COUGAR POPULATION-DYNAMICS IN SOUTHERN UTAH

We monitored size and composition of a southern Utah cougar (Felis con color) population during 1979-87 to document the dynamics of this unhu nted population and to test the hypothesis that cougars would regulate their density at a level below that set by prey abundance alone (Seid ensticker et al. 1973). We captured cougars when detected during ongoi ng searches for sign in the study area. Resident adult cougar density remained relatively constant (0.37/100 km2) for the first 7 years but increased slightly in the last 2 years. Mule deer (Odocoileus hemionus ), the cougar's primary prey, increased over the 9 years, but magnitud e of this increase was unknown. Results supported the hypothesis that cougar density is set by environmental features other than prey abunda nce alone. Adult resident females bred as young as 17 months and produ ced litters that averaged 2.4 kittens at an interval of 24.3 months.