Marine algae of the Cayman Islands: a preliminary account

Abstract

Although the marine algal (seaweed) flora of the Caribbaean Sea is relatively well known, that of the Cayman Islands appears to have been only poorly described. A discrete marine algal checklist and flora of the island group is lacking although a few seaweeds are illustrated in Sefton. An important early source of information was the 'Oxford University Cayman Islands Biological Expedition' of 1938. The main collector was W. Kings. Their material was lodged at the Natural History Museum [BM] and the green and brown algae were determined by then staff member G. Tandy with some Enteromorpha spp. being determined by V.J. Chapman; Rhodophyta and Cyanophyta remain unidentified. Kings visited all three Cayman Islands in May and June of 1938; he collected at six sites on Grand Cayman, two in Little Cayman and at Stake Bay in Cayman Brac. There appears to be no published account of this expedition; a MS collection list has been compiled in the course of the present work. An important more recent source of data is the algal survey of Grand Cayman undertaken in 1974 and 1975 by G. Swain, formerly of Southampton University. Although there is no published paper on this work, a detailed MS list of species collected, and material, are held at BM. Precise locational information as grid references facilitated the preparation of a map of collecting sites. The detailed account of the Cayman Islands seashore vegetation by Sauer omits the algae despite appraisals of the mangrove community and brackish swamps. Potts investigated, for the first time, the biological zonation of rocky shores as part of a wider study of the ecology and geography of Little Cayman. Although Potts' account concentrated primarily on the fauna, a few algae were mentioned as occurring in rock-pools and on rocks at shallow sub-littoral levels. In the same study, Stoddart made no mention of algae despite investigating mangrove and other halophyte communities. Most recently, Johns & Moore investigated the contribution to the sea-floor sediment in lagoons and on reef terraces made by calcareous green algae of the genus Halimeda