Cute Hamsters

Reproduction
Hamsters become fertile at different ages depending on their species, but this can be from one month to three months of age. The female’s reproductive life only lasts about 18 months, but male hamsters remain fertile much longer. Females are in heat approximately every four days, indicated by a reddening of genital areas.
Hamsters are seasonal breeders. Breeding season is from April to October in the northern hemisphere, with two to five litters of 1 to 13 young being born after a gestation period of 16 to 23 days. Gestation lasts 16 to 18 days for Golden Hamsters, 18 to 21 days for the Russian hamsters, 21 to 23 days for Chinese hamsters and 23 to 30 for Roborovski Hamsters. The average litter for Golden Hamsters is about 7, but can be as great as 24, which is the maximum number of pups that can be contained in the uterus. Campbell's Dwarf Hamsters tend to have 4 to 8 in a litter but can have up to 14. Djungarian Hamsters tend to have slightly smaller litters, as do Chinese and Roborovski hamsters.
Chinese hamster females are known for being aggressive toward the male if kept together for too long. In some cases, male Chinese hamsters can die after being attacked by the female. If breeding Chinese hamsters, it is recommended to separate the pair after mating or the hamsters will attack each other.