The value of fruit security for the conservation of a neotropical frugivore in human-dominated landscapes

Abstract

Understanding which habitat elements are critical for species' persistence in the human-dominated landscape is a fundamental challenge of conservation biology. In human-altered lands fruit can be less reliably available compared to intact forest, but it is unclear whether this affects generalist frugivores, the primary providers of the important ecosystem service of seed dispersal. Does the habitat element of fruit constancy influence the persistence of these species in human-altered lands? Radio-telemetry, foraging patterns and species incidence frequencies of a representative generalist frugivore, the Bluethroated Toucanet (Aulacorhynchus caeruleogularis) were used to examine the effect of fruit security, measured by a site's annual constancy of fruit energy availability (FEA). Toucanets were detected 20-30% more often in shade-grown coffee plantations with high fruit security (\40% of months with \1000 fruit calories). Despite the large size of this generalist frugivore, home range size was\2 ha, when estimated by the a-LoCoH method, regardless of whether the initial capture site was forest, coffee plantation with high fruit security or coffee plantation with low fruit security. However, home range size was larger for birds captured in low fruit security coffee plantations. Furthermore, birds captured in low fruit security coffee plantations spent more time in forest patches and windbreaks, while birds captured in high fruit security coffee plantations spent more time in coffee shade trees. The results of this study emphasize the important role that a tree species' contribution to annual FEA should be given in conservation applications within the tropical regions.

Canopy bird assemblages are less influenced by habitat age and isolation than understory bird assemblages in Neotropical secondary forest

“…However, Neotropical birds are an enormously diverse group, so secondary forest colonization rates are likely to vary greatly among different bird species and between the assemblages in different forest strata (Laurance et al., ). In contrast to understory species, many canopy species are able to disperse across open areas (Burney & Brumfield, ; Graham, ; Graham & Blake, ; Peters & Nibbelink, ) and hence reassembly might be faster in the canopy compared to the understory in isolated forests. Alternatively, reassembly in the canopy may be limited because many canopy species require an advanced level of structural complexity or resource availability before they can inhabit an area (Nadkarni, ; Nadkarni & Matelson, ).…”

From steps to home range formation: species‐specific movement upscaling among sympatric ungulates

“…). We used MCP instead of kernel estimators because the former performs better at low sample sizes, such as in the case of our daily ranges (Sharp ; Peters & Nibbelink ). Range area calculations were performed in the program R (version 2.11.1; R Development Core Team ) using package ‘Adehabitat’ (Calenge ).…”

“…Some studies have shown that sampling regime might be even more important than sample size in affecting range area estimates (B€ orger et al 2006). We used MCP instead of kernel estimators because the former performs better at low sample sizes, such as in the case of our daily ranges (Sharp 2009;Peters & Nibbelink 2011). Range area calculations were performed in the program R (version 2.11.1; R Development Core Team 2010) using package 'Adehabitat' (Calenge 2006).…”

Complex Ecological Interactions in the Coffee Agroecosystem

“…Several studies have reviewed the impacts of coffee intensification on bird abundance, richness, and community composition (e.g., Greenberg et al 1997a,b;Johnson 2000;Roberts et al 2000;Perfecto et al 2003;Komar 2006;Philpott et al 2008). Many have documented changes in resource use, foraging behavior, and roost selection based on differences in availability and stability of fruit and floral resources (Carlo et al 2004, Peters & Nibbelink 2011, Bakermans et al 2012, epiphytes (Cruz-Angón et al 2008), and distance to forest fragments (Luck & Daily 2003, Jirinec et al 2011). Coffee farms have been used as laboratories for understanding how sex and age influence bird foraging behavior ( Jones et al 2000) and how foraging strata influence infestation of birds by mite parasites (Dietsch 2008).…”