by Greg Mayer
On Christmas Day, I went down to the harbor in Racine, Wisconsin, and saw a male and female pair of mallards (Anas platyrhynchos) amidst a group of Canada geese (Branta canadensis).
Canada geese were migratory in this part of Wisconsin when I first moved here (1992), disappearing for a month or two at the height of winter. In even earlier times, they were not even breeding here, just passing through on the way to and from their more northern breeding grounds. Now they are year-round residents, with pairs setting up breeding territories starting in February-March. (On the campus of the University of Wisconsin-Parkside, the nesting sites are atop buildings, a shift from the ground nesting habits they had in the 1990s.) They join up in flocks after the breeding season, frequenting open water (as at Lake Michigan, shown here) and farm fields, which have unharvested corn and other food supplies. I’m not sure what has caused them to stay year round, but the local increase of development– leading to higher temperatures (heat islands), more open water, year-round lawn grass growth in some areas, and more handouts from people– along with global warming– leading to higher temperatures in general– may be contributing.
As I approached to get a picture, I realized there were many more mallards than a pair– 17, in fact, among the 23 geese. Also, the mallards were much more apprehensive about the approach of a person on shore. As you can see, they are all streaming away, while the geese remain serenely contemplative.
Canada geese are resident year round here in far Northern California as well. I live near a large pond, and have witnessed the mallards mixed in with the geese and how nervous any approach makes them. A pair of the geese nest here every year, and our little community enjoy watching the goslings as they grow and fledge.
Even here in the south of Kansas we have year round ducks and geese. If the ponds freeze over which is not for long they have to go find water but otherwise they are here.
Remarkable that they are resident now, but that is true all over the northern hemisphere…