In the wild chinchillas have been known to live in large groups of 100 or more. With proper care, the life expectancy for a domestic chinchilla is about 15 years. Some have been known to live as long as 30 years.
Chinchillas are nocturnal so are at rest much of the day.
Their fur grows back, however, so this is nothing to be too concerned about. Chinchillas reach maturity at about eight to twelve months old and should not be bred until then. Gestation is generally 111 days. Females can become pregnant immediately following the birth of a litter. But these 'breed backs' are very draining and should only be allowed on a limited basis to females of excellent health.