Species Composition and Diversity of Insects of the Kogyae Strict Nature Reserve in Ghana

Abstract

Kogyae Strict Nature Reserve, the only one in Ghana, was established to promote scientific research, particularly on how nature revitalizes itself after major disasters, and also to check the southward drift of the savannah grassland. This study presents the first comprehensive inventory of species composition and diversity of insects of the Reserve. Insects were surveyed between September 2011 and June 2012 to capture the end of the rainy season, the dry season and the peak of the wet season. Samples were taken from two sites within the Reserve, Dagomba and Oku using various sampling techniques including pitfall traps, malaise traps and sweep nets. Insect communities were characterized in terms of, 1) species richness estimators, 2) species richness, 3) Shannon-Weiner Index of Diversity, 4) Pielou’s evenness and 5) Bray-Curtis similarity. A total of 8147 individuals representing 135 families from 21 orders were recorded. This included 107 species of butterflies from 9 families and 20 species of dragonflies from 3 families. Oku recorded the highest species numbers ( S = 63) and richness ( d = 12.16) with a high evenness of species ( J = 0.9377) during the peak of the wet season; and the lowest species numbers ( S = 58) and Margalef’s index of ( d = 10.14) in January. The highest Shannon diversity index of ( H = 3.927) was recorded at Dagomba in January.