Townsend et al. • BICKNELL’S THRUSH IN WINTERING AREAS 
371 
recruitment rates for this species with first-winter 
birds comprising just 28 % of the sample. This 
might be expected in a single-brooded species that 
nests in a harsh climate with high rates of nest 
failure (Rimmer et al. 2001). 
Our results are preliminary, but they suggest 
several possibilities and future directions for 
research. Further studies are needed to examine 
the fitness consequences for Bicknell's Thrush 
wintering in dense understory, male-biased sites 
versus sites with an open understory, and equal 
sex ratios. Robust comparisons of habitat quality 
will require more detailed data on agonistic 
interactions, the role of body size variation in 
structuring habitat occupancy, food resource 
availability, levels of site fidelity, and annual 
survivorship at a range of overwinter sites. This 
information could clarify the role of habitat 
segregation in limiting female survivorship and 
help inform effective land conservation strategies 
for this rare. Globally Vulnerable species. 
ACKNOWLEDGMENTS 
We are grateful for funding support from the Association 
of Field Ornithologists. Carolyn Foundation. Charles Blake 
Fund of the Nuttall Ornithological Club. Conservation and 
Research Foundation. Eastern Bird Banding Association. 
Stewart Foundation. The Nature Conservancy. Thomas 
Marshall Foundation, U.S. Fish and Wildlife Service. 
L'SDA Forest Service Office of International Programs. 
William P. Wharton Trust, and the Wilson Ornithological 
Society. Permission to band and collect blood samples ot 
birds was provided by Ihc U.S. Geological Survey. 
Permission to conduct research in the Dominican Republic 
^as provided by the Subsecrctana de Areas Protcgidas y 
BiodiveTsidad, while authorization in Haiti was provided by 
die Ministry of the Environment and tlte Ministry of 
Agriculture, Natural Resources and Rural Development. 
Laboratory facilities and assistance were generously 
provided by I. J. Lovclte. We especially thank J. M. 
Almonte and E. G. Garrido I'or invaluable assistance in the 
field, and staff of the Socidte Audubon Haiti for logistical 
assistance in Haiti, Constructive reviews of this paper were 
provided by two anonymous reviewers. 
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