Habitat Preference and Distribution of Crickets (Orthoptera; Gryllidae) in Western Kenya

Abstract

Information for identifying biodiversity hotspots for species conservation involves the estimation of species abundance, distribution and habitat preference.  Adult crickets were sampled from four Agro ecological zones (AEZ) in Western Kenya during the months of June 2020 to January 2021 and identified morphologically.  Thirteen descriptive variables associated with topography, water, and greenness, were used to create a habitat distribution model.  Akaike information criteria (AIC) was applied to estimate the habitat preference for each cricket species.  A total of 3535 crickets were recovered, comprising 3335 insects belonging to 6 identified species and 200 others.  Gryllus bimaculatus had the highest relative abundance of 28.43% while Brachytrupes membranaceus recorded the least abundance of 4.67%.  The diversity indices showed that natural vegetation had the highest diversity index (H’= 0.361) and dorminance (D = 0.194).  Areas with human settlement had the least diversity index and dominance (H’= 0.231) and (d = 0.010) respectively.  The results indicate that the cricket species can be classified into three groups, Group I (Acheta domesticus, and Diestrammena asynamora) which preferred areas near settlement, Group II (Scapsipedus icipe, Gryllus bimaculatus, and Brachytrupes membranaceus) that preferred fields and grasses and Group III (Gryllotalpa africana) that preferred wet lands.  This study concludes that the most preferred habitats are natural vegetation, areas near water bodies, having high shelter density and away from human settlement.  Conservation management targeting habitats for this edible insect should form part of integrated species conservation measures focusing especially on the biodiversity hotspots.

Keywords: Abundance, Crickets, Diversity, Distribution, Habitat preference

DOI: 10.7176/JBAH/12-6-04

Publication date:March 31^st 2022