Blane Klemek column: Migration not just for the birds
Last week I wrote about the fee-bee song of male black-capped chickadees -- a sure sign of transition from one season to another. As such, it won't be long and we'll notice other signs of seasonal renewal.
Horned larks will be arriving shortly, followed by Canada geese and other species of waterfowl. Already bald eagles are establishing pair bonds at their nest sites. But, next month is when it all begins in earnest -- March Migration Madness, if you will.
Migration is a phenomenon that we mostly ascribe to birds. But migration occurs in other creatures as well. Many species of whales migrate enormous distances each year from wintering areas to calving areas.
Each autumn, monarch butterflies migrate hundreds of miles from north to south. Elk and deer inhabiting the Rocky Mountains migrate each fall from higher to lower elevations to take advantage of milder wintertime conditions in mountain valleys. Even some populations of white-tailed deer in the northern regions of Minnesota migrate, though never very far and usually only to traditional deer yards like cedar swamps and other coniferous woodlands.
Migration has evolved so wildlife can remain active year-round. Obviously, this is only part of the reason, because many species of animals do not migrate at all and remains in an area year-around. Some species, however, have solved the problem of coping with extreme environmental conditions by hibernating or slumbering inside cozy dens throughout the coldest of winter days.
Bears, ground squirrels, skunks and raccoons are only some of the animals whose only migratory routes encompass a known territory to a suitable hole in the ground, cavity inside a log or tree or, in the case of bears sometimes, a nice spot on the ground under the overhanging limbs of a pine, balsam or spruce.
Still, there are other species of wildlife, like gray, red and fox squirrels; rabbits and hares; voles and mice; foxes, coyotes and wolves; and many species of birds that seem to find no reason at all to vacate Minnesota each winter. And, as mentioned last week, some birds stay in Minnesota and other northern-tier states throughout the winter. Further still, some species of birds actually migrate to Minnesota to spend the winter, not leave it. The snow bunting is a good example of a bird that migrates south to Minnesota for our "tropical" winters. Come spring, the snow bunting returns to the Arctic Circle to breed and nest.
The reason that many birds migrate is often food-driven. Ducks and geese would have no problem spending the entire winter right here if food and water were readily available. And some actually do remain here if conditions are right. But just how they migrate is even a more intriguing question.
It is believed that migration is possible among species through a combination of factors. With some birds, navigation is accomplished through learned experiences across known routes, over known landmarks, to known destinations. Still, too, the stars and sun play important and vital roles for those species of birds migrating during the night and day. And, stranger yet, the geomagnetic fields of the earth provide some species a means of orientation. Even the sense of smell helps some birds, like pigeons, literally smell their way home.
I recall one March night several years ago when I took a walk under the light of a full moon. I happened to have my binoculars with me because I intended to look at the surface of the moon at its crater-pocked surface. As I stood looking at the moon through the optics, an unexpected sight delighted me. I at first thought it to be an isolated event, but it soon turned out to be nothing but; a major migration of neo-tropical birds was taking place right before my eyes. For minutes on end, I witnessed silhouettes of birds flying across the face of the illuminated moon. It was the first time I had ever seen such an event.
But perhaps one of the most awe inspiring migratory spectacles I have ever observed occurred in the Prairie Pothole Region of North Dakota about a dozen years ago during a springtime goose hunt in the month of March. Tens of thousands of ducks and geese were flying everywhere I could see.
On one particular "bluebird" day with scarcely a hint of a breeze, endless flocks of migrating geese and ducks steamed northward. This great event was the result of a several-day layover because of foul weather that kept many birds grounded. But on this day, when the weather broke, it was as though feathered floodgates were opened.
I couldn't help but feel the same sense of urgency that those migrating birds were experiencing as I stood staring skyward, aching neck and all, at the wondrous sight of thousands and thousands of ducks and geese of nearly every kind were eagerly flying to their nesting grounds.
The March migration will soon be upon us. Longer days are likely the catalyst that brings about hormonal changes, which subsequently alter avian behavior and physiology that stirs migratory birds into long distance northern flights. Certainly, all factors relating to migration are as intertwined as they are convoluted, if not partly unknown despite all the science available on the subject.
But this we know: A favorite time for wildlife enthusiasts will soon be here. This is the time of the year that arouses all living creatures, including us. It's an awakening, it's the springtime migration, and it's a grand time for us all as we get out and enjoy the great outdoors.
BLANE KLEMEK is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org.