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 Blue-throated 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. © 2011 Springer Science+Business Media B.V.