Hungary's Budapest Zoo is home to a large family of breeding Prairie Dogs. These pictures are a mashup of this year's litter as well as last year's. Prairie Dog "towns" can be easily identified by the large mounds of dirt which contain their tunnelled homes beneath. According to the San Diego Zoo, when a female Prairie Dog is ready to give birth, she goes to the nursery burrow. The young, called pups, are born hairless and with eyes closed. In the nursery, the mother will take care of her pups until they are about six weeks old and ready to venture aboveground. At about one year of age, the young Prairie Dog may leave to start a new coterie by taking over abandoned tunnels or by digging new ones.