A survey of aquatic insects at Kware lake in Sokoto State

Abstract

A survey was conducted to determine the diversity and abundance of aquatic insects in Kware Lake, Kware local government area of Sokoto State from October to December, 2003. During these months, aquatic insects are associated mostly with permanent water bodies in Sokoto. Samples were obtained twice a week from the lake which was proportioned into three units, A,B and C. Morphological observations of the insect caught were carried out in the laboratory and five different species were identified viz, Calopteryx aequabilis (Say.) (damselfly), Haliplus solitarus (Sharp) (water beetle), Cordulegaster boltonii (Don.) (dragonfly), Libelullar quadrimaculata (Linn.) (dragonfly) and Coenagrion angulata (Hagen) (damselfly). The results indicated that dragonfly C. boltonii had the highest abundance with density of 45.0% while the water beetle; H. solitarus recorded the lowest abundance with density of 5.7%. Significant differences (P<0.05) in the mean count of the insect caught also exist among the species in the sampling units, which may be due to some environmental conditions like the vegetation covers or competitive exclusion might have set in.

Keywords: survey, aquatic insects, density, abundance, lake