Herbivores on the tundra include the Arctic hare, lemming, muskox, and caribou. Other game includes narwhal, polar bear, wolverine and muskox. In northern Alaska, grizzly bears often encounter muskox. Other big game existed at the time such as caribou and muskox. The muskox is confined to the arctic tundra. The takin was previously considered closely related to the Arctic muskox. Attempts to introduce the Arctic hare and the muskox have both failed. The burrows are lined with lichens, leaves, and muskox hair. The muskox hunt was filmed just outside Hughenden, Alberta. In September 2010 the muskox was reintroduced. They make nests out of grasses, feathers, and muskox wool (qiviut). The muskox sheds this layer of wool each spring. The project continues at the muskox farm in Palmer, Alaska. Qiviut is the fine underwool of the muskox. An adult muskox can produce of qiviut a year.