B.J Oribhabor - Department of Fisheries and Aquaculture, Faculty of Agriculture, University of Uyo, P.M.B. ۱۰۱۷, Uyo, Akwa Ibom State, Nigeria
A.E Asuquo - Department of Fisheries and Aquaculture, Faculty of Agriculture, University of Uyo, P.M.B. ۱۰۱۷, Uyo, Akwa Ibom State, Nigeria
A.O Ekwu - Department of Fisheries and Aquaculture, Faculty of Agriculture, University of Uyo, P.M.B. ۱۰۱۷, Uyo, Akwa Ibom State, Nigeria

The acute toxicity of Nigeria Bonny light crude oil against hermit crab, Cliabanarius africanus of a tidal creek, Eastern Obolo, Akwa Ibom State, Nigeria was investigated in the laboratory under static bioassay. The test crude oil was found to be poorly toxic to the test organism, resulting in delayed mortality and consequent extension of the bioassay to 8 days. Based on the LC50, the toxicity of the test compound was more manifested on the 8 day than at 96 hour, with a toxicity factor showing that the test compound was approximately 12 times, more manifested against C. africanus on the 8 day than at 96 hour. Paired t-test showed that there was no significant difference between 96h LC50 (549.9 ml l1) and 8d LC50 (45.2 ml l1). The results of this study indicated that C. africanus is not a good early warning indicator for oil pollution but its response during spills could serve as a good indicator of adverse impact.

Acute toxicity, Bonny light crude oil, Cliabanarius africanus, Tidal creek, Nigeria