Writing in the Snow

Qali Growing up, I would hear people quote this statistic: “Eskimos have more than a hundred words for snow.” Actually, I still hear people rattle off this little ‘fact’, especially in winter.  However, there are a lot of problems with this statement, not even including the fact that the indigenous people of North America’s tundra and Arctic regions are known as Inuit, not Eskimo. No, what really grates on me about this blanket statement is the implication that it’s somehow weird to have so many words to describe one thing.

When it’s something that makes up a very large part of your daily life during a significant portion of the year, why wouldn’t you take the time to describe it as accurately as possible? The English language has several words for rain: showers, downpour, drizzle, sheets, so why not snow, especially in light of the fact that it sticks around a lot longer than its warm weather counterpart.  Actually, as a Canadian, I’m surprised that we, as a population, haven’t developed more words beyond flurries, blizzard and slush to describe this white stuff that blankets much of the country for four to six months out of the year.

To do that, we have to turn to other cultures and languages. While the true count is well under one hundred, many Inuit dialects have several useful words to describe the incredible variety of snow that we can encounter throughout the course of the winter.  For those of us who live in forested areas, one handy word to know is qali. It refers to the snow that builds up on the branches of trees, glazing limbs in white and making it look like someone attacked the woods with a decorator’s bag full of royal icing.

I was lucky to have learned several Inuit terms for snow as part of some of my undergraduate university courses and like many people who study winter ecology, they’ve been part of my lexicon ever since. So, it took a bit of digging to figure out where the word qali comes from. According to William Wonders, who wrote the book Canada’s Changing North (2003), the word originates from the Kobuk Valley Inuit of northwestern Alaska, along the edge of the treeline.

Qali can range in thickness from a light dusting that could almost be mistaken for hoar frost to heavy globs of wet snow that drag beleaguered limbs to the ground under its unrelenting weight. All along that spectrum, it has a significant impact on the ecological community.

Many winter residents are affected by qali. Spruce grouse and squirrels that regularly feed on cones often find themselves driven down to the ground by a particularly heavy layer of qali. The snow-covered branches can be hard to navigate, forcing these species to search elsewhere for food. On the other hand, qali can make some food more accessible. With particularly heavy wet snows, the qali that builds up on young birches, willow and aspen pulls the flexible branches down, bringing the young, tender tips within reach of hungry cottontails and snowshoe hare. These contorted trees may also provide shelter for a whole host of wildlife.

You might not have ever realized it, but if you live in an area that experiences snow, qali has likely affected you at some point and I don’t mean that moment when you accidentally brush up against a laden branch and send an unwanted shock of snow pouring down the collar of your coat. I’m talking about more significant impacts. Qali can be very heavy and often trees buckle under the weight taking down whatever else is nearby, which is some cases are power lines. I know I’ve spent the odd cold, snowy night in the dark, waiting for hydro to be restored.  These qali-broken trees also open up the forest floor to new growth, creating pockets of mini forest succession and driving the forest cycle on a smaller scale.

Snow is an amazing thing and qali is only one small facet in a dizzying array of diversity, which thanks to northern cultures, we’re able to describe in accurate and imaginative ways. So, next time you take a winter walk surrounded by white, take a moment and discover that variety for yourself and maybe even create your own words to describe it.

 

In the Bleak Midwinter

Insulation - chickadee warming its feetIt was minus 40 Celsius with the wind chill the other morning. The bite of the air stung any carelessly exposed skin and the snow squeaked like Styrofoam underfoot. Wrapped up in my shearling coat, I couldn’t help but watch in fascination as a nearby mountain ash came alive with foraging Pine Grosbeaks and the cheerful chirps of chickadees and nuthatches filled the frosty air, reminding me just how incredible these tiny winter residents really are.

Chickadees, for example, weigh not much more than 10 g, about the same as two nickles. Yet, they can survive quite comfortably in temperatures that would leave us frostbitten and shivering.

Winter birds accomplish this seemingly unfathomable feat in a number of different ways. Firstly, they’re wearing a down coat. Those of you who own one know just how warm they can be and for birds, that insulation is part of the standard package. Feathers are a remarkable insulator. Comprising only about 5 – 7 % of a bird’s body weight (that’s half a gram on a chickadee), the air trapped within them makes up 95% of that weight’s volume, creating a thick layer of dead air that traps heat generated by the body, preventing much of its loss even on the coldest of days. Many winter residents grow a thicker winter coat, much like mammals, augmenting their feather count by up to 50 %. Fluffing feathers increases their insulation factor even further (about 30%), making them a very efficient way to keep warm in the winter, so efficient, in fact, some birds, like Great Gray Owl can actually overheat in the summer.

While some species, like Ruffed Grouse and many owls, grow feathers, along their legs and feet, like fluffy winter boots,  most songbirds’ legs are bare, thin sticks of sinew, blood and bone exposed to the elements. Although birds can tuck these delicate structures up into the warm cover of down when temperatures really plummet, most of the time they’re out in the open. So, why don’t they freeze and why isn’t all of a bird’s body heat lost through these naked limbs? Bird legs are marvels of biological efficiency, having been streamlined by millennia of evolution into sleek structures with very little muscle and few nerves, using instead pulley systems of tendons and bone to accomplish movement. These tissues, along with their scaly coverings have very little moisture and are less likely to freeze than flesh and skin.

Birds also have cold feet. Using a common natural system called a countercurrent heat exchange, our feathered friends keep their feet upwards of ten to twenty degrees colder than their core body temperature. Countercurrent Heat Exchange System in a bird's leg. by Heather HinamWarm arterial blood on its way to the feet pass right next to colder blood coming back towards the body through the veins. Heat wants to reach a point of equilibrium, so warmth from the arteries passes into the veins which carries it back into the body. Because the flows are running opposite to each other, it’s impossible for the heat balance to ever reach equilibrium, so by the time the blood gets to the feet, it’s much cooler than when it entered the leg and all that precious body heat has been kept where it needs to be, in the core.

However, as most of us who have experienced a true northern winter know, a coat alone isn’t always enough. There has to be heat to trap in order for insulation to work over the long term. To generate that heat, many winter birds shiver constantly when they’re not moving. Ravens, whose feather count isn’t as high as some of its more fluffy distant cousins, actually shiver constantly, even when flying, the repeated contractions of their massive pectoral muscles acting like a furnace. Powering that furnace takes energy and cold-weather specialists meet those needs by upping their metabolic rate, in some species, to several times their normal levels. As a result, food is always a going concern in winter.

Many winter residents can only forage for food during the day, so keeping the internal fires burning at night can be a challenge.  Finding a warm place to settle in for the night reduces those metabolic needs.  Densely-packed spruce boughs or old tree cavities are perfect nighttime microclimates and many birds use them. Chickadees will often take it a step further, piling as many fluffy little birds as possible into an old woodpecker hole to share body heat, which may just be too much cuteness in one place. Ruffed Grouse take advantage of the insulative capacity of snow in a somewhat comical way. One cold nights, the birds dive head first into a drift and tunnel deeper into the snow, creating a cave known as a kieppi. Temperatures inside the kieppi can hover just around the freezing mark, even when it’s minus thirty outside.

So as we close in on the shortest day of the year and sink deeper into the cold clutches of winter, take a moment, now and then, to marvel at those tiny survivalists outside your window. Much of the technology that keeps us from succumbing to winter’s icy grip was adapted from them. Nature truly is our greatest teacher.

Sounds of Silence

White-tailed deerWalking through the winter woods I can’t help but feel an overwhelming sense of closeness with the world around me. Snow is nature’s greatest silencer, muting the world as it bathes it in white and it’s this silence that breeds a feeling of intimacy with my forest brethren. Shrouded by heavy bows and intermittent shadows, I feel my senses stretch through the quiet, reaching out for any sign that I’m not alone in my wanderings.

As I make my silent progress, I find myself wondering how the other inhabitants of the forest perceive this winter world. Whenever I get into one of these moods, my mind usually strays to the white-tailed deer, a species I’m fortunate to meet often on my woodland rambles.

We’re about the same size, a doe and I, and their soft, forward-facing eyes and expressive faces make them easy to relate to.

Though I know she could easily outrun me (especially since I’m a rather slow runner, even for a human), we have a bit more in common than we might first realize. White-tailed deer and humans perceive the world in much the same way. Deer, for the most part, are just a lot better at it.  They have to be. When you live you life under the constant threat of predation, it’s in your best interest to develop a sophisticated arsenal of early-warning systems and deer have plenty.

In deer, the nose knows everything that’s going on around them. With over 290 million olfactory receptors, deer can detect the faintest whiff of danger, even more accurately than their canine pursuers (who only have about 220 million). Both, however, seriously outstrip humans, with our rather paltry 5 million. Where do they put them all? The nasal region of both cervid and canine skulls is actually quite long and full of thin bones in a delicate scroll-work called nasal turbinates. In the living creature, these bones are covered with olfactory epithelium (skin with scent receptors) that picks up the tiniest of molecules. When actively sniffing, they fill their nasal cavities with as much air as possible, giving scent molecules a better chance of being picked up.

To further improve things, deer have a small, fluid-filled sack lying just on top of the palette called the vomeronasal organ (or Jacobson’s organ). This seems to function in a very specific type of scent detection – pheromones, something most mammals use in abundance and deer are no exception.  Whether we have such a functioning organ too is still being debated, but there is evidence that suggests it might play a subtle role in our lives.

Whenever I come face-to-face with a deer, I’m always drawn in by those liquid doe-eyes and this is one place where we have a bit of an edge over our four-legged friend, at least when it comes to how we see our world. Most people will tell you that mammals, especially ones that are active in the dark, don’t see colour. That’s not entirely true. The retina of deer eyes do have cones (colour receptors); they just can’t quite distinguish the same spectrum. A deer’s world is tinted in blues and greens, which makes sense, considering their main concern is picking out the right plants to eat. Still, don’t think you’re invisible to them as you walk through the woods in a blaze-orange vest. Recent work has found that they can pick out at least a hint of these longer wavelengths and with a visual range of 300 degrees while standing still and eyes that are highly sensitive to the slightest movement, a deer will notice you long before you even know you’re not alone.

Besides, if the eyes fail them, the ears wont. No matter how carefully I tread, I know that somewhere, the crunch of my footsteps is being collected by the large, rotating pinna of a deer’s ear. Their range of hearing is considerably better than ours, picking out much higher frequencies than we could ever hope to detect. The wide placement of the ears on the head and their ability to rotate them independently also make it possible for a deer to triangulate the source of a sound, much like an owl.

I know that I will never experience the world on the same level as any of my fellow forest inhabitants, but on a silent, snowy afternoon, I can’t help but want to try.

 

Suspended Animation

My world is getting quieter. As winter descends on the boreal forest, it’s like a veil of silence wraps around us, stilling all motion, save for the whisper of the wind across the newly-formed desert of snow.  One by one, the waterways stop, frozen in time, held captive by the solid grip of truly frigid temperatures.

Around here, the last body of water to succumb to this relentless creep of ice is the great Lake Winnipeg. Staring out over its endless expanse during the summer, it’s hard to believe that this inland ocean, the tenth largest freshwater lake in the world, finally gives in and stills beneath over a metre of ice.

It’s not a quick process and it actually starts a lot earlier than most of us realize. As the days get shorter and the air gets cooler, heat from the lake is slowly released into the atmosphere, often creating lake-effect precipitation, but that’s a story for another day.

As the water cools down, it becomes denser because the molecules’ natural vibrations slow and they cluster together. This denser water sinks deeper into the lake, letting warmer water rise to the surface and release its energy to the skies. This cycle continues until all the water in the lake reaches the same temperature. For freshwater, the magic number is 4 degrees Celsius, not zero, like you may have guessed. The water still freezes at zero degrees, but from 4 degrees on, the water molecules start to form the lattice work that ultimately becomes ice and at this point, this water is less dense than the rest of the layers below it, keeping it at the surface, where it starts to freeze.

At over 23,000 square kilometres, Lake Winnipeg doesn’t go quietly. November is a restless month, with flinty skies and often driving winds. Wild weather churns up this giant, but relatively shallow cauldron, breaking apart the fragile skin that forms on the surface, forcing it to start over.  Still, the cold eventually wins. The ice thickens and sheets knit together, sealing off the water below as it creaks and moans like a giant humpback whale trapped below the surface.

By the end of December, the ice will usually be thick enough to hold the weight of snowmobiles and tank-like Bombardiers used by the commercial fishermen to get to their harvesting grounds. By January, it’s strong enough to hold the weight of fully-loaded semi-trailers charging across the barren ice roads to deliver goods and supplies to towns that in summer can only be reached by air or by boat.

All the while, the lake is still very much alive beneath its frozen shell, reminding us of its presence with rattles and muted groans rising up from the depths. It’s a sound I never tire of hearing because it reminds me that the lake I love is still there, restless and waiting to be released with the warmth of spring.

Snakes on a Plain

Our month of change is coming to a close. May is an amazing month out here. In the space of only a few days, we witness a stunning transformation. In the blink of an eye, we manage to go from a barren landscape, just recovering from the ravages of a northern winter to a lush and verdant pastoral scene. Everything wakes up in May. Buds that have been straining against their confines finally burst free, the air fills with the scent of fresh pollen and the busy sounds of returning birds. Insects emerge from their hiding places, crawling out into the newly warm sunshine, but they aren’t the only creatures to find their way out of the darkness.

Up in my neck of the woods, we get to witness something truly remarkable. Every May in central Manitoba is marked by the emergence of the largest concentration of snakes in the world.

In a nondescript piece of prairie and aspen parkland, over 50,000 red-sided garter snakes (Thamnophis sirtalis parietalis) emerge after a six month sleep from large caves in the limestone bedrock, bringing the underbrush to life with their constant slithering.

So what makes this nearly 12,000 hectare bit of scrubland snake mecca? As they say in real estate: location, location, location. It’s not the habitat above the ground that counts, but what’s below it. Much of central Manitoba is underlain by layers of limestone and dolomite, dating back 300 to 500 million years ago.  Limestone can be dissolved by water and over time, it has eroded away large hollows in the area, creating a formation known as karst topography.  You can find crevasses and caverns of different shapes and sizes all over the Interlake region. I have quite a few further north in the forests I call home, but none are quite as large as the network of five caverns that crisscross under the Narcisse Wildlife Management Area.

They’re also pretty deep, stretching down below the frost line, which is what makes them so attractive to snakes, because unlike many other cold-blooded critters, snakes don’t keep well in a freezer. So, after waiting out the worst of the cold, their internal clock tells them it’s time to wake up, sending the snakes up to the surface.

When that happens at the Narcisse dens, it’s a sight to behold: thousands of snakes, milling about in the dens and and

Red-sided garter snakes at the dens in Narcisse, Manitoba

surrounding areas. They stick around for almost a month after they first glimpse the sunshine because this is one of the few opportunities for this otherwise solitary creature to mix up the genetic pool. As soon as they emerge from the dens, females are literally pounced upon by dozens of males, forming something biologists delicately describe as a ‘mating ball’. Males jockey for position, trying to be the one to get his sperm to the eggs. Because females can store the sperm before fertilization, it’s likely her young end up being the product of more than one father.

By the end of May, however, the furor dies down. Knocked up and ready to go, both males and females disperse to spend the summer feeding and, in the case of the females, giving birth. The dens and other hibernacula sit empty for the summer, but as the song says, we’ll see them in September.

Coming out of the Woodwork

Spring is sort of a fickle thing around here. I was so sure we’d seen the last of the snow, then I woke up to white and howling north winds over the weekend. The only saving grace was that it didn’t last for long.

Weather isn’t a very reliable indicator of the seasons up in the north woods. I’m pretty sure the only month I haven’t seen flurries of some kind is July. However, there are plenty of other indicators of the impeding spring.

While returning birds are always a good sign, it’s when I see my first butterfly that I know we’re finally starting to thaw for the year. Usually sometime around early April, I spot one, a Mourning Cloak (Nymphalus antiopa, pictured) or an Eastern Comma (Polygonia comma), basking on a branch or the middle of a gravel road, soaking up the now warmth-giving rays.  It’s always an especially fun juxtaposition when I find one sitting on top of some snow that just refuses to melt and it makes me wonder: what is a cold-blooded insect doing up and about so soon in the spring?

The reason these butterflies can get an early start on things is because they spend the winter hibernating as adults. Actually, calling it hibernation is putting it lightly. They tuck their delicate bodies into old woodpecker holes, cracks in the tree bark or between the shingles and wall boards of old or unheated buildings and then they simply let themselves freeze. Okay, well not quite. While they do let ice invade their bodies, these butterflies are quite particular about where the crystals form, keeping them confined to the fluid on the outside of their cells so that vital systems aren’t destroyed.

As the days get longer and warmer, they literally come out of the woodwork, flitting around in the sunshine, even when there is a foot of snow on the ground. How these butterflies and other freeze-tolerant organisms know when to wake up is still a mystery. They’re basically in a state of stasis all winter, their lives set on pause, so what exactly constitutes their alarm clock is still an unknown.

Once they’re up and at it, however, there is no time to waste. Mating begins right away, with males and females fluttering around each other before settling down to business. Once the eggs are laid on suitable host plants, like willow, aspen and birch, these harbingers of spring die off, leaving their genetic legacies to the next generation. It may seem like a short life, but most of these over wintering butterflies have been alive as adults for up to 10 months, veritable ancients for their world.

There’s no Business like Snow Business

I love snow. I still get excited every time I wake up in the winter to find fluffy flakes coating everything in white.

That first fall of snow every year is especially fun. It’s like the world has been dusted with fingerprint power. Suddenly, everywhere you look, the ground is littered with tracks and trails winding through the forest. Looking at all these footprints from the tiniest mouse to the big (but not necessarily bad) wolf, you realize there are a lot more critters in the forest than you were ever aware of.

I actually kind of miss it when all these signs melt away in the spring. It’s nice knowing that you’re not alone on those quiet walks through the woods.

I don’t really know if it’s true that the Inuit have 100 names for snow, but they do have several and we experience all of these different forms up here. There are two types in this picture alone.  The snow floating to the ground in fluffy flakes would be called anniu, and once it settles on the surface, you would call it api.

Unlike large parts of the country, we’ve only had light flurries since the first couple big snows this winter. Personally, I’d like a bit more. It would make snowshoeing more fun, but we had a lot of moisture in 2010 and the ground is already saturated. Unless we have a very slow melt this spring, we’re going to see a lot of flooding. Still, I just can’t help but wish for just a little bit more snow.