Multiple dimensions of biodiversity in paleotropical hotspots reveal comparable bat diversity

Abstract

Bat species commonly comprise at least 50% of tropical mammalian assemblages, but Afrotropical bat faunas have been little studied leading to perceptions that they are depauperate. Here, we compare alpha taxonomic, functional, and phylogenetic diversity of insectivorous bats belonging to the narrow-space foraging ensemble from a bat diversity hotspot in Nigeria to species-rich sites in Indonesia and Malaysia, using previously published data. The Nigerian site is protected unlogged forests at Afi Mountain Wildlife Sanctuary and Cross River National Park. For comparison, we targeted similar unlogged forest sites in Southeast Asia: Indonesia—Bukit Barisan Selatan National Park Forest in Sumatra; and Kakenauwe Forest Reserve on Buton Island, Sulawesi; and another in Malaysia—Krau Wildlife Reserve. All sites were sampled using comparable methods, with an emphasis on harp traps that effectively capture the forest-interior ensembles. We also compare regional beta diversity of bat assemblages in ecoregions using occurrence data (literature, unpublished records, and online natural history collections) from the Lower Guinean Forest and the Malay Peninsula. We demonstrate comparable alpha taxonomic, functional, and phylogenetic diversity of narrow-space bats among sites in Nigeria and Indonesia, but greater diversity in Malaysia. Turnover and overall beta diversity of bats among ecoregions was comparable between the Lower Guinean Forest and the Malay Peninsula, but nestedness was higher in the latter. Our results reiterate the value of harp traps in generating bat survey data that allows equatable comparisons of “mist net avoiders” in the Paleotropical forest understory. Our findings have implications for regional and local bat conservation.