Abstract: Eight adult pairs of snow leopards (Panthera uncia) were observed for one to three years in the months December through March to determine the species' social and reproductive characteristics in captivity. To statistically examine the occurrence of behaviors as a function of estrus, the observation weeks were divided into three time blocks: before estrus, estrus, and after estrus. Using percentage of scan samples as an estimate of time spent in various behaviors, 16 behaviors and combined behavior categories were examined for (1) behaviors that differentiated successfully from unsuccessfully breeding pairs, (2) sex differences in behavior, (3) significant correlations between pair members, and (4) behaviors that showed time block effects. The rationale for identifying a behavioral profile of successful breeders in snow leopards was to aid zoos in their captive management programs by increasing their knowledge of the social behavior of this species. By finding correlates to breeding success, informed decisions on whether to change partners after a certain period of time, how to group the cats, and the optimum strategy for a survival plan can be made. (PsycINFO Database Record (c) 2000 APA, all rights reserved

Abstract: Serum oestradiol and progesterone concentrations were measured at weekly intervals for six months, and correlated with daily behavioural observations in two adult female snow leopards (Panthera uncia). Three oestradiol peaks (> 21 pg ml-1; interval 3.6 weeks) were identified in a snow leopardess housed alone (two more were probably missed because of the weekly sampling schedule), and three oestradiol peaks were identified in a snow leopardess housed with a male as a breeding pair (interval 6 weeks). Daily frequencies of feline reproductive behaviour averaged 1.77 observations per observation period during weeks of high oestradiol and 0.62 during weeks of low oestradiol. Progesterone concentrations did not rise above baseline values (< 2 ng ml-1) in the isolated animal, but 6 weeks of high progesterone concentrations (4.9- 38.8 ng ml-1) was recorded in the paired snow leopardess following mating. No offspring were produced. Snow leopards were observed daily for an additional 4.5 years. Sexual behaviour peaks could be clearly identified from December through April, and average daily sexual behaviour scores were higher during these months than during the rest of the year. Intervals between sexual behaviour peaks for the isolated snow leopardess averaged 3.03 weeks. The sexual behaviour of the paired snow leopards decreased for 8-9 weeks following mating when no offspring were produced, and decreased for 13 weeks in one year when a single cub was born.