Breeding & Mating
Chinchillas become sexually mature when they are around eight months old. They mate seasonally based upon the light cycle. In the northern hemisphere, mating season takes place from about November until May.
When the female is receptive to mating, the male initiates by grooming the female and will attempt to mount her. Multiple quick matings may occur over a period of time. Sometimes the female can become aggressive and attack the male. Injury is possible, so mating chinchillas should be supervised for their safety.
Pregnancy & Babies
Chinchillas have a long pregnancy and the gestation period is around 110 days. Birth usually occurs in the morning and the babies, known as kits, are born a few minutes apart. The kits are born with their eyes open, covered in fur, and weigh around 2 ounces. They are active and can run and play from birth. Litter size is small with usually only two babies born, but there can be as many as six.
A mother is very protective of her kits and can be aggressive toward those that threaten her babies. She is an excellent parent who supplies the young chinchillas with milk, warmth, and protection. Some males can be good fathers, but others can be aggressive to the kits and even try to kill them.
Babies will eat solid food after about a week, but are still dependent on their mother and her milk for up to 8 weeks. After they are weaned, the young chinchillas are ready to be moved to a new home.
To sex a chinchilla, hold it belly up and check by the anus. Males have a patch of bare skin between the anus and urethral opening. Females have a small slit opening and no patch of bare skin. The distance between the urethral opening and anus is much further apart with males compared to females.