We have had cold temperatures; now we have snow. Does that mean the 2019-2020 winter season will bring an irruption of birds from Canada into Minnesota? Those of us who lean toward the outdoors for wintertime entertainment certainly hope so.
But, well, things don’t look so good.
Some bird species we consider winter residents are actually migrants from Canada. Species such as pine and evening grosbeaks, redpolls and crossbills often flock into the United States in what are called "irruptions."
Reasons for irruptions of birds in the northern U.S. are not fully understood, however, a scarcity of food in Canada is considered a principal factor. For example, a major winter food source for crossbills are the seeds of spruce trees. They use their unique shaped beak -- the upper and lower mandibles cross -- to extract the seeds from the cones. This season, according to reports from Canada, spruce cones are abundant. Pine siskins also relish spruce seeds. Redpolls are seed eaters, too. They favor birch catkins. And, well, birch catkins are abundant in Canada, too.
Pine grosbeaks, another irruption species, rely immensely on the seeds of ash trees, and the fruit of mountain ash for their winter food. Again, the word from Canada is there’s a wealth of ash seeds and mountain ash berries this winter which does not bode well for high numbers of sightings in Minnesota of these exceptionally tame birds.
Thus far, feathered visitors from the north have been relatively scarce. A scattering of pine grosbeaks has been reported along the north shore in northeastern Minnesota. About two weeks ago I had two Bohemian waxwings in my yard where they fed on crabapples, but I have not seen them since. Others have noted seeing a few Bohemian waxwings in central Minnesota, but not the numbers that we often experience, although it is still early in the winter season. Waxwings also dine on mountain ash berries so they might be a rare sight all winter.
Owls are particularly popular guests from Canada -- the large, stately great gray owl being the most popular. Great grays have been sighted in the Sax/Zim Bog west of Duluth, but that location has resident great grays so that might explain their presence. Hawk owls have also been spotted
Owls often invade Minnesota when vole (not mole) populations are low in Canada. I’m not sure about vole numbers in Canada this season but I do know there is an abundance of the mouse-like critters around Brainerd, but I’m not seeing as many last fall. One can only dream about an owl irruption like the one we experienced in 2005, when that winter, while on an owl prowl in Aitkin county I observed 67 great gray owls in one afternoon.
Will songbirds and raptors of the north move southward into the Brainerd area before the end of winter?
We can only hope.
Remember, though, we have plenty of local songbirds to uplift us on winter days. Cardinals, blue jays, chickadees, nuthatches, and several species of woodpeckers, and others, are always out and about.