DENSITIES AND DIVERSITY OF GYMNAMOEBAE IN RELATION TO SOME INSHORE AQUATIC HABITATS AT BERMUDA

Densities and diversity of gymnamoebae are reported for three sites at Bermuda. Two are marine sites in Mullet Bay, and the third is a shall ow pond (Ferry Reach Park), Bermuda. Site 1 (edge of a small island in Mullet Bay) had higher densities of gymnamoebae (28,761/g sediment) t han at a disturbed site 2 (17,597/g), a boat mooring. The diversity wa s higher, however, at site 2 (H = 4.3) compared to site 1 (H = 3.3). T he site 2 species were larger including morphotypes categorized as typ e 1 (e.g. Mayorella and a reticulate amoeba). The brackish inland pond had higher abundances in the sediments (40,590/g) compared to the mar ine habitats. However, the diversity was lower (H = 2.7) and it was do minated largely by Vannella and Platyamoeba (categorized as morphotype 4). These data are consistent with findings at continental coastal lo cations in northeastern USA. Pond sediments generally contain higher d ensities of gymnamoebae than marine coastal sediments with less organi c content. The ratio of type 4 to type 1 amoebae in pond samples is hi gher than those from coastal sites. The data from Bermuda, an open oce an insular site, provide additional zoogeographic evidence for the gen erality of these patterns of abundance.