In this episode, we’ll look at some of the many ways that local animals and birds adapt to winter in the Canadian north. We’ll also look at the history of snowshoeing.
Story 1 – Adapting to Winter
There are a myriad of ways that animals make it through the winter and we’ll look at just of few of the more common strategies. One of the most effective is the adaptation of huge feet like those of the snowshoe hare and the lynx and that will lead us into our second story of the day – the history of snowshoes. It was natural for humans to follow examples of the animals around them in developing one of the most important transportation systems in history.
As the temperatures begin to drop and the snow to fall, most of us are digging out our winter wardrobes, boots, mitts and toques – that’s a knit cap for our non-Canadian listeners – and getting ready to tough out the long winter months. Have you ever wondered what our local wildlife do to make it through the next 5 or 6 months of cold temperatures?
If we look at every animal and bird that spends their summers in the north, they all can be categorized into one of 3 categories – winter avoiders, winter tolerators, or winter lovers. Every single animal and bird falls into these three categories so let’s take a look at them one by one.
What is a winter avoider? The most obvious example are the tundra swans that are beginning to gather on ponds as they migrate south to warmer climates – much like a lot of Canadian snowbirds packing up for Mexico or Arizona to avoid the frigid temperatures. For many birds, like the American Robin, the best strategy is to simply leave the area and avoid winter altogether. Most will head south to warmer climes and more plentiful food supplies while others, like the harlequin duck and some bald eagles, will instead migrate westward towards the coast and milder maritime conditions.
Another way to avoid winter is to simply die! Many insects follow this strategy. The adult stage may die but larval stages or eggs may survive the winter to emerge the following spring and repopulate the area. Some adult insects can find protected areas where they can survive the winter in a dormant state. Locally the daddy longlegs can be found in places like the rat’s nest cave which serves as a hibernaculum. Since the caves stay warm all winter, you can find fist-sized clumps of these arachnids all huddled together to stay warm. Contrary to popular belief, daddy-long-legs are arachnids, but they are NOT actually spiders but that’s a story for another episode.
A final winter avoidance strategy involves dormancy. This includes hibernation but also includes other dormancy strategies. Bears are often considered a hibernator but they really are more of a winter sleeper. What’s the difference you ask? If you were to dig up a ground squirrel in the dead of winter and do a physical exam on it you would find that it’s heartbeat and respiration drop to just a few per minute and its body temperature can drop right down to freezing, or even a few degrees below. It takes very little energy to keep these little guys alive for the 5 or 6 months that they will remain in their dens. Now were you to dig up a grizzly bear in the middle of winter, please don’t try this at home, the first thing you would notice is that it WOULD wake up. If you were then to do the same physical exam, you’d find that its heartbeat, respiration and body temperature fall just slightly below what would be normal were they up and active. This means that they need almost as much food energy every day they are in their den as they would were they up and active. It’s this drive to store fat that has them in a constant hunt for high-calorie foods during the summer months.
Some animals will just go dormant for short periods. The red squirrel stays active most of the winter, but when the temperatures get unbearably cold, they will go dormant for a few weeks or so. These brief periods of dormancy are called torpor and essentially they’re saying “wake me up when it warms up a bit”. This allows them to stay active most of the winter but sleep away the worst bits.
We also have one of the most unique animals on the planet here as well, the northern wood frog. While ground squirrels can survive in a deep state of dormancy with very low body temperatures these tiny amphibians have them all beat. They freeze solid. They are, by all clinical definitions, dead. They have no heartbeat, no kidney function, and no brain activity. They are as hard as a rock, yet in the spring, as the sunshine warms their frozen bodies, suddenly the heart begins to beat and they wake up with no apparent ill effects from their frozen winter.
What about those animals that can’t avoid winter altogether? Well for some, they simply need to devise strategies to allow them to tolerate the difficult months. If we look at mule deer and elk, they really don’t have any physiological adaptations to help them get through the winter. Even a small amount of snow accumulation can force a mule deer into a bounding gait and within a short time, the energy expended by movement can outweigh the benefits of that movement. One strategy is to hang out with friends. This ‘yarding up’ as it is known allows them to take turns breaking trail and reduces the energy expenditure required for each individual. They will also gather in places like denser coniferous forests where there will be lower snow accumulations.
Small animals also have a very difficult time surviving in winter. Small animals lose heat to the environment much faster than large ones. This means that for a tiny vole, staying exposed to the cold winter weather can be very dangerous. Luckily it never gets cold under the snow and so beneath this insulating blanket, there is an entirely new habitat which we call the subnivean. Here mice and voles stay active all winter in tunnels and by staying beneath the cold weather, they can stay warmer and survive until spring. Other animals like my favourite predator the pine martin, spend part of their time above the snow but also lose a lot of heat to the environment. That’s where all the downed trees play an important role. Beneath these trees will be natural hollows or snow caves. This not only offers a warm place to get out of the elements, but it also gives them access to that subnivean world full of tasty mice and voles. In another episode, we’ll look at the subnivean in much more depth.
Finally, let’s look at an animal that absolutely loves, loves, loves the winter – the moose. Moose are a remnant of the ice age and are uniquely designed to thrive in cold winter climates. Unlike mule deer which struggles to move in the snow, moose are able to walk through deep snow. Their hooves have a total of four toes. They have two large toes that form the hoof. These are widely spread to give them a good grip and enlarges the surface area of the hoof. They also have a pair of dewclaws that combine with the hooves to help give them support in the snow. In addition, their long legs give them the ability to walk effortlessly in chest-deep snow. Their legs simply come straight out, move forward and go straight back down. To see a moose run through deep snow is a truly amazing sight. In addition, they can lower their body temperature by several degrees during the winter months. This has the same effect as lowering your thermostat at home. It dramatically reduces the amount of energy they expend and, at the same time, reduces the amount of food they need to take in.
There are a few other winter lovers here in the high country…the snowshoe hare and the lynx. These two animals are examples of coevolution. Snowshoe hares evolved very large feet to allow them to avoid winter predators. This gave them a great advantage simply because their large back feet allowed them to float on top of the snow surface. Over time, their primary predator, the lynx, developed the exact same adaptation. To watch a lynx walking, you are immediately struck by the immensity of their paws. Their tracks are almost as large as those of a cougar, but they weight only about 10 kg compared to the 40+ kg of an average adult cougar. Their large feet help them to float on top of the snow and keep up with their high-speed prey.
These are only a few of the myriad of ways that animals have adapted to winter. In keeping with the snowshoe hare our next story will offer you everything you need to follow in their footsteps.
Story 2 – The History of Snowshoes
Humans are the ultimate predator on the landscape and throughout the history of human evolution, we have looked to nature to help us to adapt, to hunt and to survive. For thousands of years, the peoples of the north have been fashioning various versions of snowshoes to allow them to imitate the natural simplicity of the foot design of the lynx or snowshoe hare. The very oldest snowshoe ever found, was discovered in the Italian alps and has been dated to between 3,800-3,700 BC. This makes it some 500 years older than the 5,300 year Iceman known as Ötzi. They were made of birch twisted to make an oval frame. It is entirely possible that snowshoes were already an ancient invention by this time. Humans are great observers of nature and they would have likely looked at the strategies of animals around them and gradually experimented to find ways to enable them to travel more efficiently through deep snow without sinking in.
It is also likely that numerous peoples from cold climates may have independently come up with varying designs of snowshoes using locally available materials and craftsmanship. It is quite common for distant peoples to find similar solutions to problems and various arctic peoples would have all been confronting the same challenges.
Trading networks would have also allowed the technology to spread throughout polar regions and perhaps, at some point across the Bering Strait and into North America. This theory may have holes in it though since the Bering Strait migration theory has recently been disproved in favour of a coastal marine migration theory. That being said, however, they arrived they would have also brought with them traditional knowledge and may have introduced the snowshoe to the new world.
In North America, our first nations developed very unique snowshoe designs which generally were made up of a bent wood frame with a mesh made of rawhide strips. While the basic designs varied, the principal was always the same – increase the surface area of the foot to allow the wearer to walk easily on the snow surface. As European fur traders and settlers came to the new world, they learned how to survive from the natives and adopted the snowshoes to allow them greater access to the winter wilderness. As important as the voyageur canoe was in the opening up of Canada, the snowshoe extended our ability to explore once the rivers had frozen over. They were one of the most critical tools in every fur trader and explorers kit. They deserve their place in the history books with the canoe and the red river cart.
As early as 1840 snowshoeing began to be used recreationally and clubs like the Montreal Snowshoe club were created. They hosted annual races and helped to increase the use of snowshoes as more of a recreational tool as opposed to its long tenure as a simple transportation device.
By the late 1800s, the allure of the snowshoe began to decline as European immigrants introduced Canadians to downhill and cross-country skiing. As more and more people were drawn to these new pursuits, the number of snowshoe clubs began to decline. In the 1980s, new technologies brought innovations to snowshoe design that began its renaissance back into the forefront of winter recreation. It was at this time that we began to see aluminum frames with nylon decks. It also saw the addition of spikes under the snowshoe to aid in climbing and traction. Within a short period, snowshoes began to see a very quick improvement in quality and design as manufacturers competed with each other to find the most innovative improvements.
All snowshoes follow a fairly simple design concept. You have a large surface area with a harness and pivot towards the front end of the shoe. You strap or harness (depending on the design), your boot in the harness and it allows your foot to pivot with your toes dropping below the surface of the shoe. This allows you to use an almost normal ‘toe-off’ gait while the snowshoe remains relatively flat. Essentially, you’re just dragging the shoe along and its tail will drag on the surface. This dragging character helps the snowshoes to track into a straight line. It also means that there is no reverse! If you try to back up, the tail of your snowshoes will dig into the snow and you will likely end up wallowing in the snow to the delight of your friends. Wait – before you fight your way to your feet – selfie!
Newer snowshoes typically fall into one of two main designs. The most popular are the tubular aluminum frames with a nylon deck and some crampon style claws beneath the toe bed. This style accounts for the vast majority of popular snowshoes on the market today and is the design you’ll see companies like Atlas and Tubbs marketing today.
In 1995 though MSR introduced a one-piece plastic snowshoe with traction bars along the periphery to give superior grip on steep terrain. You could also add a flotation tail that would increase the surface area of the snowshoe for softer snow. This has now evolved into the current REVO Explore model which combines a plastic deck with an external traction wall that gives amazing grip on icy ascents. They have become a popular alternative to the more prevalent tubular designs that you’ll see in most outdoor stores.
Personally, I prefer the models by Atlas and Tubbs for most terrain. The MSR models are great for harder packed snow in steeper terrains. They don’t have the surface area for softer snow, but they have their advantage when doing steep climbs.
In my next episode, I’ll go through the process of selecting your first or next pair of snowshoes.