Black-throated Blue Warbler

I banded this Black-throated Blue Warbler on 13 September 2018 in our backyard. I encounter this species once or twice a year, at most, but not every year. My observations are all in the fall. This species has an odd range, covering the Minnesota Arrowhead and southwestern Ontario to the northeastern United States and southeastern Canada south through the Appalachian Mountains to northern Georgia. Most winter in the Greater Antilles, and also in south Florida, the Yucatan, Belize, and even further south through Central and northern South America. Holmes et al. (2017) do not even show the species’ occurrence elsewhere in Minnesota. eBird, however, shows Black-throated Blue Warbler records scattered across the western United States, during migration and winter. It almost appears that young birds are genetically programed to migrate correctly to the southeast, but some birds inherit a reversed map and head southwest. As a result, quite a few records are from southern California.