Spatial and Social stability of a Eurasian lynx Lynx lynx population: an assessment of 10 years of observation in the Jura Mountains

A total of 18 Eurasian lynx Lynx lynx were radio‐tagged between March 1988 and June 1998 in the Swiss Jura Mountains, and during 1995‐1997 eight animals were radio‐tagged on the French side of the mountain chain. Adult males occupied larger long‐term home ranges than adult females (283 km 2 vs 185 km 2 ). Neighbouring males shared 7.3% of their home ranges and females 0.2%. The mean distance between males and females living in the same area for fixes taken the same day was 10.94 ± 8.61 km, underlining the solitary character of the species. Consecutive individual annual home ranges overlapped 71.7 ± 7.3% for females and 77.5 ± 7.9% for males, indicating high spatial stability over time. In the Swiss study area, two adult animals were followed for seven and nine years, respectively, and another two lynx were observed in the study area for nine years. Range size did not vary across three distinct periods, P1‐P3, but the sex ratio did. Generally, males covered the ranges of 1‐2 females, but during the second period, P2, the range of a single male overlapped with those of six females. Dead females were all immediately replaced, but dead males were not. Two poached males were only replaced after three and five years, respectively. Population density, ranging within 0.7‐0.8 adult resident lynx/100 km 2 , did not vary significantly over time in Switzerland. Including kittens and subadults, the density was 1.1‐1.6 lynx/100 km 2 . Our study in the Jura Mountains indicated that there is long‐term stability in the social and spatial structure of the lynx population, but this stability was temporarily disturbed by the lack of adult resident males.