Sunday, December 1, 2013

Cackling Goose

Among the Canada Geese roosting on Carleton College’s Lyman Lakes, Erika and I found a few Cackling Geese. We were alerted to the presence of these small geese by our BirdsEye app on our new iPad. They had been originally reported by Gerry Hoekstra. Our first Cackling Goose is in the top photo—the closest bird on the bottom left-hand corner. I previously summarized how to identify Cackling Geese—suffice to repeat here that the Cackling Goose is generally smaller with a tiny, stubby beak. Note, however, that larger races of Cackling Geese overlap in size with smaller subspecies of Canadas. Mark Stackhouse warns “identifying Cackling and Canada Goose [sic] by size alone will only work at the extremes of both species."
We took the second photo to illustrate some of the differences between the two species. Note the feather stuck to the tip of the smaller Cackling Goose. In the field, we did not notice the white forehead on the larger Canada Goose. This variation in head pattern is occasionally found in all populations of Canada-like geese and is illustrated in Sibley(2000). Some internet sites erroneously suggest the white forehead is characteristic of the largest race of the Canada Goose, often called the Giant Canada Goose.

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