Bears
Several species of bear prey on moose. The North America grizzly bear is one of a few animals large enough to kill a fully grown adult moose. The grizzly bear preys on moose during the late winter. Moose move slower in the winter due to snow; a grizzly bear will attack a moose that has left its den looking for food in the snow. Also, the black bear is another predator. The black bear, which is smaller than a grizzly, preys on newborn and young moose because of their more manageable size.
Wolves
Wolves are another species of animal that hunts the moose. Timber wolves prey on calves that have been separated from their mother. They also attack vulnerable moose that are either sick or disabled. A moose will defend itself from a wolf attack by charging or kicking with its powerful hooves. However, a pack of wolves can kill a moose, especially a female with calves. A group of more than four or five wolves can lead an organized attack by grabbing the moose's nose, rump or hocks.
Scavengers
There aren't many animals capable of killing a moose. Most moose die from disease or old age. When they die, many smaller animals prey on the carcass; the flesh, hair and bones are consumed by other organisms. These include foxes, ravens, wolverines and eagles.
Other Threats
Moose live in North America in the same habitat as white-tailed deer. Moose disease is transmitted by white-tailed deer and is fatal to moose; it is caused by a parasitic roundworm that invades the brain. Another serious predator for the moose is man. Humans over-hunting moose decreased the population in the wild. Other animals known to eat moose include killer whales and cougars.