Community structures of epibenthic macrofauna of three mangrove wetlands in Niger Delta, Nigeria: a comparison of community indices

Abstract

The epibenthic macrofaunal composition of three floristically different mangrove wetlands east of the Imo River, Nigeria, were investigated for the first time between December, 2000 and November, 2002. These resources of the swamps comprise a minimum of 11 families, 12 genera and 15 species at station 1 dominated by the native Rhizophora racemosa, Rhizophora mangle, Rhizophora harrisonii; 10 families, 11 genera and 14 species at station 2 with mixed mangrove macrophytes and 16 families, 18 genera and 23 species at station 3 dominated by the invasive palm, Nypa fruticans Wurmb. The result from station 3 is at variance with a non-empirical claim (widely held), that this Indo-Pacific mangrove palm has adversely affected these intertidal swamp fauna as it does the native mangrove macrophytes by eliminating them. The four diversity measures estimated gave disparate values and trends of diversity between the stations, but the index of Levin appears more sensitive and its assessment more reliable, upon which the three swamps are classified as oligodiverse and mesodiverse, with none being polydiverse.