cambodia marine conservation programme koh rong samloem… · 2017-06-30 · cambodia marine...

CMM 142 Science Report Jenn Reitz (Principle Investigator)

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CAMBODIA MARINE CONSERVATION

PROGRAMME

Koh Rong Samloem, Cambodia

CMM Phase 142 Science Report

1st April – 31

st June 2014

Jenn Reitz (Principle Investigator)


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Staff Members

Name Position

Jenn Reitz (JR) Principle Investigator

Gen Labram (GL) Assistant Research Officer


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Table of Contents

1. Introduction ........................................................................................................................... 4

2. Training ................................................................................................................................. 5

2.1. Briefing ................................................................................................................................ 5

2.2 Science lectures ..................................................................................................................... 5

2.3 Field work training ................................................................................................................ 6

3. Research Work Program ..................................................................................................... 7

3.1 Survey areas .......................................................................................................................... 7

3.2 Fish surveys .......................................................................................................................... 9

3.2.1 Introduction ........................................................................................................... 9

3.2.2 Methodology ......................................................................................................... 9

3.2.3 Results ................................................................................................................. 10

3.2.4 Discussion ........................................................................................................... 14

3.3 Coral cover and other substrates surveys ............................................................................ 15

3.3.1 Introduction ......................................................................................................... 15

3.3.2 Methodology ....................................................................................................... 15

3.3.3 Results ................................................................................................................. 17

3.3.4 Discussion ........................................................................................................... 18

3.4 Benthic invertebrate surveys ............................................................................................... 19

3.4.1 Introduction ......................................................................................................... 19

3.4.2 Methodology ....................................................................................................... 19

3.4.3 Results ................................................................................................................. 20

3.4.4 Discussion ........................................................................................................... 22

4. Proposed work program for next phase ........................................................................... 22

5. References ............................................................................................................................ 23


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1. Introduction

The Cambodian coastline, stretching 435 km along the Gulf of Thailand, is an especially productive

marine ecosystem owing to the influx of nutrients from five major river systems reducing the salinity of

the marine habitat (Touch, 1995). Thus far, 474 different species of fish from 105 different families have

been identified, as well as mammals (dolphins, dugongs), reptiles (sea snakes, sea turtles) cephalopods

(squid, octopus), crustaceans (crabs, shrimp, lobsters), molluscs (snails, sea slugs, bivalves), cnidarians

(jellyfish, coral, sea anemones) and echinoderms (star fish, sea urchins, sea cucumbers) among other

species which have not yet been recorded (Killeen, 2012).

Cambodia has 69 coastal islands. Coral reefs, sea grass beds and mangroves fringe many of these; all are

ecosystems that provide critical habitats for countless marine species. Coral reefs are one of the most

diverse ecosystems on the planet. Southeast Asia contains some of the most species-rich reefs on earth

and is home to the Coral Triangle; considered the epicenter of global marine biodiversity (Carpenter and

Springer, 2005). The main historical threats to coral reefs were storms and volcanic eruptions. More

recently however, anthropogenic pressures such as coastal development, overfishing and use of

destructive fishing methods, ocean acidification and pollution have proven to be incredibly detrimental to

the health of coral reefs. More than half of Southeast Asia’s reefs are classified as “high risk.” This has

primarily been caused by coastal development and fishing related pressures (Chou et al., 2002).

Increases in coastal tourism can have a detrimental impact on coastal ecology and reef ecosystems if not

properly managed (Hawkins and Roberts, 1994). Unregulated development can lead to substantial and

potentially irreversible environmental degradation; through the construction of resorts and associated

transportation infrastructure, overuse of water resources, increased fuel consumption and dumping of

sewage and litter (Davenport and Davenport, 2006). Cambodia’s minister of tourism, Thong Khon,

reports that tourism rates in Cambodia are increasing. In 2013, 4.2 million foreign tourists visited

Cambodia, an increase of 17.5% from the previous year (Cambodian Ministry of Tourism, 2013).

Published information about the current state of Cambodia’s reef systems is limited. Past studies have

produced estimates of the number of species that may inhabit the reef ecosystem, including hard and soft

corals, marine fish and molluscs. However, there are few studies of the reef’s current condition, thus

there is a need for additional studies to provide accurate data on the current status of these critical habitats

(Chou et al., 2002; Wilkinson and Souter, 2008).


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2. Training

2.1 Briefing Sessions

Briefing sessions are conducted with research assistants (RAs) upon arrival at camp (Table 1).

Table 1. Briefing sessions conducted during phase 142

Briefing session Presenter

Introduction to CMM project JR

Health and safety JR

Medical briefing JR

Camp life and duties JR

2.2 Science Lectures

After the initial briefing session, RAs were given science lectures covering the background and rationale

behind the Cambodia Beach Conservation project. Information relating to the different habitats and

species of Koh Rong Samloem, as well as current conservation issues in Cambodia was also provided

through a series of lectures (Table 2). The initial lectures included topics such as awareness of coastal

hazards, the types of marine habitats in Cambodia, the forms and function of the coral reef habitat and

reef fish morphology. Research assistants then proceeded to learn the reef fish that are surveyed using a

series of flash cards.

After successfully learning the fish species, RAs moved on to learning benthic substrate, invertebrate

species and survey methodology. A fifth lecture, ‘Coral cover, other substrates and survey methodology’

was presented at this time, followed by learning the types and classifications of substrates via flash cards.

The final component of the main training module was a lecture covering basic invertebrate types and

identification, combined with survey methodology and accompanied by a series of flash cards.

During phase 142, a lecture specific to coastal ecology and conservation in Cambodia was completed and

added to the basic training modules. There is also a series of lectures available for periods of inclement

weather when in-water work is not possible. These lectures include topics such as: mangroves, coral reefs

and climate change, marine pollution and Marine Protected Areas (MPAs).


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Table 2. Science lectures delivered during phase 142

Lecture Presenter

Coastal Hazards JR

Coastal Ecology and Conservation in

Cambodia

JR

Coral Reefs - Form and Function JR/GL

Reef Fish Morphology JR/GL

Coral cover, other substrates and survey

methodology

JR/GL

Benthic invertebrates and survey

methodology

JR/GL

2.3 Fieldwork Training

After the first four science training lectures (Table 2), RAs underwent a series of reef fish fieldwork

training tests before being allowed to survey. After passing a series of tests with flash cards, in-water

species tests were conducted. In order to pass the test, the most frequently seen species had to be

correctly identified three times each, before being allowed to survey. This test is administered on a one-

to-one basis as attempts in earlier phases with larger groups proved difficult. Following completion of the

in-water species identification test, an in-water size differentiation test was carried out. These tests ensure

that the RAs are able to accurately estimate reef fish size.

Following the training for reef fish surveys, benthic substrate composition and invertebrate identification

training sessions were carried out using a similar procedure. Practice surveys were conducted on the

beach and in-water to ensure RAs were fully familiar with the surveying methodology. During this time,

RAs also received training on any equipment they were unfamiliar with, such as how to use a compass or

transect line. Following successful completion of fieldwork training, RAs were ready to start collecting

survey data.


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3. Research Work Program

3.1 Survey areas

CMM is located in M’Pai Bai village on Koh Rong Samloem Island, which is situated approximately 23

km west of Sihnaoukville on the South Coast of Cambodia. There are currently two survey sites in the

waters surrounding M’Pai Bai (10°34′N 103°18′E). House Reef (Fig. 1), located on the east side of the

village, is a coral reef located within a proposed conservation area, currently in the planning stages

(personal communication, Coral Cay Conservation). Sunset Reef (Fig. 2), on the west side of the village,

is predominantly rocky with corals and other types of substrate scattered throughout. Between the two

reefs, there are currently a total of twelve active transect sites. However, tidal patterns at Sunset have

prohibited data collection for a large portion of phase 142. As a result, there is only sufficient data

available from House Reef’s transects for analysis this phase (Table 3).

Table 3. Transect locations and bearings in use at House Reef on Koh Rong Samloem.

Transect Reef Bearing (°)

Average

depth phase

141 (m)

Average depth

phase 142 (m)

Average

depth over

both phases

(m)

1 House Reef 50 2.56 2.20 2.40

2 House Reef 50 2.60 2.02 2.41

3 House Reef 50 2.02 1.82 1.93

4 House Reef 50 2.74 2.13 2.15

5 House Reef 140 2.31 2.13 2.24

6 House Reef 320 1.97 2.21 2.08

http://tools.wmflabs.org/geohack/geohack.php?pagename=Koh_Rong_Samloem&params=10_34_N_103_18_E_region:ID_type:isle


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Figure 1. House Reef on the east side of M’Pai Bai Village.

Figure 2. Sunset Reef, located on the west side of M’Pai Bai village.


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3.2 Fish surveys

3.2.1. Introduction

Reef fish diversity and abundance are important for supporting the ecosystems and communities on the

island of Koh Rong Samloem. Both are key components for maintaining proper ecosystem function and

in addition to their ecological importance, provide both a source of animal protein for the local population

and support a number of different livelihoods such as fishing, diving and tourism. Thus, the health of

coral reefs in the area is integral to the local economy, as most stakeholders rely on them in some capacity

as a source of income. Factors that may impact diversity and abundance include overfishing, storm

damage, terrestrial development, increasing sea-surface temperature, ocean acidification and sea level

rises (Cheal et al., 2002; Zhao et al., 2009). Spatial and temporal monitoring of reef fish will provide an

indication of the impact these disturbances are having on the reef. Effective monitoring efforts must be

long-term as certain species in the Pomacentridae and Chaetodontidae families can show a delayed

response to disturbance (Lewis, 1998).

3.2.2. Methodology

Underwater visual census adapted from reef check methodology (Reef Check, 2007) was used for data

collection. Transect sites were selected for surveying dependent upon visibility and tide levels. At each of

the survey sites, the abundance and size of 63 select families and species of fish were recorded. These

species have been selected based on ecological and commercial importance. Variables such as transect

number, sea state, cloud cover (percentage), tidal level and start time were recorded on entry into the

water. At the marker buoy of the specified transect, start depth was measured using a weighted measuring

tape. One surveyor subsequently set off on a predefined bearing, swimming slowly on that heading whilst

the second surveyor laid the tape out to a distance of 20 m. At 20 m, the team waited approximately two

minutes and then swam back along the length of the transect with one surveying 2.5 m left of the tape and

the other surveying 2.5 m right of the tape, both recording species abundance and size (Fig. 3). On

returning to the start of the transect, the team waited two further minutes and swam back along the length

of the transect, again recording species’ abundance and size as they went. This two-minute period allows

fish to return to their usual positions along the reef and mitigates the disturbance caused by the surveyors

themselves. At the end of the survey, one team member kept a visual reference of the transect end point

whilst the other reeled the tape in and returned to the end point. The end point water depth was then

measured and recorded; all data was then verified by field staff before entry into database.


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Figure 3. Baseline Survey Protocol (BSP) procedure for a 20 m transect. If any fish are seen within the

25 m2 box, they are recorded by the surveyor.

3.2.3 Results

Since the project began data collection at its present location on Koh Rong Samloem, 135 fish abundance

surveys have been carried out on House Reef and Sunset Rock Reef in total. Eighty-four surveys were

completed during phase 141 and 51 surveys occurred during phase 142. Due to extremely low water

levels over transect sites located on Sunset Rock Reef in the previous phase, there are insufficient

amounts of data for analysis from that site. During phase 141, higher species diversity was observed

during the surveys on House Reef compared to Sunset (Table 4). No fish species new to the area have

been observed during surveys this phase.

Table 4. Species observed during surveys on House Reef and at Sunset Reef.

Fish Species House Reef Sunset

Crescent Wrasse X X

Blue Streaked Cleaner

Wrasse X X

Tripletail Wrasse X

Chequerboard Wrasse X X

Freckled Grouper X

Bluelined Grouper X X


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Chocolate Grouper X X

Honeycomb Grouper X

Spotted Coral Grouper X

Longfin Grouper X X

Baramundi Grouper X

Peacock Grouper X

Starry Grouper X

Java Rabbitfish X X

Golden Rabbitfish X X

Virgate Rabbitfish X X

Indian Goatfish X

Freckled Goatfish X X

Eight Banded

Butterflyfish X X

Long Beak Coral Fish X

Blue-spotted Ribbon

Tail Ray X

Checked Snapper X X

Other Snapper Spp. X

Damselfish Spp. X X

Monacle Bream Spp. X X

Cardinalfish Spp. X X

Sweeper Spp. X X

Parrotfish Spp. X X

Fusilier Spp. X

Squirelfish Spp. X X


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Emperor Spp. X

Porcupine Spp. X

Puffer Spp. X

3.2.3.1 House Reef

As with the previous phase, the most frequently observed families on House Reef were Damselfish spp.,

Cardinalfish spp., and Butterflyfish spp. (Fig. 4). The mean abundance of Damselfish spp., Butterflyfish

spp. and Cardinal spp. remained relatively constant across the six transects. The mean abundance of other

species observed on House Reef was considerably lower (Fig. 5). Total mean abundance was fairly

consistent across transects at House Reef, with no significant differences (Fig. 6). This is in contrast with

results from the previous phase, which indicated that transect 4 had significantly lower total mean

abundance (296.7 ± 34.8 SE) than transects 3, 5, and 6 (Fig. 7).

Figure 4. Mean ± SE abundance of most commonly observed reef fish found at House Reef

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Butterflyfish Cardinal fish Damselfish

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Figure 5. Mean ± SE abundance of other reef fish found at House Reef

Figure 6. Mean ± SE abundance of reef fish found at transects on House Reef in phase 142

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Figure 7. Mean ± SE abundance of reef fish found at transects on House Reef in phase 141

3.2.4 Discussion

The data collected during this phase show many similarities to the results of the fish abundance and

diversity surveys conducted during the previous phase and in the project’s former location on Koh Smach.

Damselfish continue to be the most commonly observed species at survey sites on both Koh Smach and

Koh Rong Samloem. This may be partially explained by the sheer number of species included within the

Damselfish family. Other factors that may explain why they are observed with such frequency include

the availability of suitable habitats, food resources, breeding conditions and their size. Damselfish spp.

tend to be of a relatively small size and thus are less likely to be regarded as a suitable catch for local

fishermen. A 2003 study by De Lopez identified mullet, mackerel, snapper and sardines as the main catch

brought in by fishermen in the Ream National Park area, supporting this theory. High abundance of other

small species, such as Cardinalfish and Butterflyfish (Fig. 5), provides further support. Both snapper and

mullet spp. were surveyed at Koh Rong Samloem and their numbers were found to be low on both reefs.

During the previous phase, the total abundance of reef fish (regardless of species) showed some variation

between transects across the same reef (Fig. 7). This was initially attributed to changing habitats across

the reef; earlier studies have demonstrated that reef fish assemblages can change significantly across the

reef shelf (Williams, 1982) due to changes in habitat complexity and composition of the coral community

(Friedlander and Parish, 1998; Lewis, 1998). However, the results from this phase indicate no significant

differences between total mean abundance across transects on House Reef. The dissimilarities observed

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700

1 2 3 4 5 6

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Transect


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between phases are likely to be due to sampling effect as research activity in the area is still relatively

recent. Nevertheless, it is important to continually reassess whether there are significant differences in

fish abundance and assemblages and the conservation implications of this. In small areas with varying

fish assemblages, appropriate zone planning is often necessary (Jennings et al., 1994).

3.3. Coral cover and other substrate surveys

3.3.1. Introduction

In coral reef ecosystems, declining coral cover and condition has been linked to declines in fish

biodiversity (Jones et al., 2004; Wilson et al., 2006). Thus, it is important to survey coral and other

substrates to ascertain the overall health of a reef. Identifying coral to genus level is difficult and requires

a long period of training to acquire a high degree of accuracy. To address this issue, Frontier Cambodia

Marine has created key morphological categories to attain increased identification accuracy during

substrate surveys (Table 5). It is suggested that the three dimensional physical structure of the reef has a

bigger role in influencing reef fish assemblage than the overall health of the coral (Yahya et al., 2011).

Friedlander and Parish (1998) proposed that a more complex habitat may provide additional refuge from

predators and currents, as well as increasing the availability of resources. The key structural coral

categories created could be used as a proxy for coral reef complexity e.g. branching coral has a more

complex three-dimensional structure than massive coral.

3.3.2. Methodology

Coral and substrate surveys occurred along transects set up for surveying reef fish abundance (Table 3).

After completing the reef fish survey, five locations were randomly selected along each 20 m transect. A

50 by 50 cm quadrat was placed at each of these locations and used to assess the percentage cover for

each substrate category (Table 5). Any damage to coral in the form of bleaching, anchor damage or

disease was also recorded. If any dead coral was observed, it was recorded even if it was not possible to

ascertain causation. After completing each of the five sample quadrats, end depth was measured and end

time recorded.


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Table 5. Categories used to assess coral cover and substrate type on reefs surrounding Koh Rong Samloem

Category Other information to be recorded

Massive coral

Percentage cover of each coral

category present will be recorded.

If there is bleaching, damage to

coral or diseases (type) it will also

be recorded.

Sub-massive coral

Branching coral

Meandering coral

Plates of coral

Corals with daytime polyps

Corals forming columns

Solitary corals

Sea fan

Sea rod

Sea plume

Sponge

Coralline branching algae

Coralline encrusting algae

Macroalgae - Fleshy

Macroalgae - Filamentous

Sand

Bare rock

Rubble

Litter Type of litter will be recorded


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3.3.3 Results

Figure 8. Mean ± SE percentage cover of dominant substrates found at Transect 1-6 on House Reef during phase

142

Figure 9. Mean ± SE percentage cover of dominant substrates found at Transect 1-6 on House Reef during phase

141

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Consistent with observations made during phase 141, House Reef is dominated by filamentous algae;

massive and submassive coral, rock and sand (Fig. 8). Other coral structures, such as branching,

meandering, plate, daytime exposed polyps and solitary are present in lower frequencies and make up a

small proportion of the substrata. There were some differences identified between the data sets collected

from House Reef’s transects during phase 141 versus phase 142 (Fig. 8 and Fig. 9).

Table 6. Mean ± SE percentage cover massive corals and algae on House Reef transects

Massive coral Algae

Transect 1 (141) 16.12 (± 4.75 SE) 37.7 (± 5.53 SE)

Transect 2 (141) 41.4 (± 6.87 SE) 37.7 (± 6.23 SE)

Transect 3 (141) 43.84 (± 5.90 SE) 24 (±4.75 SE)

Transect 4 (141) 52.43 (± 6.83 SE) 27.1 (± 5.5 SE)

Transect 1 (142) 31.9 (± 1.02 SE); 30.3 (± 1.07 SE).

Transect 2 (142) 40.57 (± 5.82 SE) 33.8 (± 4.76 SE)

Transect 3 (142) 29.25 (± 5.5 SE); 20.9 (±3.43 SE).

Transect 4 (142) 43.65 (± 5.45 SE) 21.8 (± 3.86 SE).

During phase 141, transects 1-4 all showed increasing proportions of massive coral and similarly

decreasing proportions of filamentous algae and submassive coral (Fig. 9). Data collected during phase

142 follows similar patterns in respect to trends between categories, although individual transects show

variation between the two sets (Table 6).

The two most notable differences between the data sets are the decline in the percentage of rock observed

along transects and the presence of dead coral, previously undocumented on House Reef. Rock was only

found on transects 2 and 3 during phase 142, with mean percent substrate cover recorded at 1.33 (±1.33

SE) and 1.8 (±1.8 SE) respectively. Dead coral was observed in low frequency on all House Reef

transects except transect 2 where it was not observed at all. Transect 1; 2.67 (±1.0 SE), transect 3; 3.3

(±2.1 SE), transect 4; 1.13 (±0.94 SE), transect 5; 3.67 (±2.46 SE) and transect 6; 4.89 (±2.52 SE).

3.3.4 Discussion

While reef fish abundance and diversity are of primary importance to the stakeholders of Koh Rong

Samloem, it is important to assess coral cover and composition for a complete look at the status of a reef.

Coral cover and complexity are both factors that influence fish abundance. Studies demonstrating that


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there is a positive relationship between live coral cover and the total number of reef fish individuals (Bell

and Galzin, 1984; Feary et al., 2009) were supported by findings during phase 141; the site with higher

mean percentages of live coral cover also had higher mean total fish abundance. Reef complexity, or the

physical structure of the coral, also increases the biodiversity potential of the area through creating

ecological niches and is important to reef fish (Bell and Galzin, 1984; Friedlander and Parish, 1998;

Yahya et al., 2011), which was also in agreement with last phase’s findings.

Differences in substrate composition observed between the two phases include a decrease in the

percentage of rock along the transects and the occurrence of dead coral, which was previously not

observed during surveys. Again, these divergences are likely a result of sampling effect as this project is

still in the early phases of data collection. However, substrate surveys for the next phase will closely

monitor the frequency and proportion of dead coral on House Reef to verify whether or not it is

increasing, as it could indicate a serious problem for the condition of the reef. Cheal et al. (2002) state

that fish diversity gives a poor estimate of a reef’s resilience to a disturbance event, highlighting the need

to assess reef substrate composition in areas prone to disturbances. Given the current, rapid increases in

tourist development in the M’pai Bay area, it is essential that future monitoring covers both reef fish

assemblage and coral habitat.

3.4. Invertebrate surveys

3.4.1. Introduction

Invertebrate species are an important component of coral reef ecosystems and provide a wide variety of

ecosystem services. They are important grazers, filter feeders and predators within the reef community

and perform key services to reef systems in the form of nutrient recycling, water quality regulation and

herbivory (Przeslawski et al., 2008). In addition to fish and benthic substrate surveys, invertebrate

diversity and abundance surveys were conducted to sample the coral reef systems surrounding Koh Rong

Samloem as a whole. Invertebrates play an important role in reef health and due to their vulnerability to

climate change (Hutchings et al., 2007), it is important to obtain baseline data of invertebrates inhabiting

the reefs off Koh Rong Samloem.

3.4.2. Methodology

Transects set up for surveying reef fish abundance and benthic composition were also used to assess the

abundance of benthic invertebrates (Table 7). After completing the reef fish survey, but before measuring

the end depth of the transect, the abundance and diversity of invertebrates present were recorded. Five

stations were randomly selected along each 20 m transect. At each station a 50 by 50 cm quadrat was

placed. At each of these five stations, any benthic invertebrates present within the quadrat area were

recorded according to the categories shown in Table 7.


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Table 7. Categories of invertebrates surveyed during the fish and benthic composition surveys

Groups of invertebrates recorded in surveys

Worms Bivalves

Feather duster worm Tridacna spp.

Christmas tree worm Sea pen

Flatworm Cephalopods

Crustaceans Octopus

True crab Echinoderms

Shrimp spp. Chocolate drop starfish

Anemone shrimp Cushion star

Mantis shrimp Feather star

Hermit crabs Crown of thorns starfish

Gastropods Brittlestar

Topshell Collector urchin

Cowrie Pencil urchin

Conch Diadema spp.

Drupella spp. Holothuria spp.

Cone shell Synaptid spp.

Murex shell

Nudibranch spp.

Phyllidia spp.

Jorunna funebris

Glossodoris spp.

Phyllidiella spp.


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3.4.3. Results

Consistent with the last phase, the most common invertebrates on House Reef were clams; 2.93 (± 0.45

SE), Diadema; 0.94 (±0.23 SE), feather duster worms; 0.70 (± 0.2 SE) and Drupella 0.45 (± 0.2 SE).

Benthic species outside of these were rarely or never sighted.

Figure 10. Mean ± SE abundance of invertebrates found at House Reef.

Clams were the most common type of invertebrate found on House Reef. As seen below in Fig. 11,

transect 5 has the greatest number of clams (3.4 ± 0.52 SE) while transect 3 had significantly fewer clams

than any of the other transects (1.83± 0.41 SE). The distribution of the other types of common

invertebrates was mostly consistent across House Reef transects, with the exceptions of significantly more

Drupella observed on transect 2 (1.43± 0.05 SE) and significantly less Diadema observed on transect 3

(0.13± 0.24 SE). There was no significant difference between the number of feather duster worms on any

given transect.

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Figure 11. Mean ± SE abundance of common invertebrates found at House Reef.

3.4.4. Discussion

Clams have been the most commonly observed type of invertebrate on House Reef during both phase 141

and 142. Clams and other bivalves are filter feeders and play an important part in recycling nutrients

(Przeslawski et al., 2008). This is crucial for reef systems as they form in oligotrophic waters and need to

be very efficient in their use of nutrients (Jackson and Buss, 1975). Feather duster worms, another of the

commonly observed invertebrates, are also filter feeders and participate in this process as well. Personal

observations by staff and volunteers indicate that giant clams, sea pens and other bivalves have been

harvested and empty shells discarded onto the reef.

Growth of the tourism industry as well as an expanding local population may lead to increased bivalve

fishing, which would reduce the amount of filter feeding and exacerbate the nutrient load in the water.

Coupled with increased sewage outflow from wastewater sources, this could shift the current conditions

towards a system that has increased algal cover and thus, decreased coral cover. This would likely reduce

species diversity and may negatively impact fish abundance, as well as increase the reef’s vulnerability to

disturbances such as cyclones or sea surface temperature rises.

4. Proposed work programme for next phase

The proposed work programme for next phase includes a continuation of the current species surveys: fish,

coral and invertebrate surveys on House Reef and Sunset Rock Reef, with an emphasis on collecting data

from Sunset if tidal levels permit. Other potential survey sites will be investigated and integrated into the

program as appropriate. During the next phase a proposal to conduct socio-economic survey work will be

developed and, if approved, work will commence on developing a survey questionnaire to be put to the

local population.

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23

5. References

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