Farmed Mammals
Domesticated mammals are considered nongame because they are not wildlife --- they are farmed rather than hunted for food. Hunting privately owned farm animals is illegal under theft and poaching laws. Some hunters practice "penned hunting," in which a farm- or zoo-raised but ordinarily undomesticated animal is put in a high-fenced pen and shot. The ostensible reason some hunters prefer penned hunting is because the bagging of a "trophy" is virtually guaranteed. However, the practice is outlawed as inhumane in many places, including all Canadian provinces, except Saskatchewan and Quebec. Examples of mammals that are considered nongame because they've been domesticated are cows and horses. An example of a mammal which may be game in the wild but which is nongame when raised in captivity is the bear.
Companionate Mammals
Similarly to work- and farmed animals, mammals domesticated as pets and for companionship are considered nongame. In the United States, the federal Animal Welfare Act imposes limits on how people may treat companionate and domesticated animals that are involved in interstate commerce, such as animals that are transported across state lines or involved in scientific research. The federal Animal Welfare Act doesn't apply to the torture of an animal if the torture occurs within only one state. However, state laws do prohibit the torturing and killing of companionate animals. Examples of mammals that are considered nongame because hunting them is illegal under state animal welfare laws are dogs and cats.
Endangered and Threatened Mammals
Endangered and threatened animals are animals that are in danger of becoming extinct because of man's destruction of their habitat or through man's exploitation of the animal for sport pursuits, food or scientific research. It is illegal to hunt any animal --- including mammals --- listed on the Department of Environmental Protection's endangered and threatened species list. Since the mammals on those lists cannot be hunted, they are considered nongame mammals. Examples of endangered or threatened mammals include the Asian elephant, the gray wolf, the giant armadillo and the cheetah.
Mammals on Wildlife Refuges
Wildlife refuges are created in order to maintain threatened habitats, so they are usually home to a variety of endangered and threatened animals. While some game animals do live on the refuges, which animals are considered game is particular to the individual refuge and is subject to change as the animals' populations change. A mammal may be considered game one season and nongame the next. At all times, it is only legal to hunt on a refuge in designated areas and with proper licensing. Examples of mammals which may or may not qualify as game, particular to the individual refuge and season, are coyotes, squirrels and skunks. Some mammals which are endangered in their native habitat have overrun foreign wildlife refuges, so they are nongame in their native habitat and game in the refuges: one example of such a mammal is the Indian antelope, which is a nongame mammal in India and a game animal in Texas.