Fish communities in a tropical bay (Gazi Bay, Kenya): Seagrass beds vs. unvegetated areas

The fish fauna of seagrass beds and unvegetated areas in Gazi Bay (Kenya) was sampled in 9 stations with a beach seine. A total of 3601 fishes (>95% juveniles) was caught, comprising 75 species (40 families). The spatial patterns in the fish communities were investigated with multivariate statistical techniques. A first community occurred in the downstream part of a major river-fed creek and was characterised by a low density and diversity. These were sandy bottom stations with sparse seagrass vegetation. The dominant species of this community were Leiognathus elongatus and Bothus myriaster. A second community occurred in the upstream part of the same creek, and was characterised by a high density and diversity. Gerres acinaces and Atherinomorus duodecimalis were the dominant species. A third community occurred in the stations of the shallow part of the bay and was characterised by a high diversity but a lower density. The dominant species were Apogon thermalis and G. acinaces. Both latter communities occurred in stations with dense seagrass beds.