Dados do Trabalho

TÍTULO

ROAD-INDUCED EDGE EFFECTS ON BAT DIVERSITY AND ACTIVITY IN A NEOTROPICAL SAVANNA

Resumo

Roads cause direct and indirect effects on animals present in the surrounding habitat fragments. Because bats have extensive foraging ranges, they are particularly affected by roads, and their populations take longer to recover. This study aims to analyze road effects on bat activity and diversity, analyzed as species richness, in a Neotropical savanna and is the first to analyze road edge effects on bats in any Neotropical area. Near protected areas in Brasília, Brazil, we placed nine transects, and established sampling points at 0, 500, 1000, and 1500 m from the road. At each sampling point, we recorded bats for 12 hours using an ultrasound detector (Song Meter SM2). We used generalized linear models to evaluate the influence of season, road type, distance from road, distance from water, and artificial light on bat activity, species richness, and foraging effort. We identified 8,274 passes belonging to 35 species or species groups. The most abundant species were Myotis lavali and Lasiurus blossevillii. Activity and species richness were higher during the rainy season and higher near roads. Foraging effort was also higher in the rainy season but was related to distance from the road only for certain road types (higher further from four-lane highways) and in the presence of artificial light. Resource availability is lower in dry areas; thus, road verges can provide more feeding opportunities for bats as the artificial light lures insects. More resources in the area may also affect other insectivorous taxa, such as birds and other small mammals. Higher activity near roads increases the risk of collision with vehicles, therefore, we suggest that new road construction take bat commuting and foraging paths into consideration, adding structures to guarantee safe crossing when roads meet those paths.

Palavras-chave

Chiroptera, Highways, Insectivorous bats, Road ecology, Road verges, Urbanization.

Financiamento

The Rufford Foundation; CAPES; CNPq