The Canada Jay lives year-round in northern North American forests and stores food in trees for colder periods. Its round head, long tail, and gray-and-white plumage make it distinctive.
Adults have a stocky body, round head, short stout bill, and long tail. They are darker gray above and lighter gray below, with a dark patch on the back of the head.
Canada Jays hide food in summer and autumn, then draw on these caches through winter. At Algonquin Provincial Park in Ontario, researchers followed a marked population near the southern edge of the species’ range. Sutton and colleagues compared local weather data with breeding records from 718 nests monitored between 1977 and 2016.
In years with more autumn freeze–thaw events, the study recorded smaller broods, lower nest success and poorer nestling condition the following late winter. The authors suggest that repeated freezing and thawing may reduce the amount or quality of stored food. The results connect a specific autumn weather pattern with several measures of reproduction in this food-caching bird.
An extinction-risk assessment has not been added yet.
At this southern-edge study site, years with more autumn freeze–thaw events were associated with lower brood size, nest success and nestling condition. The authors warn that future increases may threaten Canada Jays and other species that store perishable food for long periods.