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We evaluated Canada Warbler (Cardellina canadensis) responses to changes in habitat characteristics (landscape metrics, landcover, and microhabitat features) at multiple spatial scales resulting from timber harvests (clear-cut, heavy partial, and light partial) between 1996 and 2009. Relative abundance of Canada Warblers decreased over time on our West Virginia study area (Wildlife and Ecosystem Research Forest) and within the Appalachian Bird Conservation Region. Initially, relative abundance was greater closer to roads, but as timber harvests became more common, relative abundance became positively associated with amount of light partial harvests at the local scale. Nest survival was 45.6±18.3% during 1996–1998 and 24.9±14.6% during 2007–2009, but did not differ (P=0.38) between these periods. Areas around nests in 2007–2009 (n=17) had less intermediate canopy cover and fewer residual trees but more green cover, woody debris, and pole trees than areas around nests in 1996–1998 (n=10). Successful nests had more low cover, less vertical diversity, more woody debris, more saplings, and greater edge density than failed nests. We found a positive association between relative abundance and all three types of timber harvests and an improvement in habitat through understory development and retention of residual trees. Our research finds preliminary support for use of timber harvests, particularly light partial harvests, as a management tool for Canada Warblers in the southern portion of their range with the need for extended research using treatments and controls to confirm successful management.
