Rotifers of River Ethiope, Delta State, Nigeria

Abstract

The composition of rotifers with some physico-chemical parameters of River Ethiope, Delta State, Nigeria were assessed at five stations (Umuaja, Umutu, Abraka, Igun and Sapele) from February 2003 to January 2005 using standard methods. Fifteen species of rotifers identified represented a low rotifer composition dominated by Branchionidae constituting 28% species composition, Colurellidae (27%), Lecanidae 18%, Trichocercidae, Proalidae and Notomatidae had 9% each. Species richness was in this order; Station 3 >2>4>1=5 and abundance in Station 4 >3>2 = 4 > 1 order. High similarity index and Jacard coefficient were found between stations 4 and 5, 2 and 3, 2 and 5, 2 and 4 and lastly 3 and 5. The limnological parameters varied significantly within and among the stations except total dissolved solids, pH, dissolved oxygen and alkalinity (P