All across the boreal forests of Canada, wolves look for the same things: clean water, safe dens, and places where deer or moose are plentiful. When wolves find everything they need in one area, they establish a territory, and that’s where they stay.
The idea of wolves as territorial has been part of scientific dogma (ha! DOGma!) for so long that, when I submitted my first scientific paper on the genetics of migratory wolves on the Arctic tundra, the journal refused to print it. Indigenous people in the Arctic knew wolves migrated, but scientists had never measured those movements… which meant the scientists reviewing my paper thought I was making it up.
Fortunately, we’ve made some progress since then, and a lot of scientists now recognize that the Traditional Ecological Knowledge of Indigenous peoples around the world is often based on exactly the same kinds of empirical observations used to produce scientific knowledge… meaning it’s just as reliable.
But back to the wolves. What about the Arctic tundra makes wolves migratory?
The Arctic tundra is often called the barren-grounds, because it’s so cold and dry that trees don’t grow. Deer and moose don’t like to live in places without tasty trees, but barren-ground caribou do just fine on the tundra. These caribou form herds that may contain thousands of animals, and females have their babies in traditional areas called calving grounds.
Arctic wolves make their dens as close to the calving grounds as they can. Adult wolves visit the nearby calving grounds, catching caribou and bringing meat back to their pups. But in the autumn, the caribou leave the calving grounds and migrate south to the boreal forest, where there’s more food and shelter in winter. The wolves have to follow, because if they stayed in their denning territories, there’d be nothing left to eat.
As with pretty much everything in science (and in life), there are exceptions! Wolves that stay on the tundra year round have to switch to other kinds of prey: for example, muskoxen, which are bigger, meaner, and harder to bring down than caribou. Wolves will also hunt smaller prey like arctic hares or foxes, but in general, a wolf pack needs large hoofed mammals to survive.
When pickings are slim, wolves receive help from a surprising source – ravens! Ravens that find caribou kick up a fuss, drawing wolves to the prey. Ravens will also lead wolves to carcasses of animals that have died naturally. Raven beaks aren’t strong enough to cut through skin, but wolf teeth are… and the ravens get the leftovers. A relationship like this one, where both species benefit, is called mutualism. Cooperating helps both wolves and ravens survive long arctic winters.
If you’re interested in learning more about the forest, the tundra, or the animals that live there, check out my books The Boreal Forest and Polar: Wildlife at the Ends of the Earth. Happy World Wildlife Day!
I’m also scheduling a number of book launch events that will be open to the public. Click here for the full schedule – I’d love to see you!