Abundance signals of amphibians and reptiles indicate strong edge effects in Neotropical fragmented forest landscapes. (August 2016)

• Record Type: Journal Article
• Authors: Schneider-Maunoury, Laure; Lefebvre, Veronique; Ewers, Robert M.; Medina-Rangel, Guido.F.; Peres, Carlos A.; Somarriba, Eduardo; Urbina-Cardona, Nicolás; Pfeifer, Marion
• Is Part Of: Biological conservation. Volume 200(2016)
• Page Start: 207
• Page End: 215
• Publication Date: 2016-08
• Subjects: Forest fragmentation -- Edge influence -- Species abundance -- Tropical forest -- Herpetofauna; Conservation of natural resources -- Periodicals; Nature conservation -- Periodicals; Ecology -- Periodicals; Environment -- Periodicals; Environmental Pollution -- Periodicals; Electronic journals; 333.9516
• DOI: 10.1016/j.biocon.2016.06.011
• Languages: English
• ISSNs: 0006-3207

Abstract

Abstract: Fragmentation and habitat loss contribute considerably to global declines of amphibians and reptiles. However, few studies focus on forest edges, created during the fragmentation process, as proximate drivers of the local demographic structure of populations. Here, we use abundance data of amphibians and reptiles to study their responses to forest edges in nine fragmented forested landscapes of the Neotropics. Species-specific abundance data were collected in plots established at varying distances from their respective nearest forest edge. We tested for edge effects on the abundance of species, and used curve clustering techniques to group species with similar edge responses, i.e. species with either increasing or decreasing abundance from the matrix towards the forest interior. We also grouped species that showed no change in abundance with respect to the nearest forest edge and those whose abundance response was unimodal, peaking in either forest habitat or the surrounding matrix habitat. We found that 96% of all amphibians and 90% of all reptiles showed an edge response, with the abundance of 74.5% of amphibians and 57.3% of reptiles decreasing with increasing proximity to forest edges. However, species-specific edge effects were not always consistent, with some species having opposite edge responses when measured in different landscapes. The depth of edge effects exhibited by forest species, i.e. species that increased in abundance in the forest interior, extended up to one kilometre away from forest edges. We show that the median edge effect on forest species extends to 250 m within the forest interior, indicating that tropical forest patches with a mean diameter < 500 m (minimum area ≈ 78 ha) are unsuitable for half of forest-dependent species considered in this study. Highlights: We analysed the response to forest edge of 43 amphibian and 61 reptile species. 93% of all species respond to forest edge, either decreasing or increasing in abundance. Edge effect can extend up to 250 m in the matrix and up to 2000 m into forest habitat. Models need to account for this edge effect: it reduces the area suitable for forest species.