Avian Persistence in Fragmented Rainforest
Luc Lens,12*
Stefan Van Dongen,1
Ken Norris,3
Mwangi Githiru,24
Erik Matthysen1
What factors determine the persistence of species in
fragmented habitats? To address this question, we studied the relative impacts of forest deterioration and fragmentation on bird species in 12 rainforest fragments in Kenya, combining 6 years of individual capture-recapture data with measurements of current captures and museum
specimens. Species mobility, as estimated from species-specific dispersal rates, and tolerance to habitat deterioration, as estimated from change in fluctuating asymmetry with increasing habitat
disturbance, explained 88% of the variation in patch occupancy among
eight forest bird species. Occupancy increased with mobility and with tolerance to deterioration, where both variables contributed equally to
this relationship. We conclude that individual-level study, such as of
dispersal behavior and phenotypic development, can predict patterns of
persistence at the species level. More generally, for
conservation tactics to stand a high chance of success, they should
include action both within sites, to minimize habitat deterioration, and across landscapes, to maximize dispersal.
1 Department of Biology, University of Antwerp,
B-2610 Wilrijk, Belgium.
2 Department of
Ornithology, National Museums of Kenya, Post Office Box 40658, Nairobi,
Kenya.
3 School of Animal and Microbial Sciences,
University of Reading, Reading RG6 6AJ, UK.
4 Department of Zoology, University of Oxford,
Oxford OX1 3PS, UK.
*
To whom correspondence should be addressed. Present
address: Department of Biology, Laboratory of Terrestrial Ecology,
Ghent University, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium.
E-mail: luc.lens{at}rug.ac.be