Ancestors of the muskox have survived since the Pleistocene Era, 10,000 years ago. With the retreat of the glacial ice, they spread through Northern Canada and Greenland, then westward into Alaska. Populations were strong since most people in the area harvested more caribou and fish for food than muskox.
By the 1900s, muskox populations in Canada had dropped significantly due to an increased interest in the trade of hides, hunting with guns, and several icy and harsh winters. In 1917, the Canadian government put the muskox under protection in the hopes of saving nearly extinct herds. In 1927, the Thelon Game Sanctuary was established to protect muskox on the tundra main land.
In the 1950s, muskox numbers dipped to a dangerous low of approximately 1,000 animals. To give the herds a chance to repopulate, even local residents stopped harvesting muskox. By the early 1970s, the number of muskox had increased significantly and the herds were once again viable.
Today, there are over 100,000 wild muskox roaming the mainland tundra and Arctic Islands of the NWT and Nunavut. In the winter they roam in isolated herds of approximately 75 animals. During mating season 15 to 20 cows will herd with one bull.
These herds are so successful that the number of grizzlies and wolves looking for food are increasing as well. For this reason, muskox have increased their range, roaming near the Northern communities in the area.