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In response to Edge's remarks on the movements of Poecile sp. in early winter: I have lived and birded in the contact zone where the ranges of Black-capped and Carolina Chickadees overlap--along the Missouri River in east-central Missouri since the 1960's. It has been my experience that out of place occurrences are most frequent in fall and winter, perhaps when these and other woodland birds form mixed foraging flocks and wander away from their regular environs. I suspect that the contact zone is 15+/- miles in width, perhaps narrower where the Mo. River is within it. I do bird more on the southern side of the zone so I have noticed the occurrence of black-capped more in areas where the Carolina is more predominant and this has almost always been in fall and winter. From personal experience it would be difficult for me to say which species might be expanding its range. The chickadee complex is an interesting group of birds with enigmatic behavior patterns and if you read Kroodsma's work, capable of forming enduring family enclaves within relatively small geographic areas. I also seem to recall that Dr. Bill Elder did some work with chickadees 30 or 40 years ago. Does anyone know if he published anything as a result? Don Hays _______________ Donald R. Hays Union, Missouri ------------------------------------------------------------ The Audubon Society of Missouri's Wild Bird Discussion Forum To unsubscribe or change subscription options: https://po.missouri.edu/cgi-bin/wa?SUBED1=mobirds-l&A=1