Monday, 8:00 AM. 8 degrees, wind WNW, calm. The sky is overcast and a very light snow is falling. The Island is just barely visible, a long low smudge on the eastern horizon. The barometer predicts snow.
I am no ornithologist, but the cardinal is one of those birds that is always talked about: “didn’t used to stay the winter,” “must be getting a lot warmer, see a lot of those southern birds now,” etc. They certainly have been pretty common winter residents in Bayfield since our own arrival here almost eight years ago. Birds are highly mobile and certainly can take advantage of changing habitat factors such as climate, and may very well increase their range in a matter of decades or more, and probably can decrease their range just as rapidly if conditions warrant. My 1917 Birds of America cites southern Wisconsin as within the breeding range of the cardinal, whereas my 1963 Birds of Wisconsin indicates their range is throughout the state, an evident increase in year-round range of hundreds of miles within half a century. There is an interesting 1947 study by Howard Young, available online, which tracks the expansion of the range of the cardinal in the state starting in 1900. The epicenter of the cardinal population is indeed south, in Kentucky and Missouri, and they have spread continually from there, the northern extreme of their range seemingly being the Boreal forest region, of which Bayfield is just on the southern fringe. The Great Plains is evidently a barrier to the west. So it makes some sense that people hereabouts have witnessed and remember fluctuations in winter and breeding residence of these birds over the years. Another thing to consider in animal and bird ranges; are the habitats the change element, or are the animals and birds adapting to an unchanging habitat? In any case, whether measured in decades or centuries, the cardinal is a southerner who had become a Yankee as well.
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