left side of Churchill’s mouth.

The telemetry system consists of a satellite-monitored transmitter and a short-range VHF beacon carried ona 14-inch hard plastic buoy.The whale tows the buoy and the transmitter sends fixes of its location whenever thebuoy is at the surface within range of a passing satellite, allowing the CCS team to track and relocate the whale.The team cannot know the exact path the animal takes between fixes, but it can get an idea of the whale’s loca-tion, how much time he spends at the surface, and whether he is traveling or feeding. Sometimes the constantlight drag on the entangling lines helps the animal shake the gear.Telemetry allows a rare look into the rightwhale’s world, answering many questions, but raising others.

While Churchill towed his buoy and grazed on the copepods in the Great South Channel, the rescue teamworked with federal fisheries officials and veterinary specialists to develop a plan to remove the embedded rope.Given the animal’s light color and the extent of his head wound, the veterinarians believed Churchill would die ifthey did not remove the line.The team constructed a specialized syringe to inject the whale with a sedative, whichwould allow the team to cut the embedded line in relative safety. Right whales are strong and pugnacious, oftenstriking out at would-be rescuers with tail slashes or swipes of the head.

On June 26 the team found Churchill, and for the first time ever on a free-swimming large whale, administeredtwo conservative doses of a sedative, which produced no discernible effect. In fact, the whale towed the satellitebuoy and the inflatable at a steady five knots throughout the day.The drag of the buoy had indeed shifted the lineso a frayed knot now lay against Churchill’s right lip, but the knot was not likely to pull through the baleen plates inthe whale’s mouth.The team could not safely approach to cut the line, so they left Churchill late in the afternoon.

July 1 — 31Churchill remained in the Great South Channel for the first half of July.Then, on July 14, the rescue team

made another attempt.When the team located the whale, it found patches of whale lice infesting his head wound.Whale lice, or Cyamids, are small crustaceans that live on whales and nowhere else.They normally occur in mod-erate numbers on healthy whales, where they eat dead skin.They proliferate on sick whales.The team attemptedto give the whale two doses of a newly formulated sedative, but the syringe malfunctioned.Again the team could

Track of Right Whale #1102, July 2001Track of Right Whale #1102, July 2001

not remove the rope, so it returned to Provincetown.Then Churchill left the Great South Channel, and in the following two weeks swam 940 nautical miles. He

made his way east, crossing into Canadian waters on July 16, made a detour over the continental slope, and head-ed for the Gulf of St. Lawrence.

Until recently, scientists believed right whales came to feeding grounds and stayed throughout the feedingseason. However, when CCS and others began tracking right whales in the late 1990s, they discovered the whales,whether entangled or unencumbered, often roam far and unpredictably within a season, commonly returning tofeeding grounds they have recently visited. Researchers now understand that Churchill’s foray was normal behav-ior, but still cannot explain why right whales roam.

The revelation of the right whale’s wandering has led many to question the effectiveness of protecting rightwhales with area fisheries closures. Given these new tracking data, it seems right whales might move in and out ofa closed area constantly. Scientists are currently looking at other whale species in the Gulf of Maine to determinewhether they exhibit similar patterns of movement.

August 1 — 31After less than a week in the Gulf of St. Lawrence, Churchill

turned back toward the Gulf of Maine. He followed the southshore of Nova Scotia, but heavy weather and fog prevented fur-ther rescue attempts. He next roamed the edge of theContinental Shelf, frequently lingering — possibly feeding —before returning to the Great South Channel, where the CCSteam mounted another rescue effort.

On August 30, satellite telemetry led the team to Churchill less than ten miles from where he was firstreported entangled, 12 weeks earlier. His skin was now very light and peeling.Wide orange patches of whale licecovered his head and much of his body.Also, the area just behind Churchill’s head showed a distinct hollow, indi-cating he was emaciated.

The team administered three doses of the sedative and finally Churchill calmed, floating quietly in the water.

Track of Right Whale #1102,August 2001Track of Right Whale #1102,August 2001

c 2001 Center for Coastal Studies/NOAA Fisheries

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Then rescuers attempted to use a harness to restrain Churchill’s deadly tail. Before they could capture the tail,however, the sedative began to wear off. Having failed in a fourth attempt, the team replaced Churchill’s telemetrybuoy with a fresh unit and returned to Provincetown.

September 1 — 15Churchill remained in the Great South Channel for the first few days of September; then his behavior

became erratic. On September 10, when satellite telemetry showed he was spending 100 percent of his time ator near the surface, a Coast Guard jet located Churchill at the southern edge of Georges Bank. He was alive, butremained nearly motionless just below the surface.That same afternoon Churchill began to move again, travelingsteadily southwest throughout the night and into the morning of September 11. On the 12th his signal again indi-cated he was drifting near the surface. Over the next four days, Churchill moved slowly but steadily out over thecontinental slope until his signal fell silent on September 16. Scientists believe the animal had succumbed to hisinjury and sank to the depths.

In the 100 days since the team tagged Churchill on June 9, he had traveled over 4,900 nautical miles.Though Churchill’s story ended sadly, he had taught scientists a great deal.The CCS team developed and

tested valuable new rescue techniques, and Churchill’s satellite telemetry track showed that right whales can anddo travel great distances in relatively short periods of time, information that will be vital to future protectionefforts.Also, Churchill’s case served to underscore the importance of finding a preventive solution to the problemof whale entanglement.

Many questions remain. Do the Gulf of Maine’s other large whales also wander among feeding grounds?What climatic and oceanographic factors determine prey distribution in the Gulf of Maine, and how do theychange over time? The answers to these and similar questions may hold important keys to the future of the greatwhales in the Gulf of Maine.

— Tora Johnson, College of the Atlantic , and Bob Bowman, Center for Coastal Studies

Whale telemetry data courtesy of NOAA/NMFS, Center for Coastal Studies

Track of Right Whale #1102, September 2001Track of Right Whale #1102, September 2001

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Paralytic Shellfish Poisoning: How Gulf-wide forces produce local effects

The Gulf of Maine is a uniquely productive coastal ocean.This biological productivity is driven in large partby the physical dynamics of the region, which result in some of the highest levels of nutrients in a shallow coastalsea, anywhere on earth. Some physical and biological processes occur at small, local scales, while others are gulf-wide. Other seemingly local systems are driven by gulf-wide processes.The occurrence of Paralytic ShellfishPoisoning (PSP) along the coast of Maine is one such seemingly local issue that is in fact driven by gulf-wide physi-cal forces.

Paralytic Shellfish Poisoning, or Red Tide as it is commonly known, is the result of a bloom of Alexandrium,one of the many phytoplankton genera that naturally occur in the Gulf of Maine. (A “bloom” is an unusually highconcentration of a given species of phytoplankton that occurs when conditions of light, temperature, nutrients,and water energy favor its rapid growth.)

Alexandrium produces a potent neurotoxin that accumulates in shellfish that consume it.When humans eatshellfish that have been feeding on Alexandrium, we get PSP, the symptoms of which vary from tingling around themouth to full-scale paralysis, depending on the amount of toxin consumed.

Wide scale monitoring for PSP in the Bay of Fundy started in 1945 and in the State of Maine in 1957 inresponse to two large PSP incidents in these areas in the Gulf of Maine (Bond 1975; Hurst 1975).Although toxinhas been detected in shellfish by the Maine monitoring program every year since its inception (Hurst 1979), itrarely occurs in Penobscot Bay.

An apparent increase in frequency of PSP events and consequent declines in coastal shellfish harvests ledeventually to the establishment of a multi-institutional research program, Ecology and Oceanography of Harmful

Paralytic Shellfish Poisoning: How Gulf-wide forces produce local effects

PSP (Red Tide) Closure Areas on the Maine CoastPSP (Red Tide) Closure Areas on the Maine Coast

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18 Distribution of Alexandrum vs.Eastern Maine Coast Current, June 1998

Distribution of Alexandrum vs.Eastern Maine Coast Current, June 1998

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Distribution of Alexandrum vs.Eastern Maine Coast Current, July 1998

Distribution of Alexandrum vs.Eastern Maine Coast Current, July 1998

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20 Distribution of Alexandrum vs.Eastern Maine Coast Current,August 1998

Distribution of Alexandrum vs.Eastern Maine Coast Current,August 1998

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Algal Blooms in the Gulf of Maine (ECOHAB-GOM), funded by the National Science Foundation and the NationalOceanic and Atmospheric Administration.

Alexandrium was known to occur near the coast of Maine, but whether it occurred offshore was a mystery.No body of coastal water, however, is truly isolated from the ocean. Following this thinking, ECOHAB scientistsundertook a series of research cruises in the Gulf of Maine to determine whether or not Alexandrium occurredoffshore.

ECOHAB surveys found densities upwards of 4,000 Alexandrium cells per liter in the offshore waters of theGulf of Maine in late spring and early summer of 1998 (Townsend et al. 2001).This population of Alexandrium hasbeen well correlated with the Eastern Maine Coastal Current (Pettigrew et al. 1998;Townsend et al. 2001) as wellas with closures of shellfish beds to harvesting (Hurst 1979). Alexandrium’s apparent affinity to the Eastern MaineCoastal Current also apparently explains the long-standing mystery of why PSP so rarely occurs in Penobscot Bay.The map at the beginning of this section shows how few closures occurred in Penobscot Bay from 1993 — 2001,compared with locations east and west.The coastal current — as indicated by the colder sea surface temperatureson the subsequent maps — turns offshore in the vicinity of Penobscot Bay, carrying Alexandrium cells with it.

While this study documented the occurrence of Alexandrium in the Eastern Maine Coastal Current, it didnot reveal why this distribution occurs.The explanation for the observed distribution of Alexandrium may involveoptimum light levels, nutrient concentrations, trace metal concentrations, water temperatures, a lack of competi-tion, a lack of predation, water turbulence or any combination of these factors — or others not yet identified asimportant. In other words, whether the distribution of Alexandrium is due to its biological needs for light, nutrientsand water temperature and turbulence levels or the needs of its competitors or predators remains unknown.Laboratory studies have shown some individual phyotoplankton species’ biological and physical requirements forsuccess; much more remains to be learned regarding species-species interactions in an ecosystem context.

The ECOHAB broad scale survey of the Gulf of Maine revealed that a gulf-scale physical oceanographic fea-ture (the Eastern Maine Coastal Current) is a primary driver of a well-known regional biological pattern: the geo-graphic occurrence of Alexandrium and subsequent PSP events along the Gulf of Maine coastline.This examplehighlights the inextricable nature of ocean life and physical forces.

— Sarah Kirn, Gulf of Maine Research Institute

Alexandrium and sea surface temperature data are from David Townsend and the ECOHAB Program. PSP ClosureArea data are from Maine Department of Marine Resources.

References

Bond, R. M. 1975. Management of PSP in Canada. Proceedings of the First International Conference on ToxicDinoflagellate Blooms.V. R. LoCicero. Boston, Massachusetts Technology Foundation, Inc.

Hurst, J.W. 1975. History of paralytic shellfish poisoning on the Maine Coast 1958-1974. Proceedings of the FirstInternational Conference on Toxic Dinoflagellate Blooms.V. R. LoCicero. Boston, Massachusetts TechnologyFoundation,Inc.: 525-528.

Pettigrew, N. R., D.W.Townsend, H. Xue, J. P.Wallinga, P. J. Brickley and R. D. Hetland. 1998. Observations of theEastern Maine Coastal Current and its offshore extensions in 1994. Journal of Geophysical Research. 103:(C13):30,623-30,639.

Townsend, D.W., N. R. Pettigrew and A. C.Thomas. 2001. Offshore blooms of the red tide dinoflagellateAlexandrium sp., in the Gulf of Maine. Continental Shelf Research. 21:347-369.

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22

Large-scale migratory movementsAnimals do not necessarily spend their lives confined to a single geographical region or ecosystem. Individual

animals that use habitats within the Gulf of Maine may also travel extensively to regions outside it. Some animalsforage in several seasonally productive areas, moving from one to another through the year. Some Arctic terns, tocite an extreme case, nest in the Gulf of Maine during our summer months and migrate as far as the Antarctic inwinter, moving progressively through areas where food is abundant. Large predators such as sharks may followless predictable seasonal patterns, yet the scale of resource predictability they require may be larger than the Gulfof Maine, and they forage over huge areas.Tag returns indicate that some sharks cross the Atlantic. Finally, season-ally specific activities or behaviors may require different resources and therefore different habitats. Humpbackwhales exemplify this case.

Humpbacks have the longest documented migration of any mammal. During the summer months they foragein productive temperate and polar waters where they feed on dense concentrations of small schooling fish andlarge zooplankton.The whales accumulate an extensive layer of fat at this time that allows them to survive with-out eating for several months during winter. During their fast, they migrate thousands of kilometers to waters inor near the tropics where mating takes place and calves are born. It is not clear what features of this habitat aremost important, but concentrations of humpback whales occur in shallow water, often downwind of protectiveislands or reefs. Productivity is low in these areas, feeding is rarely observed and individuals lose a substantial por-tion of their body weight, so the choice of habitat does not seem to be linked to prey.

Within the North Atlantic, humpback whales concentrate for feeding in the Gulf of Maine, as well as inother areas with dense concentrations of prey, including the Gulf of St. Lawrence, and off the coasts ofNewfoundland, Labrador, west Greenland, Iceland and Norway. In winter, individuals from all of these areas con-verge on the West Indies where they concentrate at sites off the Greater Antilles islands.These areas includeSilver, Navidad and Mouchoir Banks between the Dominican Republic and the Turks and Caicos Islands, SamanaBay off the Dominican Republic and the western coast of Puerto Rico.

Individual humpback whales can be recognized and distinguished from one another by the variation in mark-ings on the tail flukes.These marks are stable and distinctive enough to serve as a natural tag useful for investigat-ing migratory movements.

The figure on the facing page shows the locations of some individual humpback whales that were identifiedby fluke markings in the Gulf of Maine in summer and also on the breeding range in winter.Whales from the Gulfof Maine have been sighted in all of the major habitats in the West Indies and do not seem to have any preferencefor a specific breeding site. Humpback whales from the Gulf of Maine and from Canadian waters have been shownto arrive in the West Indies, on average, earlier than whales that summer further east. Otherwise there is no indi-cation that animals from the same feeding area associate with one another on the breeding grounds.

The principal migratory routes for humpback whales in the North Atlantic are through the open oceanrather than near the coasts, as animals are almost never seen during migration.The exception is at Bermuda,where some are seen for a brief period each spring. Some individuals identified in Bermuda have also been seen inthe Gulf of Maine as illustrated here. Otherwise the behavior of animals on migration and the routes that theyfollow are not well understood. Unlike a transmitter tag, identification by natural markings only provides a loca-tion when an individual is photographed. Many individuals have only been identified once, and re-sightings may bemonths or even years apart, providing no information on the behavior of the animal between sightings.The linesin this figure thus serve to connect sightings of an individual animal in the different habitats that it uses, but arenot intended to represent migratory routes.

— Peter Stevick, New England Aquarium

The sightings presented here are from the North Atlantic Humpback Whale Catalogue, an international collabo-rative project studying humpback whale populations through identification of individual animals by naturalmarkings. The catalogue contains records of over 5,000 humpback whales collected over 25 years by over 350individuals and research groups. These data were compiled by Peter Stevick and are used courtesy of College ofthe Atlantic , Bar Harbor, Maine, USA.

Large-scale migratory movements

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Humpback Whale MigrationsHumpback Whale Migrations

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Distribution of lobster postlarvae:Relationships to coastal currents &effects on lobster population dynamics

After hatching, young lobsters spend about a month swimming in the plankton as they develop through fourdistinct stages.The last of these is called the postlarva, and in this final stage lobsters settle to the bottom. InMaine, postlarvae reach their peak abundance in late July to middle August. Lobster larvae and postlarvae aregood vertical swimmers, but their horizontal location is determined mostly by the strong tidal and sub-tidal (orresidual) currents in the Gulf of Maine.

The relationship between where larvae hatch and where they settle is complex, but understanding theunderlying processes (hatching distributions, swimming, feeding, mortality, transport) provides insights into pat-terns of lobster production and how (and why) these patterns might change over time. Because lobsters are animportant resource, it is easy to understand why this knowledge is important: one cannot judge the effects of fish-ing pressure and management actions unless one understands the underlying, natural forces that affect abundance.But knowledge of these processes also can be applied to other planktonic organisms (see the section on ParalyticShellfish Poisoning) or organisms with planktonic larvae.To be most effective, a census of marine life must com-bine discovery and the description of animal and plant distributions with an understanding of the processes thatcreate these patterns of distribution, abundance and diversity.

The accompanying figure is a snapshot of the distribution of lobster postlarvae in early August 2002, andrepresents a pattern we have seen in other years as well. Here, the abundance of postlarvae is far greater in the

Distribution of lobster postlarvae:Relationships to coastal currents &effects on lobster population dynamics

Lobster Larvae and Sea Surface Temperature,August 2001Lobster Larvae and Sea Surface Temperature,August 2001

warmer coastal surface waters south of Penobscot Bay than in the colder, mixed waters to the east.Why? One explanation is that the eastern coast of Maine is dominated by a strong coastal current that moves

from northeast to southwest, carrying larvae and postlarvae with it.That current is cold during summer becausestrong tidal currents in eastern Maine keep mixing the water column. Off Penobscot Bay, the eastern current joinsand abuts a weaker, western coastal current that is much warmer (less tidal mixing allows heat to accumulate inthe surface layer). Some of the eastern current turns offshore (see figure), some continues down the coastal shelf,and some enters Penobscot Bay.

How much does what, how variable is it, how does it affect lobster recruitment patterns, and what causes itto change? How much does eastern hatching contribute to western settlement? And what sustains settlement inthe east? The answers to these questions require many approaches, including ship-board research, ocean observ-ing buoys and circulation and biological modeling.These activities have many benefits besides just understandinglobster population dynamics; they contribute to human operations and management, as well as our understandingof other elements of the ecosystem.The ability to access and map such data enhances the speed of communica-tion and development of ideas about the Gulf of Maine as a system.

— Lewis Incze, University of Southern Maine

Lobster postlarval data came from Lew Incze, Nick Wolff (University of Southern Maine), Eric Annis (Universityof Maine) and Corrie Roberts (Island Institute); Sea surface temperature image is derived from NOAA AVHRRdata and provided by the Gulf of Maine Ocean Observing System (GoMOOS) and the University of Maine.

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Lobster Larvae and Sea Surface Temperature,August 2002Lobster Larvae and Sea Surface Temperature,August 2002

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Mapping the movements of egg-bearingfemale lobsters & bottom temperatures

The Lobster Conservancy and a group of lobstermen in Friendship, Maine, are tracking the movements ofegg-bearing female lobsters.The purpose of the Lobster Sonar Tracking Project is to investigate where and atwhat temperatures female lobsters spawn (egg out), carry (brood) and hatch their eggs (release larvae), and totest the Inshore Brood Stock Hypothesis.

Lobsters generally spawn during late summer; brood their eggs for 9 – 12 months; then hatch their eggs thefollowing spring and summer.The Inshore Brood Stock Hypothesis makes predictions about where spawning,brooding and hatching will occur and relates reproductive behavior to animal size and environmental variablessuch as temperature.The prevailing view is that female lobsters migrate to deeper, warmer water in winter toachieve a temperature advantage for incubating their eggs.Yet the study results presented here suggest that migra-tions between shallow and deep water explain only part of the story and that female lobsters that move to deep-er, warmer water do not necessarily brood their eggs for a shorter period of time. In addition, the female lobstersthat traveled the longest distances did not experience the warmest water temperatures.The biggest gaps inknowledge lie in where the females hatch their eggs — a critical piece of information for understanding larval dis-persal.

In the fall of 2002, approximately 200recently spawned female lobsters weretagged with an acoustic transmitter and anidentification tag. Lobster-men tracked thelobsters by detecting their locations usinga hydrophone and through recapture intraps.Tempera-ture data loggers wereattached to the lobsters to record hourlywater temperature throughout egg devel-opment.These data were recovered whenlobsters were recaptured in lobster trapsin spring and summer, 2003.

Preliminary results reveal thatapproximately one-third of the taggedfemales remained within two km of theoriginal capture location (coldest wintertemperatures), another third remainedwithin 30 km (warmest winter tempera-tures), and the remaining third traveleddistances up to 200 km (intermediate win-ter temperatures).

Three maps showing examples of thetemperature profiles and movements ofseven of the lobsters tracked inMuscongus Bay from September 2002through July 2003 are presented here.

Lobster #54 remained within one kmof her original capture location, the red“can” that marks the entrance to Morse’sChannel in Muscongus Bay. She wasdetected 14 times between September2002 and July 2003. Lobster #54 was firstcaptured and tagged September 18, 2002;its location was identified 12 additionaltimes via hydrophone detection, and finallyrecaptured by a lobsterman on July 11,2003 at which time her temperature datalogger was recovered (top map at left).

Mapping the movements of egg-bearingfemale lobsters & bottom temperatures

Lobster MovementsLobster Movements

SCUBA divers attempted torelocate Lobster #54 in April2003, but she apparently livedunder a large boulder and couldnot be seen.

In GIS mapping, a series ofcompromises and decisions aremade regarding which parame-ters to include on which map.The top map (left) shows theposition at which Lobster #54was detected on each date andthe color of the line of her tra-jectory indicates her thermalprofile.To achieve this represen-tation of the data, some informa-tion is lost because the twoparameters being mapped arerecorded on different temporalscales.Temperature was recordedhourly, while location wasrecorded on a daily or monthlybasis (except for two monthswhen ice cover prevented listen-ing in the channel). DuringFebruary, the temperaturerecordings fell below 0oC. Foralmost two months Lobster #54lived at temperatures at orbelow 0oC — yet, most of hereggs had already hatched whenshe was recaptured in July.Lobster eggs hatch a few hun-dred at a time and are releasedon a daily basis over a period ofweeks.Time of hatching wasdetermined by estimating thenumber of eggs and noting col-oration and condition of the eggsat the time of capture. Findingfew eggs on Lobster #54 in thehatching condition was surprisingbecause other lobsters that trav-eled to deeper, warmer watersand were at temperaturesbetween 4 o and 6oC during thesame time period did not hatchtheir eggs until August andSeptember.

Lobster #100 (bottom left)traveled to deeper, warmerwater. She was detected only sixtimes. Having fewer location datapoints exacerbated the problemof resolving hourly temperaturedata with sporadic positionaldata.Temperature data wereaveraged to allow for mapping.

The map at the beginning of

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Lobster Movement and TemperatureLobster Movement and Temperature

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28 this section shows location data for seven egg-bearing female lobsters — including lobster #54 (red line) and lob-ster #100 (yellow line) — that remained within the range of the researchers’ detection. Including several animalson one map made it possible to visualize general patterns of movement and to compare “movers” with “non-movers.”

However, much information was lost: because of the differences in location and degree of movement, it wasimpossible to include temperature information in this map. In addition, dates of detection would not be decipher-able at this scale.

The long-distance travelers (total displacement in one direction by approximately 200 km) presented a sepa-rate set of problems. In these cases, the location data are all outside of the range of detection by local lobster-men. Data include detections in and around Muscongus Bay and then recaptures in distant locations such asMassachusetts with a temporal gap of five to six months.

Overall, far more information could be gathered if the tracking devices could record depth, location andtemperature.A prototype transmitter that records depth is now available, and time-depth-recorders that collecttemperature data are commonly used on marine mammals, but such devices are too large for the lobsters tocarry and are extremely expensive.Transmitters for terrestrial animals and marine mammals (which come intocontact with air when they surface) can be tracked via satellite, but are very expensive. Information on lobstermovements could be improved if navigational buoys were equipped to receive depth, location and temperaturedata from lobsters and could relay this information to researchers via satellites.

Multiple recaptures of female lobsters reveal that they hatch their brood while they are traveling.This behav-ior results in broadcasting the lobster larvae over a broad geographic range — a dispersal strategy that avoidskeeping all of the eggs “in one basket.”

Covering all dispersal possibilities, the inshore broodstock lobsters appear to be engaging in at least threeseparate strategies that can be summarized as follows:

• Resident Broodstock spawn, brood and hatch the eggs in the same inshore location• Transient Broodstock spawn in shallow water near shore, brood in the closest available deep water, and

hatch while they are returning • Migrant Broodstock spawn inshore, travel great distances while brooding, then may or may not return

(they haven’t yet)

— Diane F. Cowan, The Lobster Conservancy

Sonar tag lobster data from The Lobster Conservancy.

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Northern shrimp:How maps tell two stories

Northern shrimp (pink shrimp or Pandulus borealis) inhabit various parts of the northernmost NorthAtlantic, North Pacific and Arctic Oceans.Their habitat characteristics include geologic properties of the oceanbottom (they prefer soft mud bottoms) and ocean temperatures (they prefer cold waters near the bottom).

In the Gulf of Maine, this cold-water species prefers the deepest and coldest waters in and around JeffreysBasin, and they can be found in depths ranging from 10 to 300 meters (5 to 150 fathoms).This is the southern-most and warmest limit of their preferred geographic range, which means that small changes in temperature (oneor two degrees Celsius) may make the difference between favorable and unfavorable habitat. Consequently, theseasonal and interannual variations in bottom temperature, which are often of this magnitude, influence shrimpabundance and distribution, and complicate management issues for this important commercial fishery.

These maps tell two stories about the biogeography of northern shrimp.The first relates to onshore–off-shore seasonal migrations, and the second relates to longer-term (interannual or multi-year) changes.With regardto the seasonal variations, the predictable migration and reproductive behaviors are almost surely related to tem-perature. In the summer, the sun heats a surface layer that varies in depth, but rarely extends more than a fewtens of meters below the sea surface. Consequently, during the summer, shallow regions near the coast and overthe major banks (Browns and Georges) tend to warm up, while deeper waters remain relatively isolated and cold.The typical summer condition is evident in the first map, showing the bottom temperature for July 2002. Someshallow coastal regions are more than five degrees warmer than the deeper waters in Jeffreys Basin.The 100-

Northern shrimp:How maps tell two stories

2002 State/Federal Shrimp Surveyand July BottomTemperature

2002 State/Federal Shrimp Surveyand July BottomTemperature

meter (50-fathom) depth contour, also known as “the edge,” depicts the transition between nearshore and off-shore in these maps.

Seasonal temperature changes impact life-cycle stages in northern shrimp. In late July, shrimp begin spawningin cold offshore waters (first map). Fall signals the onshore migration of egg-bearing females, apparently related tonearshore temperature change. From February to March, shrimp larvae hatch in inshore waters (second map),after which the adult females migrate back offshore into deep water before summer warming occurs. Juvenilesremain in nearshore waters for a year or more before they migrate to deeper water.

The shrimp data hint at the second story about the longer term, year-to-year changes in distribution.Thisstory is much more speculative. Filled circles in the maps represent the amount of shrimp caught for a given level

of fishing effort. Larger circles represent areas where shrimpare abundant and relatively easy to catch. Data from federalsummer surveys reflect the deep-water shrimp distributions(first map). Data from the winter fishing season emphasize theregions closer to shore, and come from port samples of land-ings from fishing vessels in Maine (second and third maps).

The two wintertime maps reveal a large interannualchange throughout the deepest parts of Jeffreys Basin occur-ring between February 2002 and February 2003.These bottomtemperature changes often arise from a very different mecha-nism than the seasonal changes discussed previously, and maysignal the arrival of cold water that has originated from verydistant regions, such as the Labrador Sea.

These data suggest geographic variation in shrimp stocks

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30 2002 Maine Fishery Port Sampling Dataand February BottomTemperature

2002 Maine Fishery Port Sampling Dataand February BottomTemperature

Michael Crocker, Northwest Atlantic Marine Aliance

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over time, but they say little about the reasons that abundance and distribution vary from one year to the next.Part of the uncertainty stems from the limited data on shrimp.These new types of biogeographic analyses simplyrequire more data. Further uncertainty comes from the simulations that generated the bottom temperatureimages in the maps.As in weather forecasting, accurate computer simulations of the ocean have huge datarequirements for “ground truthing.” Their accuracy improves when they assimilate continuous environmental datafrom observing systems such as the Gulf of Maine Ocean Observing System (GoMOOS). But GoMOOS andthese types of applications are still new.

A great deal of promise lies in the prospect of bringing these disparate fisheries and environmental datatogether with computer simulations, and to make that information available on a dynamic and ongoing basis.Themerging of data and computer models will enable researchers to begin the rigorous hypothesis-testing needed toexplain ecosystem dynamics in the Gulf of Maine. It will also provide an information base that allows resourcemanagers to begin implementing adaptive and ecosystem-based management practices, and it will help inform fish-ermen about the natural causes of changes in their fishery.

— Philip Bogden, Gulf of Maine Ocean Observing System

Maine fishery port sampling data was provided by the Maine Department of Marine Resources. State-federalsummer survey data was provided by NOAA’s Northeast Fisheries Science Center. Computer-model simulatedbottom temperatures provided by Huijie Xue, University of Maine School of Marine Sciences and GoMOOS.



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Selected readings on the distribution,movement and foraging patterns of northern right whales:Kenney, R. D., H. E.Winn, and M. C. Macaulay. 1995.Cetaceans in the Great South Channel, 1979-1989:right whale (Eubalaena glacialis). Continental ShelfResearch 15:385-414.Kraus, S. D., J. H. Prescott,A. R. Knowlton, and G. S.Stone. 1986. Migration and calving of right whales(Eublaena glacialis) in the western North Atlantic .Report of the International Whaling Commission SpecialIssue 10:139-144.Mayo, C.A., and M. K. Marx. 1990. Surface foragingbehaviour of the North Atlantic right whale, Eubalaenaglacialis, and associated zooplankton characteristics.Canadian Journal of Zoology 68:2214-2220.Stone, G. S., S. D. Kraus, J. H. Prescott, and K.W. Hazard.1988. Significant aggregations of the endangered rightwhale, Eubalaena glacialis, on the continental shelf of NovaScotia. Canadian Field-Naturalist 102:471-474.

Selected readings on movements and distribution of sand lance and humpbackwhales in relation to habitat:Nelson, G.A., and M. R. Ross, 1991: Biology and popula-tion changes in northern sand lance (Ammodytesdubius) from the Gulf of Maine to the Middle AtlanticBight. Journal of Northwest Atlantic Fisheries Science11:11-27.Nizinski, M. S., 2002: Sand Lance. Pages 495- in B. B.Collette, and G. Klein-MacPhee, editors. Bigelow andSchroeder’s Fishes of the Gulf of Maine. SmithsonianBooks,Washington, DC.Payne, P. M., J. R. Nicholas, L. O’Brien, and K. D. Powers,1986: Distribution of the humpback whale, Megapteranovaeangliae, on Georges Bank and in the Gulf ofMaine in relation to densities of the sand eel,Ammodytes americanus. Fishery Bulletin, US 84:271-277.Stevick, P.T., B. J. McConnell, and P. S. Hammond. 2002:Patterns of movement. Pages 185-216 in A. R. Hoelzel, edi-tor. Marine mammal biology: an evolutionary approach.Blackwell Science, Oxford.Weinrich, M., M. Martin, R. Griffiths, J. Bove, and M.Schilling. 1997: A shift in distribution of humpback whales,Megaptera novaeangliae, in response to prey in thesouthern Gulf of Maine. Fishery Bulletin, US 95:826-836.

Selected readings on right whales:Wynne, Kate, and Malia Schwartz; Illustrated by GarthMix. Guide to Marine Mammals and Turtles of the U. S.

Atlantic and Gulf of Mexico. Rhode Island Sea Grant,University of Rhode Island Narragansett Bay Campus.1999.Robert Bowman, Edward Lyman, David Mattila, CharlesMayo, Moira Brown. Habitat Management Lessons Froma Satellite-Tracked Right Whale. 2003. Center forCoastal Studies, Provincetown, Massachusetts and MountDesert, Maine. Presented to the ARGOS Animal TrackingSymposium March 24 – 26,Annapolis, MarylandAvailable online at http://www.coastalstudies.org/res-cue/BowmanARGOS.htmlMMPA BulletinAs part of NOAA Fisheries’ implementation of theMarine Mammal Protection Act (MMPA) Amendments of1994, the Office of Protected Resources (OPR) publish-es a periodic newsletter called the MMPA Bulletin.TheMMPA Bulletin provides information to the public aboutNOAA Fisheries actions and policies under the MMPA.Issue 22 features the story of Churchill. Current andpast issues are available electronically. Those and infor-mation about receiving print copies can be found at:http://www.nmfs.noaa.gov/prot_res/PR2/MMPA_Bulletin/mmpabulletin.htmlOr writing to:NOAA Fisheries Permits, Conservation and EducationDivision, Office of Protected Resources, 1315 East-WestHighway, Silver Spring, Maryland 20910 (301) [email protected]

Selected papers on humpback whale migration in the North Atlantic Ocean:Clapham, P. J. 1996. The social and reproductive biologyof humpback whales: an ecological perspective. MammalReview 26:27-49.Clapham, P. J., and J. G. Mead. 1999. Megaptera novaean-gliae. Mammalian Species 604:1-9.Katona, S. K., and J.A. Beard. 1990. Population size,migrations and feeding aggregations of the humpbackwhale (Megaptera novaeangliae) in the western NorthAtlantic Ocean. Report of the International WhalingCommission, Special Issue 12:295-305.Stevick, P.T., J.Allen, M. Bérubé, P. J. Clapham, S. K. Katona,F. Larsen, J. Lien, D. K. Mattila, P. J. Palsbøll, J. Robbins, J.Sigurjónsson,T. D. Smith, N. Øien, and P. S. Hammond.2003. Segregation of migration by feeding ground originin North Atlantic humpback whales (Megapteranovaeangliae). Journal of Zoology, London 259:231-237.Stone, G. S., S. K. Katona, and E. B.Tucker. 1987. History,migration and present status of humpback whalesMegaptera novaeangliae at Bermuda. BiologicalConservation 42:133-145.

Selected ReadingsSelected Readings

prototype biophysical maps of the gulf maine · having the data available and having them connected...

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