The chipmunks in your yard might be healthier and happier than their counterparts in rural areas, says a Laurentian University researcher.

Albrecht Schulte-Hostedde, a Canada Research Chair in applied evolutionary ecology, said his recent paper published in Oxford University's Behavioural Ecology, suggests that chipmunks in the city live a surprisingly different life than their relatives in the country.

"We expected chipmunks that lived in the city would be more stressed out, probably thinner," Schulte-Hostedde said.

"What we found was that chipmunks that live in the city are fat...and they have relatively low stress hormone levels compared to their counterparts in natural habitats."

City chipmunks also spend more time grooming and less time moving around, Schulte-Hostedde said.

The research team studied chipmunks in Sudbury, an area on the outskirts of the city, Hunstville, and in Algonquin Park for a couple of years.

The data shows that not only are chipmunks surviving the loss of their natural habitat, they're thriving.


Shulte-Hostedde's team measured the mass of each chipmunk, eventually finding that city chipmunks carry a little more weight. (Albrecht Shulte-Hostedde)

Urbanization and the eastern chipmunk

The findings are important, Schulte-Hostedde said, because urbanization is creating more conflicts between humans and wildlife, and the consequences should be measured over time.

"In some cases it's bad for wildlife...some species are going extinct or population is being reduced," he said. "In the case of chipmunks...they're common, but what is the consequence of urban living for these animals?"

"We know it's altering their physiology...or in the cases of chipmunks it's causing them to be heavier, we know they're gaining fat because of access to [food.]"

Albrecht Shulte-Hostedde

Albrecht Shulte-Hostedde is a Canada Research Chair of Applied Evolutionary Ecology at Laurentian University. He is also the director of Centre for Evolutionary Ecology and Ethical Conservation. (Albrecht Shulte-Hostedde)

Shulte-Hostedde said the next step would be to look for evolutionary changes in species that become accustomed to urban living, and to measure those changes against their relatives in less-urban areas.

"Do we see that chipmunks in urban habitats, the ones that are heavier.. the ones in particular that have lower cortisol levels? Are we seeing that they have enhanced reproductive fitness?"

"Are they producing more offspring? Are they surviving longer period of time?"

"We also want to know what is the nutritional ecology associated with these animals?" he said.  "What are the physical consequences of eating muffin bottoms and pizza crusts?"