The Picky Mouse Club

Some mice shop for a new home much the way people do: they repeatedly visit several nest sites before deciding on one.

After being weaned, brush mice (Peromyscus boylii), which live throughout western North America, venture forth from their birthplaces to find living quarters of their own.

Wondering just how the mice go about choosing their lodgings, Karen E. Mabry and her graduate adviser at the University of California, Davis, Judy A. Stamps, followed the movements of thirty-one juveniles fitted with tiny radio collars in a university nature reserve.

Noting where the nocturnal rodents slept during the day for the week or more they spent nest hunting, the two biologists discovered that the mice visited an average of three potential nest sites before finally picking a permanent home.

Notably, individual mice often revisited potential nests, and didn't necessarily pick the last one they visited.

Thus they appeared to be comparing the suitability of various possible homes, rather than settling for the first nominally acceptable one. Many animals are known to employ a similar strategy when choosing mates — another important life decision — but this is the first time comparison shopping for a home by a mammal has been demonstrated in the field.

The research was detailed in The American Naturalist.

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