Aging a Red Fox Pup
There are several ways to estimate the relative age of a red fox pup, one of which is by noting the color of its coat. It is gray for their first month of life, when pups are in their den, sandy-colored for the next six to eight weeks, and red from about three months on. The color of the eyes of a red fox pup also tells you something about their age. For the first eight weeks of its life, a red fox has blue eyes. Around the age of two months, its eyes turn brown. All you have to do to utilize this knowledge is get within a few feet of a pup!
Frolicking Red Fox Pups
These red fox pups are roughly 7 to 8 weeks old…they’ve worked out sibling hierarchy, sampled solid food in the form of moles, squirrels, snakes and turkey and gone on short forays with their mother, but most of the day is spent tumbling with, pouncing on, chasing, biting and sitting on each other. Occasionally they stop long enough to take a nap. (Note the white toes!)
Red Fox Kits Nursing
When red fox kits are roughly five weeks old, not only do they begin spending time outside of their den, but they also start eating solid food and weaning begins. This mother is still nursing her young, but soon she will start discouraging them by not always giving them access to her milk through tactics such as lying on her stomach when they approach her for a meal. Within three weeks the kits will be completely weaned.
Naturally Curious with Mary Holland 
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