A potent cold front is forecast to drop through the eastern half of North America over the next few days. We birders hope that it brings the first significant wave of migrant waterfowl this season.
Indeed, more than other groups of birds, most of which either don't migrate or move in response to the solar cycle, waterfowl head south when their natural food sources are depleted or when lakes, ponds and wetlands freeze over. In that regard, their lives are more closely tied to the fickle nature of weather patterns (and thus to climate change) than most wildlife.
And unlike human snowbirds, who head south to escape winter, waterfowl will often stop short of their traditional wintering areas if relatively mild weather encourages them to do so. Whether global warming eventually halts their seasonal migration altogether remains to be seen; availability of food rather than weather may become the determining factor.
