Little information is available about the macrofauna of East African seagrassbeds. This study aims to contribute to the knowledge of this macrofauna. Seven stations were sampled in the seagrass beds of Gazi Bay (Kenya). Three of them are situated in the western and the side creek and include Cymodocea rotundata and C. serrulata. Three stations in the eastern creek include Thalassodendron ciliatum and one T. ciliatum station is situated in the bay. The benthos of the seagrass beds has also been studied. A distinction has been made between the leaves, stalks and roots. The faunal analysis shows the Crustacea to be dominant: Amphipoda, Isopoda, Tanaidacea, Cumacea, Copepoda, and Ostracoda are the most important taxa. The Decapoda are represented in very small numbers. The animals are, if possible, identified up to the genus-level and a morphological description is given. Their occurrence in Gazi Bay has been discussed. A key to the families and genera has been made. The structure of the macrofauna has been investigated by two multivariate analyses techniques, TWINSPAN and CCA. These analyses show a difference between the Cymodocea-community, the Thalassodendron ciliatum-community of the eastern creek, and the T. ciliatum-community of the bay. These three communities can also be divided in a leaf-, stalk-, and rootgroup. The eastern and western creek, following a vegetative study (1), are compared by means of the densities of their macrofauna. The densities of the epifauna of the western creek (1653 ind/m2) are much lower than in the eastern creek (21412 ind/m2). The densities of the benthos of the eastern creek (20085 ind/m2) are much lower than in the western creek (46337 ind/m2). An indirect assessment of the standing stock of the eastern creek gives a value between 0.02 and 166 9 DW/m2, that of the western creek between 0.0238 and 192 9 DW /m2.(1) P.H. VANAVESAATH, G. VAN DER VELDE and E. COPPPEJANS (1993).In : Dynamics and Assessment of Kenyan Mangrove Ecosystems, Final Report, A.F. Woitchik, ANCH, 35-55, Vrije Universiteit Brussel, Belgium. |