Virgin Islands. A Rapid Assessment of Coral Reefs in the Virgin Islands (Part 1: Stony Corals and Algae)

Abstract

A ACT 'I'hc: Atlantic and Gulf Rapid Reef Assess~nent (AGRRA) benthos protocol was conducted in depths of 3-14 m at 32 coral rccf sites in the U.S. Virgin Islands (St. Crois, St. Thomas. St. John) and the British Virgin Islands (Ancgada. Guana Island and Virgin Gorda). Live stony coral cover averaged between 10% and 35% in 85% percent of the sites. The size of colonies 21-5 cnl in diameter aberagcd 55 c~n and their composition was dominated by the genus Mot~tasimea. Coral recruitment varied considerably among sites and was dominated by species that brood their larvae. Nearly all sites had stony corals that were affected by disease, bleaching or damaged by fish bites. Mean values for total (recent + old) partial mortality exceeded 40% of colony surfaces in eight sites and were between 20% and 40% for the remainder. The abundance of "standing dead" stony corals was typically less than I .5%. The relative abundance of macroalgae exceeded 30% in 15 o f 2 2 sites and macroalgae were dominated by Dictyota.