Studies on influence of human activities on the species diversity of Odonata in parts of Lagos metropolis

Abstract

This study was conducted to determine dragonfly species diversity in a fish pond in Igbaga, Ikorodu (6.6671°N and 3.5983°E)and a large expanse of farm land in Ipaja (6.6044°N and 3.2660°E), southwestern Nigeria from January, 2016 to July, 2016 to as well as the effect of anthropogenic activities on the dragonflies at both sites. A total of 1002 dragonflies were collected belonging to20 species, 15 genera, and two families (Libellulidae and Aesnidae), were found at the two locations. The most dominant species in Site 1 (Ikorodu fish farm) was Chalcostephia flavifrons (36%) followed by Palpopleura lucia (15%) and the least were Palpopleura albifrons, Gynacantha nigeriensis, Diplacodes lefebvrii and Trithemis grouti which were one percent of the total numbers sampled. On the other hand, the most dominant species in Site 2 (Agricultural Farm in Ipaja) was Pantala flavescens (92%) and the least was Urothemis asignata (1%). Similarity test using Soerensen s quotient revealed a strong dissimilarity in the community structures of the two areas surveyed. The fish pond had a more even distribution of the dragonflies(e^H/S=0.508) and a higher concentration (H´=1.808) of dragonflies than Ipaja agricultural farm.