A metabarcoding assessment of the diet of the insectivorous bats of Madeira Island, Macaronesia

Abstract

Understanding the trophic structure of species assemblages is crucial in order to comprehend how syntropic species coexist in space and time. Bats are the second most taxonomically diverse group of mammals and display a wide range of dietary strategies. Due to their ability to disperse over water, ca. 60% of all extant bat species occur on islands and for the most part their interspecific ecological interactions are poorly known. Using DNA metabarcoding, this study offers the first insights into the diet of Macaronesian bats by providing a holistic overview of prey consumed by all 3 bat species found on Madeira Island (Pipistrellus maderensis, Nyctalus leisleri verrucosus, and Plecotus austriacus) and investigating both interspecific (between P. maderensis and N. l. verrucosus) and intraspecific (between female and male N. l. verrucosus) dietary differences. We identified a total of 110 species of arthropod prey in the diet of the 3 bat species, including multiple agriculture and forestry pest species, a human disease-relevant species, and numerous taxa not previously recorded on the island. Lepidoptera was the primary prey order for all 3 bat species. The diet composition of P. maderensis and N. l. verrucosus differed significantly, with P. maderensis consuming more Diptera and multiple prey taxa not found in the diet of N. l. verucosus. Moreover, male N. l. verrucosus exhibited a broader niche breadth than females. This study is among the first to use DNA metabarcoding to evaluate the diet of insular bats and thus greatly advances knowledge regarding the trophic ecology and pest suppression services of these poorly-known mammals.

Diel activity of insectivorous bats in response to land-use change in São Tomé Island, Gulf of Guinea

“…However, we also noted differences in the number of species present. Bat species may be able to coexist sympatrically, without the need for temporal partitioning, where species exhibit substantially different prey preferences (Gonçalves et al 2024), or where the abundance of prey is su cient to support similar prey preferences without substantial interspeci c competition. Given differences in the morphology and echolocation between M. newtoni and Chaerephon spp.…”

“…Therefore, islands are important ecosystems for bats. Yet, despite the key ecological roles played by insular bats (e.g., seed dispersal and arthropod suppression; Florens et al 2017; Gonçalves et al 2024; Kemp et al 2019), they lag their mainland counterparts in terms of research attention (Conenna et al 2017). Fortunately, the increasing availability of affordable passive acoustic detectors now allows for more comprehensive island surveys of echolocating bats (e.g., Ferreira et al 2022;Nóbrega et al 2023), offering an opportunity to investigate how anthropogenic stressors impact insular bat communities more thoroughly.…”