Dawson Trail Dispatch, written by Norm Gregoire, December 2024
Page 14 https://issuu.com/dispatch222/docs/dawson_trail_dispatch_december_2024
Love them or hate them, winters in Manitoba are inevitable. How we choose to spend the months of cold, snowy weather differs from person to person. Some people put on an extra layer and head outside to enjoy the fresh air. Some stay inside where it’s warm and protected. Others escape the winter completely by vacationing in the south. Every living creature that calls Manitoba home has their own way of spending this time of year; many of them resemble our own coping mechanisms.
When we think of how to get through the winter, one of the first thoughts is to avoid it altogether. For many species that call southern Manitoba home during the warmer months of the year, migrating south is the preferred choice to avoid the cold. This is most common with the many species of birds found in the province. Some birds, like the bobolink, have incredible migrations that can take them as far as Argentina to overwinter. There is risk to these migrations, including having to deal with variable weather, collisions with man-made structures along migrating routes, and being more susceptible to predation.
Although we think of birds as being the main migrators in our province, one of the most impressive migrations is done by an insect, the monarch butterfly. A creature that weighs less than a paper clip will make its way from southern Manitoba all the way to central Mexico, where they overwinter. It’s also impressive to think that the Monarchs that are making this journey were born in Manitoba during the summer and have never been to their overwintering grounds. How they know where to fly to is still somewhat of a mystery to researchers.
Another butterfly, the Powesheik skipperling, has an entirely different way to overwinter compared to the monarch. Like most insects found in Manitoba, the Poweshiek enters a state of diapause. This is a state of dormancy where an insect will suspend the development or growth of itself through challenging environmental conditions. The Powesheik spends the winter in a larval (caterpillar) state nestled in the dead grass and other plant material layer called the thatch layer, which provides some insulation from the elements. On top of the thatch layer, another important insulating layer, snow, is key to a successful overwintering.
When speaking of diapause in insects, the more familiar term of hibernation may come to mind. Hibernation is a term that is mostly associated with mammals such as ground squirrels. Brumation is another similar term that is used to describe the winter dormancy period of reptiles and amphibians like the snapping turtle and northern leopard frog. All these overwintering-dormancy terms differ slightly, but the key points to all are that the species bodily functions decrease significantly or become dormant until warmer weather and easier living arrive in the spring.
A special shout-out goes to the species like white-tailed deer who survive the winters by relying on putting on an extra layer of fat to survive through the lean winter months. This is my own personal way of surviving the deep cold, and luckily for me, the holiday feasts come at a great time to add a little extra insulation for the remainder of the winter.
Adventures with Nature Norm
If you are interested in learning more about how Manitoban species survive our winters, join the next Adventures with Nature Norm event on December 21st from 10 am to 12 pm. I will be hosting a trail walk followed by an indoor presentation at the Weston Family Tall Grass Prairie Interpretive Centre. For more information or to register, please contact info@sharedlegacymb.ca.
Photo: Sunrise Corner