Distribution and habitat selection of Bicknell's thrush (catharus bicknelli) in the Catskill Mountains of New York State

Pierce-Berrin, Cheryl
Jon Atwood, PhD
Department of Environmental Studies
Presence/absence data for Bicknell's Thrush (Catharus bicknelli) was collected during the summer field season of 1999 and 2000 in the Catskills Mountains of New York State. Currently, limited data is available regarding Bicknell's Thrush distribution and habitat selection in the Catskills. This study uses playback of Bicknell's Thrush vocalizations to elicit responses on 24 high elevation peaks (elevations > 1067 m). These presence/absence data, coupled with vegetation characteristics described at each survey point, provides the basis to create a model showing the distribution of this species within the Catskill Mountains. Bicknell's Thrush were detected on 63% (n=16) of the surveyed peaks. Using a logistic regression model, percent cover of balsam fir in the sub-canopy can be used as the best predictor of Bicknell's Thrush presence in the Catskills. Further monitoring for this species on 11 other unsurveyed high elevation peaks in the Catskills should take place for greater understanding of Bicknell's Thrush distribution in the Catskill Mountains.

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