Dispersal of Juvenile Fishers in Maine

We studied natal dispersal of fishers (Martes pennanti) in a harvested population in southcentral Maine during 1984-90 because of concern over the high level of harvest and a lack of information about fisher dispersal. Probability that an individual would disperse by the end of its first year was 73 and 100% for males and females, respectively (n = 21 M, 12 F). However, 32% of males and no females dispersed before the age of 9 months. Mean distance between natal and adult home ranges did not differ (t = 0.16, P = 0.88) between males (n = 8, x = 10.8 km, range = 4.1-19.5) and females (n = 5, x = 11.2 km, range = 5.0-18.9). Dispersal, in combination with intrasexual territoriality of adults, may limit fisher density and competition for food