Winter Finch Forecast

Those among us that have bird feeders in our yards notice variations in the species of birds visiting the feeders from year to year. Some species are regular visitors, but others such as redpolls and pine siskins are quite sporadic. Furthermore, when these species do show up there is often a sort of invasion or irruption.

Many of these irruptive species are finches that typically spend their winters in the northern coniferous forest, and a food shortage up north is the most common cause of these irruptions. Actually there may be two irruptions: one in the late fall or early winter due to a poor fruit or seed crop. Another irruption may occur toward the end of the winter if the finches’ food sources have been exhausted.

Ron Pittaway, an Ontario ornithologist, has been publishing a Winter Finch Forecast the past few years. Each year, with the assistance from friends and colleagues, he assesses the food crops of various species of finches across parts of Canada and uses that information to predict the finches’ movements for the upcoming winter. The group of finches includes occasional visitors to North Dakota bird feeders such as purple finches, redpolls, pine siskins, and pine and evening grosbeaks. He also includes blue jays, red-breasted nuthatches, and bohemian waxwings in his predictions.

Based on his forecast for this winter, we are not likely to see many redpolls.. Their main winter food is birch seeds, and the birch trees produced a good seed crop across much of Canada last summer. It is expected to be similar for red-breasted nuthatches. They are specialists at eating conifer seeds, and there was a good crop of their seeds last summer as well.

We may, however, see a few more pine grosbeaks. Pine grosbeaks depend heavily on the fruits of mountain ash. Across much of the northern coniferous forest this past summer the fruit crop of mountain ash was quite variable in both quantity and quality. So be on the lookout for this interesting species, particularly if there is some mountain ash near your home. The evening grosbeak populations are increasing in areas of Canada with spruce budworm outbreaks. These outbreaks are moving westward in Ontario, so perhaps we may get lucky and see a few of these interesting birds this winter as well.

Chuck Lura

Natural North Dakota is supported by NDSU Central Grasslands Research Extension Center and Minot State University-Bottineau, and by the members of Prairie Public. Thanks to Sunny 101.9 in Bottineau for their recording services.

Click here to see the Winter Finch Forecast