Wednesday, July 2, 2008


A total of 220 photographs of the knobbly seastar (Protoreaster nodosus) were taken by the Star Trackers, Lin Juanhui and Lim Swee Cheng during six field trips to Cyrene Reef in May (8, 9 & 23) and June (6, 8 & 23) 2008.

Based on a recognition technique, these photographs belong to
186 individuals.

Measurements taken from 123 individuals showed that
45% of them are juveniles (seastar with minor radius less than 30 mm).

Adults were found in seagrass beds as well as sandy bottoms but juveniles were encountered only in
seagrass beds.

These results reaffirm the observation in 14 May 2008 that Cyrene Reef is an extremely important habitat for the locally endangered seastar. This is a large population, which is likely to contain a much larger number of individuals than the 186 recorded so far, as the reef is yet to be surveyed intensively. The high proportion of juveniles is also exceptional. There are at least seven populations in Singapore but none of them appears to be as sustainable as the one at Cyrene Reef. The seagrass bed seems to be especially important to the juveniles. This microhabitat probably serve as recruitment, feeding and refuge grounds for the seastars. The charming seastar and the ecologically important seagrass beds deserve more attention in research.

No comments: