Assessment of Bat Colony Populations as Agricultural Pest Controllers in Kebbi State, North West Nigeria

This study assesses the population sizes and pest suppression services of insectivorous bat colonies in Kebbi State, located in Nigeria's North West geopolitical zone. Insectivorous bats provide economically significant pest regulation services to agriculture, but their populations are declining across West Africa due to roost disturbance and pesticide exposure. An emergence count survey was conducted at 18 bat roost sites including bridge culverts, tree hollows, buildings, and cave overhangs across Argungu, Birnin Kebbi, and Jega local government areas. Population estimates were derived using video frame counting. Diet composition was characterised by DNA barcoding of faecal pellets collected beneath roosts. An economic valuation of pest suppression services was estimated based on feeding rate models and insect pest composition in diets. A total of 12 bat species were identified across the 18 roost sites. The largest colony, a mixed-species aggregation of approximately 22,000 individuals in a bridge culvert in Birnin Kebbi, was estimated to consume approximately 90 kg of insects per night. DNA barcoding of faecal pellets confirmed that 34 percent of prey items matched insect pest species of maize and sorghum. Conservative economic estimates suggested pest regulation services valued at 18 to 32 million naira annually within the study area. The study recommends legal protection of roost sites under the Kebbi State Environmental Law and establishment of farmer-bat coexistence guidelines. Keywords: insectivorous bats, pest control ecosystem services, Kebbi State, bat colonies, economic valuation.