Breeding Behaviour

Male Display | Investigative | Aggressive | Sexual

Male Display Behaviour

The black curl of the penis of this male Arctic hare can be seen below its stomach.

David Gray's observations during the late winter breeding season at Sverdrup Pass on Ellesmere Island (April and May) are the first to document an unusual display-behaviour by male Arctic hares (Lepus arcticus). This behaviour marks the start of the Arctic hare's breeding season.

The display behaviour occurs at the end of a resting and grooming period. The behaviour follows grooming of the body fur. While the male stands with legs tensed, the long, slender, dark-coloured penis is uncoiled and stretched out along the belly, often extending out beyond the forelegs. This whip-like extension of the penis lasts about 1.5 seconds and is repeated up to 12 times in one bout.

David Gray first saw this behaviour in early April. It is most common in late April and early May. Later in the season it coincides with other breeding behaviours; it goes on until the mating season is over in late May. It happens within large groups of both sexes and also when a male is alone.

The Arctic hare standing third from the left is a male doing a penis diplay.

The function of this behaviour may be to visually stimulate females into breeding and receptivity. Male Arctic hares show increased interest in females before the females are actually receptive. Therefore, males must be reproductively active in order to initiate the breeding season. The male Arctic hare's display behaviour may be triggered by the increase in daylight in March (in the High Arctic, light levels steadily increase from December to April). The timing of the male display coincides with the time that breeding should commence in order for young hares to have time to sufficiently develop before winter.

The timing is another reason to think that something besides increasing light levels in spring stimulates female Arctic hares into receptivity, even though lengthening daylight stimulates some other female mammals (including some hare species) into receptivity. By the time the females need to be receptive, no further increase in the amount of daylight is possible because by mid April the sun is above the horizon for all 24 hours of the day.

The timing of receptivity, copulation and ovulation is important. (Ovulation is stimulated by copulation). All breeding needs to occur in a limited and specific time so that the young are born at the optimum time for adequate summer feeding and growth that will allow them to survive the coming winter.