Minnesota is home to many different species of birds. Some, such as the ruby-throated hummingbird, eastern bluebird, and rose-breasted grosbeak, are only part time residents. These birds arrive in our woodlands, fields, and backyards without fail every spring, but, come autumn, migrate to more hospitable climates far away where snow doesn’t fly and Arctic winds are rare. Other birds, like white-breasted nuthatches, downy woodpeckers, and common ravens are year-round residents and seem unaffected by weather extremes.
Still, there are some birds that are here for only a spell as they continue north or southward in the spring and fall during the annual migration. Birds that readily come to mind that fit the bill are tundra swans, snow geese, Harris’s sparrow, and fox sparrow. These latter birds spend the nesting season in the far north of Canada, Alaska, and the Arctic Circle. Minnesota, it turns out, is all things to some birds, not quite enough for the entire year for other birds, and suitable as only a stopover for others intent on getting somewhere else.
In the world of woodpeckers, a group of birds that outwardly appears capable of surviving Minnesota’s seasonal variation, seven out of the nine or so species of woodpeckers inhabiting Minnesota are commonly to rarely observed throughout the year, while two species migrate to the state for only a few months during the nesting season: yellow-bellied sapsuckers and northern flickers. This woodpecker duo seem somewhat the oddballs of the bunch. A close examination, however, reveals why spending the winter in Minnesota is not very high on their respective wish lists.
Yellow-bellied sapsuckers migrate north to our neck of the woods every spring from as far away as Central America, Mexico, and southern United States. As their name so aptly suggests, “yellow bellies” are indeed sapsuckers and, in Minnesota - as we all well know - sap doesn’t run in the wintertime, hence the primary reason they head south come fall.
In any event, yellow-bellied sapsuckers have the unique habit of drinking sap from favorite trees such as paper birch, box elder, and mountain ash. Sapsuckers are known to tap over 250 different species of trees and vines. They accomplish “sap-sucking” by drilling “sap wells” in neat rows or columns on tree trunks and branches. Once holes have been created through the bark, the birds eat away the inner bark and cambium layer and drink, not suck, the sap that flows from the wells.
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Sapsuckers also eat insects that are attracted to the sap; they forage for insects in manners typical of other species of woodpeckers through probing, prying, and pecking into dead or alive wood with their bills; and the birds consume fruit, berries, and buds when in season. Yet while sap makes up only about 20-percent of a sapsucker’s diet, they won’t stick around for very long when temperatures begin hovering at and below 32 degrees Fahrenheit. A sapsucker exodus occurs every fall when colder temps slow the flow of sap.
The northern flicker is another species of woodpecker that finds Minnesota to its liking, but only during the season-of-plenty. You won’t find a flicker hopping around on a snow bank or noisily exclaiming its steady, strong, and familiar kwi-kwi-kwi-kwi call in the dead of winter!
You may have noticed that large flocks of flickers have begun gathering together as they prepare to migrate. And you might have also noticed when observing flickers that they spend a considerable amount of time on the ground behaving much like American robins do. That is, hopping about our backyards and other short-grass clearings searching for food. And what are they looking for? You’re right if you guessed insects, but specifically it’s mostly ants that flickers are hunting for.
Unlike all other North American woodpeckers that do most of their hunting for food by cascading up and down the trunks and limbs of trees, flickers are more content, probably more adapted, at digging into the soil with their chisel-like bills to unearth ants and other insects to eat. Once a treasure-trove of ants is discovered, flickers use their long barbed tongues to lick’em up.
Obviously, when the annual freeze occurs and frozen sod is covered by snow and ice, finding ants and other goodies becomes impossible, so flickers, like yellow-bellied sapsuckers, migrate southerly until more suitable conditions are encountered for finding food.
And so it is; some critters stay, some critters visit, and some critters go elsewhere when the seasons change. But it all makes living in Minnesota - for us - a fun-filled, four-season adventure full of avian diversity and beauty as we get out and enjoy the great outdoors.
(Klemek is a DNR Wildlife Manager. You can contact him at bklemek@yahoo.com .)
