Black-capped Chickadee

A Black-capped Chickadee on 19 August 2019 at the Nisqually National Wildlife Refuge. I have been curious about this species’ migrations. Foote et al. (2010) write about what is currently known. Over 60,000 birds banded in Canada inicate that 90% of recaptured birds show no significant movements. Young birds (but few adults), apparently in response to seed cycles, irrupt from their nesting areas every two years or so. These irruptions can be aimless, but fall movements tend to be south and southwest and northeast in spring. Chickadees are reluctant to cross large bodies of water. In this situation, large numbers of chickadees can build up—36,000 chickadees were reported from the the shore of Lake Ontario. Perhaps this phobia explains why Black-capped Chickadees are common across most of northern North America but are not found on Vancouver Island, British Columbia.