Understanding avian responses to forest boundaries: a case study with chickadee winter flocks.

Conclusions: Edge structure affects movement patterns in chickadee flocks. Flocks tend to move parallel to forest edges. Thresholds/Learnings: Synopsis: During a two-year study of chickadee flocks in a fragmented agricultural landscape near Edmonton, Alberta, researchers tested the degree to which flocks responded to forest boundaries based on changes in vegetation, foraging sites, and edge structure near these boundaries. The results indicate that sharp forest boundaries (edges) acted strongly as movement corridors for birds, encouraging flocks to move parallel (within 75 m) to forest edges.