Crown-of-thorns starfish (Acanthaster planci) and coral cover surveys of the reefs of Vanuatu

Brief description

The distribution and abundance of the crown-of-thorns starfish (Acanthaster planci) and the cover of living and dead coral were investigated at 29 sites around 13 islands of Vanuatu using spot dives, manta tows and belt transects in 1988.Survey sites were located in the vicinity of the following islands and reefs: Aneityum, Tanna, Erromango, Efate, Cook's Reef, Pentecost, Gaua, Ureparapara, Reef Islands, Espiritu Santo, Malakula and Epi.Rapid macroscale surveys of the upper reef slopes (At each site, the number of Acanthaster planci observed was recorded. The percentage cover of living and dead scleractinian corals was visually estimated, and depth, aspect and coral diversity noted. Particular note was made of any extensive areas of dead standing tabulate and staghorn Acropora spp. on reef slopes as these indicated possible outbreaks of Acanthaster planci in the recent past.Additional details of Acanthaster planci activity on Efate reefs were obtained from questionnaires and interviews with tourist operators and divers. This research was undertaken to investigate the status of Acanthaster planci in Vanuatu. This research was a component of a survey of Vanuatu Marine Resources conducted in March/April 1988 and was funded by the Australian International Development Assistance Bureau.The objectives of the survey were1. To survey and describe the shallow water reef habitats from selected islands of Vanuatu, adequately covering geographical and environmental variation2. To survey and describe the marine habitats around the shores of Malakula, including offshore islands3. To derive a coastal management plan for Malakula and offshore islands which can serve as a basis for Coastal Zone Management plans for the rest of the country4. To train Ni-Vanuatu personnel in marine survey and marine conservation methods

Lineage

Maintenance and Update Frequency: notPlanned

Statement: Statement: Manta Tow and Spot Dives:Manta tow surveys were conducted for two minutes with the observer being towed behind a boat at approximately 2 knots as described in AIMS (1985). Spot dives were conducted on snorkel or SCUBA for a period of 20 minutes.About 150-200m was covered in each 2 minute tow or 20 minute swim (spot dive) and a swathe of 3-6m width of reef, depending on topography and visibility, was examined. The total area covered was between 600-1200 sq m; for convenience it is assumed that each observation covered an area of 1000 sq m.Belt Transects:Five random 50m transects were laid down at each site and all Acanthaster planci within 2.5m either side of the transect line were noted as described by Ayling and Ayling (1986).AIMS (1985) An assessment of the distribution and effects of Acanthaster planci (L.) on the Great Barrier Reef 1. Methods. Australian Institute of Marine Science, Townsville, Australia.Ayling, AM and Ayling, AL (1986) A biological survey of selected reefs in the Capricorn Section of the Great Barrier Reef Marine Park. Unpubl. Report to the Great Barrier Reef Marine Park Authority.

Notes

Credit
Done, Terence J (Terry), Dr (Principal Investigator)