Natal Dispersal of Snowshoe Hares during a Cyclic Population Increase

We used radiotelemetry to monitor movements of 35 juvenile snowshoe hares (Lepus amer-icanus) from weaning until their first breeding season (June 1995–April 1996). Juveniles born on control or food-addition areas were assigned to one of three cohorts of litters. We calculated natal dispersal distances (distance from nest site to breeding location) and frequencies of emigration (proportion dispersing more than twice the home-range diameter of adults) and determined ages and dates at emigration. Natal dispersal distances ranged from 23 m to > 16 km. Fifty percent (9/18) of juveniles that survived until their first breeding season emigrated. Juveniles from the third litter dispersed at an older age than those from first or second litters. We detected no statistically significant effect of food addition on dispersal distance. With our small sample, we did not find statistical evidence of sex-biased natal dispersal (7 of 12 males and 2 of 6 females dispersed).