Monestrous, with 76% breeding in mid-January to mid-February; 53% occurs between 0500 - 1000 hrs and 20% from 2200 - 0100 hours. Males are considered monogamous by nature, but hunts alone and lives together only to raise young. Gestation is 51 - 52 days; greater than 13 year life span is normal. This is the only rabies reservoir currently in Europe. Raw carp causes Chastek's paralysis. Five to six pups per litter, born brown/gray, turning reddish at about four weeks. Tail called brush. Doubles back on its tracks to outwit enemy.