The secret personalities of the red squirrels of Ashbridge’s Bay
My niece Lise has two black cats, Molly and Minou. They’re sisters Lise acquired when they were kittens. She raised them in the same home with the same routines and same food, but they couldn’t be more different. Molly looks like she’s hiding a watermelon in a waggly belly that almost touches the floor. She’s a fraidy-cat, a loner who prefers to hide all day under Lise’s bed. Minou, on the other hand, is a curious, gregarious cat that’s as sleek and slender as Molly is zaftig.
Two cats, two distinct personalities. We’re used to the idea of temperament in domestic animals. Is it a stretch to think wild animals could have personalities, as well? Could personality in wild animals be measured? And does it matter?
Alessio Mortelliti, a University of Maine wildlife ecologist, believes personality in wild animals can be assessed, and that it matters profoundly. He and some of his graduate students are studying the behaviour of small rodents in the Penobscot Experimental Forest in Maine; the university has produced a charming video to showcase their work, called “Small mammals, big personalities.”
“Like humans, animals have personalities,” Mortelliti says in the video. “There’s shyer mice, more aggressive mice, more curious mice, more active mice.”
Mortelliti says small mammals, like the cute woodland jumping mouse and American red squirrels his group studies, have a critical role to play in forest regulation and ecosystem composition. Behavioural and personality differences influence what type and size of seeds these animals eat. He’s seen squirrels spit out seeds they don’t like, seeds that can then go on to germinate and become a tree. Ultimately, such choices affect what tree species will be prevalent in the animal’s territory.
In a recent New York Times article, Mortelliti says that personality is found widely across the animal kingdom, citing five common personality traits: boldness, aggressiveness, activity, exploratory tendency and sociability.
When it comes to rodents, he says the winner of the contest for most aggressive is the American red squirrel, Tamiasciurus hudsonicus.
“They are incredible,” Mortelliti says of the agile little squirrels that look like they’re wearing cinnamon-coloured coats over starched white bibs. “They are the only species where you can conduct measurements on them, you release them, then they go up a tree and come towards you and yell at you. They really are a feisty, territorial individual.”
It is precisely because of the pluckiness of the red squirrel’s personality that I make a point of looking for them on walks at my local waterfront park, Ashbridge’s Bay. The park has enough coniferous tree species — including tamarack, European larch, Jack pine, Scots pine, Austrian pine and Norway spruce — to provide the cone seeds these squirrels prefer.
The little rodents are not always easy to find, though. Unlike the park’s eastern grey squirrels, which scamper toward strollers to seek handouts of peanuts and other treats, the red squirrels are skittish and easily alarmed. When I do see one, it’s usually because I’ve noticed cones raining down. When I look up to see what gives, there’s a red squirrel perched high in the branches of a larch, methodically stripping seeds from its cones, then tossing the empty husks overboard in rapid succession.
On the rarish occasions I do make eye contact with a red squirrel, it fixes me firmly with a schoolmarm stare, its black eyes shining bright as buttons behind crisp white specs. If alarmed or defending its territory, it will make a rapid, chattering rattle that goes on and on, leaving no room for dispute. This species is feisty, and then some.
Recently at Ashbridge’s, though, I’ve come across a red squirrel I’ve dubbed Hudson that seems to be behaving differently. Hudson seems bolder and willing to take bigger risks on the ground. Early in March, I found Hudson searching for food among the mouldering leaves. Rather than skedaddling full speed up the nearest tree, he allowed my slow, quiet approach.
A few days later, I saw Hudson competing with a flock of noisy mallards for an easy meal. The ducks were taking turns jumping onto a rock where passersby had left generous handfuls of birdseed. Brave little squirrel, going nose to beak with the mallards!
I wondered if this was a behavioural change or personality difference in this particular squirrel. These rodents have plenty of predators in the park, including off-leash dogs, minks, foxes, owls and hawks. Would Hudson’s boldness ultimately work in his favour? Or would such risk-taking lead to his early demise?
Allison Brehm, one of Mortelitti’s grad students featured in the U of M video, says animal populations need diversity of personality to stay healthy.
“A population with all the same behavioural type is not going to be able to withstand change as well as a population with all sorts of behavioural types,” she says. “A bold mouse might have advantages in some situations but a shy mouse may also have advantages in some circumstances.”
That’s true for red squirrels, too. As research continues in animal personality and ecosystem health, these mettlesome mammals in our neighbourhood parks give us the opportunity to observe the behavioural differences of wild animals in action.