Meeting Abstract

P1.37  Sunday, Jan. 4  Feeding Behavior of Juvenile Diadema antillarum, the Long-Spined Black Sea Urchin RIVERA, G/J*; TURNER, T; WALTERS, L/J; University of the Virgin Islands; University of the Virgin Islands; University of Central Florida hebejebes25@yahoo.com

Diadema antillarum play an important role in the coral reef community as a keystone grazer. As such they eat algae which compete with coral for space on the reef. Their grazing maintains algal density to a low level allowing corals to flourish and facilitating the recruitment of new corals. However, in the early 1980s there was a Caribbean wide die-off of Diadema caused by a still unknown pathogen removing 99% of the population. This created the opportunity for macroalgal cover on reefs to increase. Thus, the return of Diadema to reefs is important, but the feeding preference of the juvenile urchin (< 2 cm) is uncertain. Recent availability of the juvenile urchin in Brewers Bay, St. Thomas, US Virgin Islands allowed for an assay to assess feeding preferences. Five trials were conducted, each with 30 juvenile urchins, and each urchin was fed a single algal thallus for five days. Trials tested: the red alga <i>Acanthophora spicifera , the brown algae Dictyota menstrualis and Lobophora variegata, the calcified green alga Halimeda opuntia, and the uncalcified green alga Caulerpa macrophysa. Juvenile urchins had distinct significantly different preferences (Kruskal-Wallis, p <0.001): they ate large amounts of <i>Acanthophora and Caulerpa but much less of the other species. This information may help managers wishing to return urchins to reefs. Funded by NIH MBRS-RISE Grant # GM6132, NSF HBCU-UP