INFLUENCE OF FOOD AVAILABILITY AND REPRODUCTIVE STATUS ON THE DIET AND BODY CONDITION OF THE EUROPEAN LYNX IN FINLAND

The carcasses of the 497 European lynx Lynx lynx (Linnaeus, 1758) killed in two areas in Finland in the 1980s were sexed, the nutritional status and diet of the lynx determined and the breeding stage of the females checked. There was no significant deviation in the sex ratio from 50:50 in any of ten hunting seasons. Fifty-three percent of the females over 1 year of age had given birth the previous spring, the mean litter size from the last pregnancy being 2.33 +/- 0.73 ((x) over bar +/- SD, n = 82). In E Finland 86.2% of the winter diet consisted of hares, whereas in SW Finland the lynx consumed hares and white-tailed deer equally. There was no difference in diet between the sexes or age categories in E Finland, but in the white-tailed deer area of SW Finland the male lynx consumed more deer and hares less frequently than the females (p < 0.05). The lynx in SW Finland were on average, in a much better nutritional condition than those of E Finland. The male lynx in both areas had gained more depot fat than the females, on average a difference arising primarily from the smaller amount of fat in the female lynx which had given birth the previous spring. There were positive correlations in E Finland in all the age and sex categories between hare density and mesentery-omentum fat whereas snow depth produced negative correlation coefficients with the mesentery-omentum fat showing a significance of 90% in the adult females.