Life Cycle

Growing Up | Mortality | A Year in the Life

Growing Up

Young hares are called leverets. In the High Arctic, Arctic hares (Lepus arcticus) are born in June with an average litter containing five leverets. In Newfoundland they are also born in June but the average litter size is three leverets. Arctic hares are born in the open, with no shelter except a shallow depression on the tundra. The young are born with fur, which is greyish-brown and blends into the surroundings.

Though the mother is attentive and remains close to her young just after birth, she soon restricts her visits to a brief one each day. She will visit them in order to nurse them and she will do so once every 18 to 19 hours, for the rest of the summer. The schedule is so precise that David Gray's research team could plan in advance when to visit a nursing spot in order to be sure to see the nursing event. The young also know exactly when to show up, even though the appointed time changes every day. Talk about a 'biological clock'!

A newborn Arctic hare.

Young Arctic hares huddling together.

As young hares grow, they begin to leave the nursing site for short periods. A short time before the next feeding, they will group together at the nursing site and huddle together before the mother arrives. At first they will huddle together for about an hour in advance, but the time spent huddled together decreases as they age.

Young hares are weaned abruptly in late August, but they continue to feed and rest together at least into September. In areas with large populations, the young from different litters sometimes gather into large groups. They develop rapidly and by late autumn are almost indistinguishable from the adults. We do not know if the young hares take part in the spring breeding in their first year, or if they reach sexual maturity only in time for their second spring.

Mortality

How long do wild Arctic hares live? We don't really know. (We do know that the European hare, Lepus europaeus, lives for a maximum of about 4 to 5 years in the wild). An adult male hare that was tagged in July 1986 by David Gray's research team at Sverdrup Pass on Ellesmere Island was still alive in August 1990. If the hare had been born in the spring of 1985 (the latest time possible), he would have been five years old in 1990.

Although predation is probably the main cause of death, Arctic hares also may die in other ways. Though disease does not normally seem to be a factor and Arctic animals are relatively free of diseases, in times of stress and high populations disease may become more widespread. Arctic hares do suffer injuries during certain social encounters and these injuries may, on occasion, lead to death through weakness or infection. In the mountains, rock falls or glacial ice falls may occasionally kill hares.