Bat ecology and conservation in semi‐arid and arid landscapes: a global systematic review

Abstract

1. Semi-arid and arid landscapes (dry-lands) cover 41% of the Earth's land surface over five continents. These areas are home to 55% of mammal species. Bats have the second highest species richness among mammals, and, although many species are adapted to arid conditions, they are particularly sensitive in these habitats and require conservation priority. 2. Information on bats in arid and semi-arid landscapes is scattered, patchy and focused on small-scale studies; therefore, we undertook a systematic review using the PRISMA protocol to identify the current knowledge status, detect knowledge gaps and propose future research priorities. 3. We analysed 346 published articles and evaluated 40 topics within five topic categories (taxa studied, methodologies used, biology, ecology and conservation). The most commonly studied topic categories were ecology and biology. However, we found a gap in the topic category conservation (including topics such as conservation status and roost conservation). Our network analysis of topics within the categories showed that most ecology papers were focused on distribution, species richness and habitat use. 4. When we analysed keywords, we found that phylogeny, taxonomy and distribution demonstrated relatively high presence. Moreover, comparison of the percentage of studies conducted in dry-lands and the percentage of land surface area covered by dry-lands in the continents revealed that dry-lands in Africa and Australia were especially under-represented. Our review shows that knowledge of bats in semi-arid and arid landscapes is biased towards new records of the distribution of species, as well as covering systematic/ taxonomic and morphological aspects of bat biology.

Bats and wetlands: synthesising gaps in current knowledge and future opportunities for conservation

“…4a; see Appendix S1 for the full breakdown of topics assigned). Similar results were reported by Lisón et al (2019) in semi-arid and arid landscapes, where the majority of studies were focused on habitat use and species inventories. Most of the studies were strongly biased towards insectivorous bats and were performed in temperate areas (Fig.…”

“…2), probably due to financial limitations and ongoing social and political challenges (Racey 2013, Salvarina 2016. Lisón et al (2019) reported similar results, highlighting knowledge gaps in Africa, Asia, and Oceania with regard to bats in semi-arid and arid landscapes. For some countries (e.g.…”

“…All search results were screened, and information for the following fields was extracted from each study: 1) methodology; 2) country and continent where the study was performed; 3) main study topics; 4) sampling seasons; 5) bat assemblage, ensemble, guild or species; 6) International Union for Conservation of Nature (IUCN) Red List category for each species, when available; and 7) bat assemblage or species responses to wetlands, in terms of species richness, diversity or bat activity (responses were classified as positive, negative, neutral or not applicable, compared with other habitats). We also classified the topics covered in studies, based on the classification proposed by Tanalgo and Hughes (2018), with some extra categories extracted from Westgate et al (2015) and Lisón et al (2019; see Appendix S1 for the definition criteria). A single publication could contain a combination of different methodologies, countries, continents, topics, seasons, and target species, so each study was classified independently in more than one category and our sample unit is the study, not the publication.…”

Free-ranging livestock and a diverse landscape structure increase bat foraging in mountainous landscapes

“…Bats are in most cases species of conservation concern due to their sensitivity to habitat changes, which make them vulnerable to a wide range of threats (Frick et al 2019;Russo et al 2017a, b). Our results suggest that maintaining low-intensity traditional farming in mountainous areas provide an asset to foster bat presence by offering profitable foraging conditions in otherwise relatively unproductive habitats (Lison et al 2020), where interspecific competition among bat species in the same foraging guild is more likely to occur (Salinas-Ramos et al 2020). Consequently, free-ranging and traditionally managed livestock should be seen as another management variable for bat conservation, in return for a potential ecosystem service provided by bats as pest suppressors.…”

Audible bats provide opportunities for citizen scientists

“…Bats that call at low frequencies tend also to be fast, high-flying species, often of arid regions, that are not well surveyed using typical methods (Jones, 1999). For example, Lison et al (2019) advocated for more citizen science survey efforts to better populate distribution and abundance data sets of rare desert bats, and our study provides a way forward to help address this need. We recognize several ways to improve on our own study that will benefit others.…”