Habitat fragmentation drives inter-population variation in dispersal behavior in a Neotropical rainforest bird

Conservation ecology research, management and modeling often assume species-specific fixed traits ignoring intraspecific variation. Dispersal in animals is a heritable trait where intraspecific variation should be common, as it develops via interactions between landscape and behavioral processes. We conducted translocation-radio-tracking experiments and novel-environment tests on a Neotropical rain-forest bird (Pyriglena leucoptera, Thamnophillidae) to assess whether dispersal success and exploratory behavior are determined by an individual's population of origin (i.e. fragmented or continuous forest). Based on a model for non-optimal animal movement in human-modified landscapes, we predicted that individuals that evolve or develop in fragmented landscapes, with daily exposure to risky boundary and matrix conditions, would have higher resistance to boundary-crossing and overall increased dispersal success than individuals from continuous habitats. We found that birds from fragmented landscapes were more resistant to cross boundaries and more successful at crossing the matrix relative to birds from continuous forest. Novel-environment tests detected reduced exploratory scores for birds from fragments, suggesting they were slower-explorers, and possibly more thorough in assessing their environment which, in turn, may have enabled more successful matrix transit. Observed behavioral differences can emerge by genetic adaptation or behavioral adjustments. In any case, because P. leucoptera is capable of adaptive behavioral adjustments to fragmentation, gradual landscape changes should be encouraged to minimize the potential for emergence of non-optimal dispersal behaviors in human-modified landscapes. (C) 2017 Associacao Brasileira de Ciencia Ecologica e Conservacao. Published by Elsevier Editora Ltda.