ENHS Nature Trails April 2004 Article 3

Musk Ox
by Reida Kimmel

The sight of approximately thirty, rather elderly, and thus often stiff and portly persons dressed in many layers of technology's finest winter wear and high rubber boots, slinking, slithering and, yes, crawling, along the rocky tundra, could have inspired gales of laughter except that the object of the expedition was to very quietly sneak up on a summer herd of six muskoxen grazing on sedges in the dusty plain below us. We got quite close, and lay in the warm sun for several hours just watching these remarkable animals. What did they do? Why they pawed the ground. They lay down and got up. They grazed, and the bull courted one cow, sniffing her, raising his lip to test the scent just as a ram or a stallion does. The bull then repeatedly rubbed the cow's side, pawed her shoulder with his foreleg, and as she continued to stand, mounted her. We were lucky to see a breeding event, as the season was nearly over. Surely the herd was aware of our presence. We did shift about quite a bit, but they remained calm. Their placidity seemed odd, because the muskoxen of Jameson Land on the north side of Scoresby Sund are hunted by the native people who killed one hundred thirty of them this year.

I spoke of cows and the bull, but these animals are not cattle. Ovibos moschatus is the single surviving species of a genus that evolved in Siberia and thrived all over Eurasia and North America, as far south as New Jersey during the Ice Ages. Its closest relative is the takin, a ruminant of Tibet, and more distant relatives include the chamois and the Rocky Mountain goat.

Muskoxen are really special and they are beautiful, with broad spreading horns, big dark eyes and glorious brown and amber coats. They are exquisitely adapted to the unbelievably harsh climate of the Arctic from northern Alaska to Greenland. To help maintain their constant body temperature of 101 degrees, their bodies are clothed in a dense, downy undercoat, softer and far warmer than wool, and this undercoat is covered, in adults, by a thick and very long coat of glossy guard hairs which reaches below the knees. The texture of the long guard hairs is like that of a horse's tail, but appears to be much shinier. The undercoat is shed every summer and is used by birds for nests, and in Alaska, collected and spun into the luxury fiber quiviet. (I collected a little myself, but have yet to spin it.)

The eyes of muskoxen are unique. The retina is adapted to enhance vision in low light, and the pupil, a horizontal slit, can contract to prevent snow blindness. The pupil is also, even more than a horse's eye, densely lined with corpora nigra, which protects the eye from the glare of ice, snow and the summer sun. Inside the skull, intricate formations of bone called nasal turbinates, rich in blood vessels, help warm the air the animals breathe. The hooves, broad and sharp edged, with big heel pads, make traction possible on steep rocky slopes and on ice.

The muskoxen of East Greenland are a bit smaller than those of Canada, so beautifully described by Barry Lopez in Arctic Dreams. They average about 48 inches at the shoulder with males weighing approximately 250 kilograms (over 550 pounds) and females 200 kilograms. Needless to say in this cold desert environment, the muskox's digestive system is very efficient, even more so than that of other ruminants. A unique species of bacteria in the rumen synthesizes extra nitrogen, making it available for digestion. Willow is the chief food, especially in winter. In summer there are a number of species of willow available as well as sedges, grasses and forbs.

Originally muskoxen lived only in the North and East of Greenland, as far south as Scoresby Sund. The immense Greenland glacier in the interior prevented their migration to the lush pastureland on the west coast. In 1963-5 twenty-seven individuals were brought to West Greenland where their descendants have thrived. Another seventy-five muskoxen were introduced into the western herds in the late 1980s and early 1990s, and there are now perhaps six thousand muskoxen in the west, while the total population of muskoxen in their native habitat in the North and East is between nine and twelve thousand individuals. This is positively not a threatened species! In the West the animals are heavier and reproduce earlier; whereas the population is merely stable in the North and East. It is growing by thirty-three percent annually in the West. Per one hundred cows in the West, one hundred nine calves are raised annually with calf mortality at less than ten percent. In contrast, in the North and East, where the population is stable, one hundred cows average a production of 47 calves with a mortality of fifty-five per cent.

The animals were introduced to the West to provide subsistence hunting for the native people, and the hunting quota there is now three thousand muskoxen a year. With such heavy hunting pressure being put on the herds of West Greenland, it is unlikely that the population will exceed the resource, which is always a danger with introduced species. However, muskoxen everywhere could be faced with the possibility of extinction due to global warming. Muskoxen, especially the calves, cannot tolerate wet, and one effect of global warming will probably be an increase of snowfall, and worse, rainfall in the Arctic. Barry Lopez tells of an early winter rainstorm in the high Arctic in 1973 that covered feeding grounds with ice. Forty-eight per cent of the herds on East Melville Island starved to death, and though herds have subsequently recovered, repeated incidents of this type brought on by warming in the Arctic, would cause disaster. Warming may also cause unpalatable species like dwarf birch to out-compete willows and grasses, the preferred food of arctic herbivores. ("The Hottest Spots," Jennifer Bogo, Audubon, 12, 2003) Once again we are brought back to the same "take home lesson." We bear a lot of the responsibility for global warming, and that warming is being felt first and hardest in the planet's high latitudes, where species like the muskox and the polar bear, so beautiful and so successfully attuned to their special harsh environment, face extinction. Must we then conclude that survival of the species just means the survival of humans?

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