Authors : I.K. Esenowo and A.A.A. Ugwumba
Abstract: A study on the composition and abundance of macrobenthos of Majidun river, Ikorodu, Lagos state was carried out from June, 2008 to May 2009 at 6 sampling stations along the river from its source to the mouth. The river is a multipurpose resource for artisanal fishing, transportation, sand mining and domestic uses. A total of 10,799 individuals of macrobenthos belonging to 18 genera in two Phyla, Mollusca and Anthropoda were recorded from the 6 sampling stations. Mollusca were represented by Bivalvia and Gastropoda, the most common species were the gastropods: Pachymelania aurita, P. fusca, P. fusca var. quadriserlata, Tympanotomus fuscatus var. radula, T. fuscatus fuscatus and Melanoides tuberculata. Arthropoda consisted mainly of caddis fly larva, Phryganea sp., the crabs: Sesarma huzardii, Cardisoma armatum and Callinectes latimanus and the prawn: Macrobrachium marobrachion. T. fuscatus var. radula was the most abundant species accounting for 20.17%, closely followed by P. aurita 19.58% while the least abundant, Phryganea sp., accounted for <0.1% of the total number of macrobenthos. Shannon-wiener diversity index indicated a maximum of 0.97 in mid river station (surrounded by mangrove trees) compared to the stations at the source of the river (0.88) and its mouth (0.87) where it flows into Lagos Lagoon. Macrobenthos abundance and diversity levels were significantly low.
I.K. Esenowo and A.A.A. Ugwumba, 2010. Composition and Abundance of Macrobenthos in Majidun River, Ikorordu Lagos State, Nigeria. Research Journal of Biological Sciences, 5: 556-560.