Species diversity and distribution of dwarf crocodile (Osteolaemus tetraspis) in bushmeat markets in Benin metropolis, Edo State, Nigeria

This study investigated the diversity and distribution of dwarf crocodiles in eight bushmeat markets in Benin City, Edo State, Nigeria. The markets surveyed were New Benin, Oliha, Uselu, Oba Market, Ekiuwa, Ugbighokogho, Evbotubu, and Third Market between October 2022 and May 2023. A multi-method approach was employed, combining observation and measurement techniques. The Shannon-Wiener Index (H'), Simpson's Index (D), and Species Evenness (E) were calculated to determine the diversity and distribution of dwarf crocodiles. The results showed that Ekiuwa and Ugbighokogho markets had the highest Shannon-Wiener Index (H') values of 0.84 and 0.86, respectively, indicating higher species diversity. These markets also had the lowest Simpson's Index (D) values of 0.41 and 0.39, respectively, indicating lower species dominance. Additionally, Ekiuwa and Ugbighokogho markets had the highest Species Evenness (E) values of 0.92 and 0.94, respectively, indicating a more even distribution of individuals among species. However, when considering the monthly variation, Oliha, Ugbighokogho, and 3rd Market had the highest Shannon-Wiener Index (H') values of 1.05, 1.06, and 1.05, respectively, indicating higher species diversity. The results suggest that some markets have higher species diversity and evenness, indicating a more sustainable trade. The study recommends that conservation efforts focus on regulating the trade in dwarf crocodiles and promoting sustainable harvesting practices.

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