Fecundity of Female Wolverine in Montana

Abstract

We collected carcasses from trapper-harvested wol\erine (Gulv gulo) in Montana from 1984 through 2005 lo evaluate pregnancy rates and corpora lutea proc.Juct1on as an estimate of wolverine fecundity in eco-regions and subpopulations of western Montana. Pregnancy rates 111 the northwest eco-region were I 00 percent for adults (n=11) and 30 percent for subadults ( 11 = 15). Pregnancy rates within the southwest cco-region were less than obsened 111 the nortlrnest (67.8 % for adults, n = 28; and 12.5 % for subadults, n=16). We observcc.J similar 1esults in subpopulations from northwestern and southwestern Montana Median corpora lutea counts for pooled adult and subadult females also differed among eco-rcg1ons being g1cater in nortlml:st (median = 3.0, n = 26) than the southwest (median = 0.0, 11 = 44 ). Litter <;I/es; and m1:asun:ment of recovered fetuses are also presented. Comparisons of our data to similar studies in North America suggested adult pregnancy rates and mean litter sizes observed in the soutlw.:estern eco-region of our study area are the lowest reported in the literature.