Q. Squirrels are scurrying around hiding food. How do they locate these buried items, especially when snow covers the ground?
A. Mainly by nose, said Scott Craven, emeritus professor of wildlife ecology at UW-Madison. "The consensus among scientists is that the gray squirrel uses its sense of smell, even through deep snow."
The gray squirrel that's common in the Madison area will "bury nuts seemingly willy-nilly across the landscape and then return by the sense of smell," Craven said, although they may also use other cues. In contrast, the territorial red squirrel, which lives further north in Wisconsin, stores large caches of food and seems to remember the location.
Gray squirrels are quite efficient at finding nuts, Craven said. When scientists built a cage to exclude gray squirrels and buried some nuts inside the cage, the gray squirrels that later entered the cage found 85 percent of the nuts. "They are pretty darn good at it, even when they did not bury the nuts," Craven said. "They don't just find their own nuts; it's essentially a community good. Unless there is some scent cue related to the individual squirrel, they are likely to be finding nuts they or some other squirrel buried."
It's a good thing that squirrels are not perfect at retrieval, Craven added, "because seed burial is the primary means of reproduction for many seed-bearing trees, including the oaks."
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