Diversity pattern of bats (Mammalia: Chiroptera) in a modified tropical environment in the western region of Cameroon

Abstract

The western region of Cameroon is one of the leading agricultural production areas in sub-Saharan Africa, and this ongoing  anthropogenic perturbation has led to the replacement of natural forests with agroecosystems. Such anthropogenic landscape  transformations may have affected bat species composition and abundance in the area. Our study assessed the response of bat assemblages to these changes, by comparing species diversity and abundance across four distinct habitat types within the region: cultivated farms (transformed landscape), savannah and gallery forest (both representing degraded areas), and secondary forest. A total of 442 individuals assigned to 25 species were captured using ground-level mist nets. The cultivated farms recorded the highest bat species richness (13 species) and abundance (145 individuals), whereas the gallery forest had the lowest species richness (six species) and abundance (62 individuals). Myonycteris angolensis had the highest relative abundance in the region, with large numbers captured in cultivated farms. According to the rank-frequency diagram, bat assemblages in cultivated farms (Akaike’s Information Criterion (AIC) = 53.7), gallery forest (AIC = 27.7), and secondary forest (AIC = 48.5) are distributed according to the pre-emption model, whereas the distribution in the savannah (AIC = 40.0) follow the null model. Generalised linear models revealed significant differences in species and relative abundance across the four habitat types.

Keywords: agroecosystem, anthropogenic, null model, pre-emption model, rank-frequency