Are there any clues to determining the age of a hamster once it is fully grown? I work in a pet rescue, and we are frequently asked as to how long our adult hamsters might live, but we often don't know their age in the first place.

Older hamsterThis can be an issue, because hamsters are quite short-lived pets, with a maximum life expectancy of typically no more than three years. Parents are obviously concerned that if they acquire a hamster of uncertain age for their child, they could end up with the trauma of losing it from old age within a few months. 

Unfortunately though, there are no clear pointers that you can use, to give a precise age. But once the fur shows signs of thinning, and the hamster is less agile and active than is normal, then the chances are that this individual will be getting elderly.