Fall Reveals The Squirrels’ World
Lucas is at the window pointing at a squirrel making its way headfirst down the tree outside.
He loves squirrels and has his whole life. He just turned three and every time I look at him I wonder at how fast he has grown. My baby is a boy. He barely has that baby lisp anymore – a good thing, I know – but I love that he still can’t quite say ‘squirrel.’
“How does it climb down the tree like that?” My eldest son, Ray, joins us at the window.
Turns out that squirrels have super flexible ankle joints. When a squirrel wants to climb down headfirst, it rotates its hind feet 180 degrees. Just imagine twisting your feet around till they were pointing backwards! With its back feet rotated, the squirrel can dig its claws into the tree trunk and hang from its back legs.
The squirrel climbing down our tree was an Eastern Grey Squirrel, far and away the most common squirrel in Toronto. Now if you’re thinking, “Wait a minute our squirrels aren’t grey — they’re black!” you are absolutely right. Eastern Grey Squirrels are very variable in colour and the black (melanistic) morph is common in southeastern Canada, especially in urban areas where squirrels have fewer predators.
“It sure is collecting lots of food,” says Ray.
Squirrels prepare for winter by gathering food during times of plenty. They hide this food in small caches for later access. Squirrels use their memory to lead them back to the approximate location of a cache and then their keen sense of smell to find the exact spot. Each squirrel is estimated to make several thousand caches each season! (And I swear hundreds of them are in my garden.)
Often these food caches consist of plant seeds, like acorns. The good news is that this behavior makes squirrels seed dispersers because the stores are often either forgotten, or just not needed, so the seeds are left buried and may germinate.
“Do squirrels hibernate, like bears?” At nearly six, Ray is learning about hibernation at school, and watching the squirrel gather food and eat like crazy is enough to make anyone wonder.
Tree squirrels, like Eastern Grey Squirrels, do not hibernate. Instead tree squirrels survive the cold winter by growing longer and thicker fur. Like humans, they also stay inside more in winter, so we see them less. They stay warm either in tree cavities or in nests, called dreys. Other members of the squirrel (Sciuridae) family especially those that live in burrows underground, like chipmunks, do hibernate.Tree cavities are preferred in winter because they offer better protection from the cold but where tree cavities are in short supply, dreys are used. You’ve probably seen squirrel dreys, though you may have thought they were bird’s nests, as I once did.
Squirrels make their dreys by gnawing off tree branches that they weave into a hollow sphere with a single entrance hole, usually facing the tree trunk. The leaves attached to these branches go brown in winter, but they do not fall because the branches were collected before the tree began the process of shutting down and dropping leaves. This outer layer of leaves helps to make the nest water resistant. The inside of the drey is lined with softer materials such as grass, moss, leaves, shredded bark and pine needles, which insulates against cold.Although squirrels build their dreys in summer or early fall, we don’t usually see them until later in the season. As the leaves fall, the world of squirrel dreys is revealed. Although they are much loved by my kids — and many adults too — squirrels can be pests! We have a veritable army of them in our backyard. They eat our tomatoes before they can ripen, dig up our carrots, snap the heads off marigolds and even eat neighbourhood Jack-o-Lanterns at Halloween!
And they can cause much bigger trouble than that. As Jon Mooalem describes in this article in the New York Times, squirrels are a major cause of power outages, some massive. Just think of it: one small rodent can literally wreck havoc in the lives of thousands of people – but of course the squirrel itself suffers most.
Love them or hate them, squirrels are all around us in our wild city. And the Ontario Ministry of Natural Resources has some great tips for living with them in relative peace.