Consequences of a large-scale fragmentation experiment for Neotropical bats: disentangling the relative importance of local and landscape-scale effects

Abstract

Context Habitat loss, fragmentation and degradation are widespread drivers of biodiversity decline. Understanding how habitat quality interacts with landscape context, and how they jointly affect species in human-modified landscapes, is of great importance for informing conservation and management. Objectives We used a whole-ecosystem manipulation experiment in the Brazilian Amazon to investigate the relative roles of local and landscape attributes in affecting bat assemblages at an interior-edge-matrix disturbance gradient. Methods We surveyed bats in 39 sites, comprising continuous forest, fragments, forest edges and intervening secondary regrowth. For each site, we assessed vegetation structure (local-scale variable) and, for five focal scales, quantified habitat amount and four landscape configuration metrics. Results Smaller fragments, edges and regrowth sites had fewer species and higher levels of dominance than continuous forest. Regardless of the landscape scale analysed, species richness and evenness were mostly related to the amount of forest cover. Vegetation structure and configurational metrics were important predictors of abundance, whereby the magnitude and direction of response to configurational metrics were scale-dependent. Responses were ensemble-specific with local-scale vegetation structure being more important for frugivorous than for gleaning animalivorous bats. Conclusions Our study indicates that scale-sensitive measures of landscape structure are needed for a more comprehensive understanding of the effects of fragmentation on tropical biota. Although forest fragments and regrowth habitats can be of conservation significance for tropical 3 bats our results further emphasize that primary forest is of irreplaceable value, underlining that their conservation can only be achieved by the preservation of large expanses of pristine habitat.

Response of primary and secondary rainforest flowers and fruits to a cyclone, and implications for plant‐servicing bats

“…Our results help to explain reports of little difference in animal abundance, but reduced richness in SF systems compared with PF ones elsewhere (e.g. for amphibians and lizards: Gardner et al., ; neotropical bats: Rocha et al., ).…”

“…SF can have important roles in sustaining fauna (e.g. Gascon et al., ; McConkey, Drake, Franklin, & Tonga, ; Scanlon, Petit, & Bottroff, ; de Solar et al., ; Sayer, Bullock, & Martin, ; reviewed by Dunn, ), but the ability to exploit these habitats varies among taxa (Barlow et al., ; Rocha et al., ). The consequence of a widespread shift from PF to SF on resources for servicing fauna (here pollinators and seed dispersers) in cyclone‐prone systems is poorly known.…”

The understory bat community in a fragmented landscape in the lowlands of the Los Tuxtlas, Veracruz, Mexico

“…Although PAFFASIT is of moderate size, it is apparently not large enough to sustain these species. One possibility is that there is a deficiency of certain functional traits that are needed in order to fulfill the resource requirements of certain species, for example, the diversity of potential prey (Rocha et al 2016). One other reason could be that the use of mist nets as the only sampling technique could be a limiting factor in the number of bat species documented at the PAFFASIT site.…”

Subtle changes in elevation shift bat‐assemblage structure in Central Amazonia

“…, Bobrowiec & Tavares , Rocha et al . ). Frugivorous and nectarivorous bats are directly influenced by the diversity of plants because of constraints related to the availability of fruits and flowers (Marques et al .…”

“…, Rocha et al . ). Bats respond to altitudinal gradients (Bobrowiec & Tavares ), climate (Estrada‐Villegas et al .…”