An extensive project (my MS Thesis) to map the ranges of Black-capped and Carolina Chickadees and their hybrids over the full extent of the the former's range in North Carolina. Method was by mapping their calls (the "chick-a-dee-dee-dee") and songs. At that time, Black-capped Chickadees occurred ONLY in the Great Smokies, the Plott Balsams and Richland Balsams. In the Smokies, there was no overlap in populations during the breeding se...
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An extensive project (my MS Thesis) to map the ranges of Black-capped and Carolina Chickadees and their hybrids over the full extent of the the former's range in North Carolina. Method was by mapping their calls (the "chick-a-dee-dee-dee") and songs. At that time, Black-capped Chickadees occurred ONLY in the Great Smokies, the Plott Balsams and Richland Balsams. In the Smokies, there was no overlap in populations during the breeding season and there was no evidence of hybridization (no mixing of vocal characters and no pattern of intermediate or abberrent vocalizations). In the Balsams, the breeding ranges adjoined or overlapped and there were distinct elevational bands (zones) where vocal characters were blended and where there was mixing of vocal types (Black-capped songs and Carolina calls from the same bird). Findings were entirely consistent with those of Jim Tanner who surveyed the same areas some 25-30 years eariler.
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