The snow leopard lifespan for females, on average and in captivity, is 9.6 years (Ref: O’Connor T and H Freeman 1982 Maternal behaviour a behavioural developments in the captive snow leopard (Panthera u. uncial). International pedigree book of snow leopards 3: 103-110).
However, a female snow leopard in the Cheyenne Mountain Zoo, Colorado gave birth to a litter of cubs at the age of eighteen years.
In general, snow leopards in captivity have lived to up to 21 years of age. (Ref: Wharton D and H Freeman 1988. The snow leopard in North America: Captive breeding under the Species Survival Plan. In Proceedings of the fifth international snow leopard symposium, ed. H Freeman, 131-136. Bombay: International Snow Leopard Trust and Wildlife Institute of India).
The Snow Leopard Trust say they can live up to 22 years in captivity. This implies that snow leopards appear to do well in captivity. Not all wild cats do. Some small wild cats have relatively short lives in captivity due to stress. The snow leopard is considered to be less fearful of humans than most of the wild cat species which may be a factor but they do have enormous home ranges which could make confinement stressful.
The Snow Leopard Trust (the premier source for information on the conservation of this cat) also say that in the wild their lifespan is shortened considerably to around 10-12 years.
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