Suzanne MacDonald, an associate professor of psychology and biology at York University, does research on all sorts of exotic creatures, including apes, lions and even the pandas at the Toronto Zoo. But her work on that infuriatingly ingenious masked urban pest, the raccoon, inevitably gets all the attention. For her current project, every few months she takes a baby scale and a measuring tape and writes down the weight and length of up to 20 frozen, dead raccoons, collected by city staff after run-ins with cars. The idea is to see if the new "raccoon-proof" green bins being gradually rolled out across the city are actually hitting the raccoon population where it counts: in the stomach. The Globe and Mail spoke with her as she went to work at a Toronto Animal Services facility in Etobicoke this week. Her heaviest weigh-in that day? A male measuring more than 10 kilograms.

What do you hope to find out by weighing and measuring frozen, dead raccoons?

I know this looks like a really weird thing to do. Maybe it is. But what I am trying to do is discover the body mass index of our urban raccoons. I think most of us in Toronto realize that we have fat raccoons. This is going to be a measure of the fatness of raccoons across time, as we roll out the new green bins across the city. The idea is that those raccoon-proof green bins will not be a source of food for these little guys any more. And if that's the case, we can see their body mass index reduce.

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You already have a pretty good idea that the new green bins are really tough for a raccoon to get into.

I tested the prototypes for the city. They just put them in my backyard and I just watched them for a week. I baited them with chickens from Loblaws, which are highly preferred, so all the raccoons in the neighbourhood wanted to get in. Not one ever got in, to any of the prototypes. The design of them is such that they can't knock them over. I have put cameras out in the areas where the [new] bins are that are adjacent to where the old bins are, and the raccoons try and then very quickly just move onto the old bins. They can't be their only source of food. The raccoons' territories are very small, three square blocks. So they are only getting those green bins once a week. They are not going to die en masse or anything. It's just that hopefully, they'll get thinner. And if they get thinner, they will have fewer babies.

The raccoons are fatter in the city. But are they smarter in the city, too?

My data have shown that there are differences between urban raccoons, our raccoons, and raccoons that live in the country like normal raccoons. I tested both populations over a period of a couple years, with a couple of tasks that they had to figure out to get food, problem-solving tasks. The urban ones were much more curious about things, like you would predict. And about 80 per cent of them figured out the harder task. The rural raccoons, zero of them figured out that harder task. It was a pretty striking difference. My hypothesis was that we are shaping the raccoons in the city, essentially making them smarter by making it harder for them to get food.

You also do research on the way elephants, chimpanzees and other animals think. How do raccoons compare?

It depends on the kind of intelligence you are talking about. Every animal is perfectly suited to its environment. Chimps, I think, people think are intelligent because they are like us. And they are, they are very similar. So we apparently are the gold standard for intelligence. I disagree with that, but certainly chimps are the most like us. I would say that raccoons are actually like other primates, like monkeys. If you look at India or other countries where monkeys are kind of around human habitation and they are getting in and stealing food and doing all that stuff, that's what raccoons do for us. So I really appreciate that I study other primates, and orangutans and gorillas at the zoo, and they're awesome. But I see a lot of primate-type behaviour in [raccoons], even though they are not primates. To me, the reason I am interested in them is because they are very smart.

This interview has been edited and condensed.