In 1986, mean clutch size was 7.7, with an average of 7.0 eggs hatching and 3.4 young per nest fledging. The short-eared owl is well adapted to heat and cold. Short-eared owl populations at the edge of the species' northern distribution move south in late summer or early fall, but it is unclear whether more southerly populations migrate or remain in an area as permanent residents. Banding records are few, but limited studies show that some individuals in populations south of taiga are regular migrants. Others are irregular migrants, leaving in some years but not others.
Some owls probably migrate to new areas as young adults, then become permanent residents.
Migration routes are generally north-south, but not always. Except for populations at climatic extremes, when entire populations migrate it is usually in response to depletion of the prey base rather than seasonal climate changes. Longevity - Captive birds have lived to age 15. Short-eared owl occupy a variety of open habitats within their wide geographical distribution. They are the only North American owl that habitually build their own nest each year.