| Summary: | Maintenance and Update Frequency: notPlanned Statement: Statement: Site selection:Study areas were selected according to the following criteria:1. Proximity to the field station on Enderby Island2. Recent reports of abundant Acanthaster planci3. Results of previous surveysThe manta tow technique:An observer was towed at a speed of about 2 knots behind a dinghy around a portion of the perimeter of each reef. After each 2 minute tow period the following observations were recorded:1. The relative abundance of crown-of-thorns starfish. This is expressed as the total number of individuals observed, or according to one of 5 abundance categories:0 = 0 starfish1 = 1-9 starfish2 = 10-39 starfish3 = 40-100 starfish4 = greater than 100 starfish2. The relative abundance of distinct areas of recently dead (white) coral.This is expressed as the total number of coral scars observed. This provided an indication of the relative level of recent Acanthaster predation. 3. Estimates of the relative cover of live and dead hard corals.This is expressed according to one of 6 percentage categories:0 =0%1 =1-10%2 =1-30%3 =31-50%4 =51-75%5 =76-100% Credit Stoddart, James A, Dr (Principal Investigator) Surveys of crown-of-thorns starfish (Acanthaster planci) were undertaken in the western half of the Dampier Archipelago, at 3 fringing reefs (Enderby Island, Goodwin Island and Kendrew Island) and 1 barrier reef (Sailfish Reef) in 1987. The manta tow technique was used to record the relative abundance of crown-of-thorns starfish, numbers of white feeding scars on corals and estimates of live and dead hard coral cover. This technique was also used to identify suitable collection sites where Acanthaster planci was abundant.Samples of Acanthaster planci were collected using scuba at 2 sites on each of Kendrew and Enderby Reefs, and at 1 site on Goodwyn and Sailfish Reefs. Crown-of-thorns starfish were collected from each of these sites, except for Goodwyn Reef, where no individuals were observed.The diameter of each starfish was recorded ...
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