structural:expansion
Diet

Like all land mammals that are pack hunters, the wolf feeds predominantly on ungulates that can be divided into large size 240–650 kg (530–1,430 lb) and medium size 23–130 kg (51–287 lb), and have a body mass similar to that of the combined mass of the pack members. The wolf specializes in preying on the vulnerable individuals of large prey, with a pack of 15 able to bring down an adult moose. The variation in diet between wolves living on different continents is based on the variety of hoofed mammals and of available smaller and domesticated prey.

In North America, the wolf's diet is dominated by wild large hoofed mammals (ungulates) and medium-sized mammals. In Asia and Europe, their diet is dominated by wild medium-sized hoofed mammals and domestic species. The wolf depends on wild species, and if these are not readily available, as in Asia, the wolf is more reliant on domestic species. Across Eurasia, wolves prey mostly on moose, red deer, roe deer and wild boar. In North America, important range-wide prey are elk, moose, caribou, white-tailed deer and mule deer. Prior to their extirpation from North America, wild horses were among the most frequently consumed prey of North American wolves. Wolves can digest their meal in a few hours and can feed several times in one day, making quick use of large quantities of meat. A well-fed wolf stores fat under the skin, around the heart, intestines, kidneys, and bone marrow, particularly during the autumn and winter.

Nonetheless, wolves are not fussy eaters. Smaller-sized animals that may supplement their diet include rodents, hares, insectivores and smaller carnivores. They frequently eat waterfowl and their eggs. When such foods are insufficient, they prey on lizards, snakes, frogs, and large insects when available. Wolves in some areas may consume fish and even marine life. Wolves also consume some plant material. In Europe, they eat apples, pears, figs, melons, berries and cherries. In North America, wolves eat blueberries and raspberries. They also eat grass, which may provide some vitamins, but is most likely used mainly to induce vomiting to rid themselves of intestinal parasites or long guard hairs. They are known to eat the berries of mountain-ash, lily of the valley, bilberries, cowberries, European black nightshade, grain crops, and the shoots of reeds.

In times of scarcity, wolves will readily eat carrion. In Eurasian areas with dense human activity, many wolf populations are forced to subsist largely on livestock and garbage. As prey in North America continue to occupy suitable habitats with low human density, North American wolves eat livestock and garbage only in dire circumstances. Cannibalism is not uncommon in wolves during harsh winters, when packs often attack weak or injured wolves and may eat the bodies of dead pack members.