Tropic attributes of the mudskipper, Periophthalmus barbarus (Gobiidae: Oxudercinae) in the mangrove swamps of Imo River estuary, Nigeria

Article type: Research Article

Authors: Udo, Mfon T.

Affiliations: Department of Fisheries and Aquaculture, Faculty of Agriculture, University of Uyo, Akwa Ibom State, Nigeria

Abstract: Aspects of the trophic attributes of the mudskipper, Periophthalmus barbarus, occurring in the mangrove swamps of ImoRiver estuary, Nigeria, were investigated during a 12-month period(April, 1992-March, 1993). Feeding intensity increased with size;it was higher in the dry season (November-April) than in the wetseason (May-October); monthly changes in the indices of feeding intensity were significantly correlated. Major food objects comprised detritus and benthic algae; crustaceans, insects,macrophyte matter and sand grains were minor food objects whilefish, molluscs, Chilopoda, nematodes and fungi were unconsciously devoured objects. Diet varied seasonally; algae and sesarmid crabs were generally more in the dry season than during the rains whereas FPOM and fish increased in the wet over dry season. The mudskipper display a high degree of euryphagy and can be considered as a generalist and an omnivore. The lower trophic status of P. barbarus qualifies it as a good aquaculture candidate. Food richness was higher in big-sized class (BSC) than small-sized class (SSC).Size-based and seasonal variations were not apparent in food richness. Diet breadth was higher in the BSC than the SSC; there was dry season increase in diet breadth.

Keywords: Periophthalmus barbarus, indices of feeding intensity, diet composition, mangrove swamp, Imo River estuary, Nigeria

Journal: Journal of Environmental Sciences, vol. 14, no. 4, pp. 508-517, 2002