Report on Reef Surveys carried out on the reef front
of Lawaki Beach Resort, Beqa,
by students from the Institute of Cultural Ecology, (I.C.E.)
Helen R Sykes
I.C.E. is a US based organization that arranges educational programmes for students, largely from the U.S.A. The students on this course were from a variety of universities in the U.S., and were an average age of 20-22 years old. They were trained in survey techniques, and their surveys were supervised by Helen Sykes of Resort Support, a Fiji Reef Check National Coordinator.
Survey Team members:
Regina Bresler, Laura Kealty, Jennifer Krolick, Ben Megna, Neomi Mustain, Andrea Podesta, Daniel Proctor, Sarah Pulitzer, Julie Siegfried, Lindsey Smith, Paul Tannenbaum, Danika Zupic.
Survey Team Leader:
Helen Sykes (Resort Support)
Lawaki Beach Resort is a small resort on the South Western coast of Beqa island and can accommodate 9 guests only. The owners are a Fijian/Swiss couple, Christine & Semisi ("Sam") Tawake-Bachofner.
Stakeholders on Beqa island have recently met to pass joint resolutions on marine protection and conservation on the island’s reefs, but there have yet has been very few or no studies done to acquire data on the reef in the area.
The twelve students from I.C.E. spent 4 days at Lawaki Beach Resort. During this time they undertook a Reef Check survey of the reef flat immediately outside the resort, and also carried out a Crown of Thorns count on the same reef stretch. It should be noted that this was a very basic study, carried out by volunteer student surveyors, but the data is presented as the first baseline survey to be done on this reef, and it is hoped that this may be of use to the local stakeholders.
Map showing location of Lawaki Beach Resort on Beqa Island
All surveys were carried out on the shallow reef top at high tide, with the surveyors using snorkel gear only. No deeper surveys were done at this stage.
Reef Check is a simple reef survey technique that is easy to learn and carry out. It records populations of standard fish and invertebrates, and measures the amount of live coral, rock, sponge, and other sea bed types along a belt 100 metres long by 5 metres wide. It can be used to provide a broad view of coral health, and changes such as coral death or re-growth can be recorded.
www.reefcheck.org for details of methods.
Crown of Thorns (COTs) are sea stars that eat the coral animals. In small numbers they are part of the natural population of the reef. In large numbers, they can destroy whole coral reefs. If there are more than 30 COTs seen on 1 hectare (100 metres by 100 metres of reef) it may be considered advisable to remove them as part of a coral protection plan. 5 students spent an hour counting and measuring COTS along the reef edge. The area covered was approximately 300 metres long by 10 metres wide (0.3 hectares).
Reef Checks were carried out on the reef flat within view of the deeper edge, but entirely on the shallow reef top. Two surveys were done. Both started opposite the creek mouth at the Northern edge of the resort property at GPS point 18o24.47'S 178o05.37'E.
One team surveyed 100 metres to the North of this point, the other team surveyed 100 metres to the South.
Crown of Thorns counts were carried out along the reef edge, concentrating on the deeper reef, but including the edge of shallow reef. The surveyors started in the vicinity of the boat mooring buoy and moved out to the farthest edge of the Reef Check area.
Sketch Map showing areas of surveys:
Reef Check Benthic Cover (Sea Bed Type)
In this survey 160 points along the 100 metre survey line are counted and the type of sea bed cover at each point is recorded. The types are:
· HC = Live Hard Coral of any kind
· SC = Live Soft Coral of any kind
· RKC = Recently Killed Coral: any coral which died in the last 12 months
· NIA = Nutrient Indicator Algae: seaweeds that show sewage or fertiliser in the water.
· SP = Sponge
· RC = Rock or large pieces of coral that have been dead longer than a year
· RB = Small pieces (less than 15 cm) of rock or long dead coral
· SD = Sand
· SI = Silt (fine river mud)
· OT = Other: any other kind of living sea bed cover.
Reef Check Fish Species
In this survey certain kinds of fish are counted that swim along the 100 metre survey line and 2.5 metres to either side of it.
The fish that are counted are:
· Barramundi Cod (not found in Fiji waters)
· Humphead Wrasse
· Bumphead parrotfish
· Any other Parrotfish (larger than 20cm)
· Moray Eel
Reef Check Invertebrate Animals
In this survey certain kinds of invertebrates are counted along the 100 metre survey line and 2.5 metres to either side of it.
The invertebrate animals that are counted are:
· Banded Coral Shrimp
· Diadema Black Spiky Sea Urchin
· Pencil Sea Urchin
· Sea Cucumbers
· Crown of Thorns Sea Star
· Giant Clam (Vasua)
· Triton’s Trumpet Shell (Davui)
· Tripnuestes Sea Urchin (Cawaki)
Crown of Thorns counts.
Five students searching the area for approximately one hour discovered a total of 4 large Crown of Thorns (between 32 and 35 cm across).
All of these were found on the deeper part of the reef (about 3 – 4 metres deep), on sand and rock substrate, although one was found on a Diploastrea boulder coral.
One smaller one (approx 12 cm across) was found on a small table Acropora coral on the reef flat. A few white patches known as COTS scars, where they have been feeding, were found.
The overall number of COTS seen was 5 individuals in 0.3 hectare which would give a density figure of 17 per hectare.
Discussion of results:
This is a shallow reef top that has been fished over a long period by village subsistence fishers. It is also in an area that suffered a lot of coral death in the coral bleaching event of the year 2000, due to extremely warm water conditions.
There is now a lot of new coral growth on the reef top. Most of this is of the Acropora family, small table, finger and branching corals. These are mostly less than 30 cm across and have probably grown since 2000. Some of these show recent death due to COTS feeding, some due to causes unknown, but in general they are in good health.
Semisi Tawake has started a small clam farm, where he has placed 27 Giant Clams (Vasua) which he gathered from other reef areas. These have been on the reef for the past 3 years and are now between 18 and 22 cm along their longest side. There are also several smaller clams seen elsewhere on the reef.
He has asked the villagers not to fish with the poison vine, Duva, and this has been observed for a year or so at this point.
Reef Check Benthic Cover (Sea Bed Type)
20% of the reef top is covered in live coral, mostly new colonies, the rest mainly rock, rubble or sand. Between 2 and 8% of the reef was recently killed coral. A further study showed that a small amount of this was COTS feeding scars, but most of it was dead tips with some algae growing on them. The reason for this is not obvious. It could be from local community fishers reef walking and touching the coral, from low tides exposing the coral tips, or other reasons not seen. At this point it is not a significant amount of coral death, but it would be worth checking on in future to see whether the percentage increases.
There is only between 2 and 4 % of Nutrient Indicator Algae, which suggests that the resort is not significantly polluting the area with sewage.
Overall this is a healthy reef top showing a lot of new coral growth.
Reef Check Fish Species
Very few fish of any size were seen on the reef top. Of the fish seen, butterflyfish were the most common, followed by parrotfish and a few small snappers. No grouper, sweetlips or large food fish species were recorded. As butterflyfish feed largely on live corals, their presence reflects the good health of the corals in the area.
This pattern is seen repeatedly on shallow reef tops in Fiji, and is probably related to local fishing practices.
Reef Check Invertebrate Animals
There were quite a few larger sea urchins, black spiky Diadema, pencil urchins and Tripneustes (Cawaki) were all seen. There were also quite a few sea cucumbers, although not ones of food or commercial importance. These animals are important to reef health as they eat the algae which might otherwise choke the corals, so it is a good sign to find them.
There were quite a few small Triton’s Trumpets (Davui) and Giant Clams (Vasua) found, and this was also considered to be a very good sign, as these animals are often removed entirely by village fishing. They are both very important to reef health, Davui are considered to be one of the main enemies of the COTs as they eat the adults, and Vasua may filter COTS larvae out of the sea when it is their breeding season.
No COTS were seen during the actual Reef Checks, but they were found outside the transects, and a few feeding scars were seen.
Crown of Thorns counts
17 COTs per hectare were found on the reef, and this is below the 30 per hectare figure that is used to define a “plague” outbreak. This amount of COTs may even be of benefit to the reef by weeding out some corals and allowing space for other species to live. It does not warrant a COTS removal programme at this time. However, the ones seen were of spawning size, and it is suggested that regular counts need to be done so that if the amount increases (if it doubles to around 10 along the reef edge area) a removal programme could be considered.
This reef area is generally healthy and has a good population of invertebrates and corals. It is low in fish counts due to local subsistence fishing. The operation of the resort does not appears to be harming the reef at this time, and indeed is benefiting it by protecting the reef from poison fishing and providing breeding grounds for Giant Clams.
It has a variety of habitats from reef top to deeper boulders and cuts, and would be a good candidate for conservation and protection programmes if such were required.
This is the first study in the area, and regular such studies once a year are recommended to record any changes in health.