Anthropogenic modulators of species–area relationships in Neotropical primates: a continental‐scale analysis of fragmented forest landscapes

Abstract

Aim We conducted the first comprehensive quantitative review on the effects of habitat fragmentation on Neotropical primates to examine how both patch disturbance and landscape variables modulate species-area relationships (SARs) and species persistence in fragmented forest landscapes.Location Neotropical forests, from Mexico to Argentina.Methods We use species occupancy data from 705 forest fragments and 55 adjacent continuous forests nested within 61 landscapes, which we compiled from 96 studies reporting data on patch-scale species composition and patch size/location. Presence-absence data on 19 species functional groups and an index of hunting pressure and matrix type were assigned to each forest patch. We adopted a multilevel analysis, examining SARs and patterns of species retention coupled with the additive effects of hunting pressure and landscape connectivity both across all forest patches and 728 sites nested within 38 landscapes containing four or more sites. ResultsWe uncovered a consistent effect of patch area in explaining primate species richness. Over and above area effects, however, SARs were strongly modulated by levels of hunting pressure at the landscape scale in predicting species occurrence and aggregate assemblage biomass. Matrix type was also a good predictor of both extant species richness and aggregate biomass when only non-hunted sites were considered, with patches in more permeable matrices containing more species.Main conclusions Although the importance of patch area in predicting species persistence is undeniable, we found that SARs were clearly affected by withinpatch human exploitation of increasingly isolated primate populations. Both expanding the number of forest reserves and enforcing protection within nominal protected areas are therefore required to ensure the long-term persistence of full primate assemblages. We highlight the importance of considering multiple anthropogenic effects in assessing the synergistic effects of land use to explain patterns of species persistence in fragmented tropical forest landscapes.

On the form of species–area relationships in habitat islands and true islands

“…For example: (1) variables other than area have been found to modulate the SAR (e.g. hunting pressure; Benchimol & Peres, ); (2) the ISAR is often unable to accurately predict the total richness of a set of isolates (Matthews et al ., Unpublished data); (3) and there may be interactions between the effects of decreasing patch area and increasing patch isolation (Hanski et al ., ). A further issue is that the majority of studies, including the present analysis, include all sampled species in SAR calculations.…”

Dung beetle persistence in human-modified landscapes: Combining indicator species with anthropogenic land use and fragmentation-related effects

“…With a high number of forest-dependent or forest-interior specialist species, dung beetle persistence in HMLs is highly affected by the presence of forest interior patches, even assuming that extirpation of specialists can be, to some extent, numerically compensated by disturbance-adapted species inhabiting peculiar assemblages across edge-affected or open habitats. Unfortunately, in the Atlantic Forest, nearly half of the remaining forest is located less than 100 m from open areas, over 70% is located less than 250 m from open land (Ribeiro et al, 2009) and most forest fragments are currently defaunated in terms of mammals (Benchimol and Peres, 2013). Further studies should examine dung beetle responses to disturbance across several ecological groups, including their ability to persist in edgeaffected habitats, since matrix specialists are likely to represent a small fraction of local fauna, particularly small-bodied species.…”

“…Particularly in the case of animals, discrepant abilities to persist in HML are related to (1) dispersal ability, particularly the ability to cross non-forested habitats (Schtickzelle and Baguette, 2003), (2) capacity of species to move in the matrix (Uezu et al, 2008), (3) use of edge-affected habitats (Banks-Leite et al, 2010), and (4) lack of collection or hunting by human-populations (Benchimol and Peres, 2013).…”

The use of species–area relationships to partition the effects of hunting and deforestation on bird extirpations in a fragmented landscape

“…Corlett, 2007;Abernethy et al, 2013;Benchimol & Peres, 2013), few have explored effects on birds and most of these on selected large species only (e.g. Bennett et al, 1997;Datta, 2009).…”