Moose. Alces alces DISTRIBUTION

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1 Moose Alces alces In the boreal forests of the Northern Hemisphere, the Moose is one of the most important links in the food chain. The largest member of the deer family, this massive vegetarian is a source of food for a range of large predators including the wolf, Grizzly Bear, Black Bear and human. Smaller predators and scavengers such as the Wolverine, Coyote, Red Fox, lynx and even the raven depend on the remains of Moose killed by wolves and bears. Moose range from the Arctic coasts of North America, Europe and Asia down to the southern limits of the worldwide boreal forest. In North America they reach their southern extent in New York State to the east and Utah to the west. But today, few areas in the world support large, naturally regulated populations of Moose and their predators, and even in Yukon the situation is changing. DISTRIBUTION Moose inhabit the entire Yukon but are most numerous in the southern parts of the territory. In recent years biologists have conducted airborne population counts over about 15 percent of Yukon landscape. Based on these continuing studies it is estimated that approximately 70,000 Moose live within the boundaries of Yukon. Moose are not evenly distributed over the land, but tend to be clumped together in certain habitats. The few Moose that inhabit the Yukon's North Slope are concentrated in narrow strips of forest along the rivers that run down to the Arctic coast. In southern Yukon, about two thirds of all Moose are found at tree line in the subalpine shrub zone, which represents only 15 percent of the land area. In locations with low snowfall, Moose will remain in this shrub zone most of the year. Other Moose concentrate in recent burn areas, and along waterways with interconnecting marshes, ponds and meandering streams. CHARACTERISTICS Two subspecies of Moose are recognized in Yukon and their origins date back to the Wisconsin glaciation. For thousands of years an ice free portion of northern Yukon and Alaska known as Beringia was separated from the rest of North America by huge continental ice sheets. About 12,000 years ago, Moose that had been isolated in Beringia slowly moved southward to occupy the new landscape when the ice melted away. At the same time, Moose from the lower continent expanded their range northward, eventually reaching the southern Yukon. When the two species met they began to interbreed, and today Yukon is considered a transition zone between the Alaska Yukon, or Tundra, Moose (Alces alces gigas), and the Woodland, or Northwestern, Moose (Alces alces andersoni). With adult males approaching 700 kilograms, the Alaska Yukon Moose is the largest subspecies in the world. Bull Moose antlers, which are grown and cast off each year, are a dramatic characteristic of this species. Two types of antlers are found in yearling bulls. The cervicorn type varies from a single spike to a small fork, with or without additional points. The palmicorn type has small palms with several points or protruberances. At two years of age nearly all bulls in Yukon have small, but well developed palms on

2 their antlers. The size of the palms, antler spread, and number of tines, increase each year until the bulls reach their prime at about six years of age. After the prime years, antlers may become slightly smaller and begin to deform. Although the Moose has relatively poor eyesight it has a keen sense of smell and mule like ears which can capture the faint sounds of a stealthily approaching predator. Its large overhanging snout is equipped with self sealing nostrils which allow the animal to submerge its head when feeding on aquatic plants. A flap of skin hangs from its throat, but serves no known purpose. The long legs and splayed hooves of the Moose can carry it through a variety of rough terrain; over windfall in thick forests and bum areas, through the deep snow of winter, across rivers and ponds, and through boggy swamps and marshes. A YEAR IN THE LIFE Spring As the snow cover begins to melt and flow downslope to the frozen stream beds, pregnant cow Moose look for safe and secluded places to give birth. Calves are born from mid May to mid June. Some cows birth at tree line in the subalpine zone, while others birth at river level in the valley bottoms. In the southwest Yukon, Grizzly Bears which spend much of their time in the subalpine in spring kill about 50 percent of each year s calf crop. Most of these kills are made before the calves reach eight weeks of age. Wolves take fewer newborn calves than grizzlies, but continue to prey on the older calves year round. Most cows breed for the first time at 18 months of age and every year afterwards. When cows are in good nutritional condition, they can give birth to twins.. From late spring through the summer, Moose feed on the new buds and fresh growths of willow. Aquatic plants like the yellow pond lily draw the long legged Moose out into ponds and lakes at this time of year. Antler development begins in April or May, first in older bulls and last in yearlings. During the growth period, the soft spongy antlers are covered with a dark brown, velvety skin. Summer Waterways are important feeding areas for Moose, but they also provide escape routes from the everpresent danger of predator attack. When pursued by wolves or bears in the summer season, Moose head for water where their long legs give them an advantage. The Moose is a browser; "eater of twigs" as the Algonkian First Nation name translates. In a single day, an adult can consume about 20 kilograms of twigs, leaves, shrubs and other land and water plants. A ruminant like the domestic cow, it has a series of stomachs to help digest its woody diet and can sometimes be seen chewing its cud.

3 Those calves that survive through the heavy spring predation grow dramatically over their first summer. Adding as much as two kilograms per day, they weigh about 180 kilograms (400 pounds) by the time autumn arrives. Fall Cow Moose can experience several breeding periods in the fall. The first oestrous, which occurs between the last week of September and the first week of October, is the period of greatest fertility. Rutting, brings new sounds to the landscape. The coughs, grunts, and bellows of bull Moose are heard along with rubbing of antlers against trees and the calls of the cows. Finally the clash of antler to antler resounds as two bulls collide and begin their shoving match. Dominant bulls try to keep lesser bulls away from their group of cows, which can number up to ten or more. At the same time, the bulls continually monitor their cows, ready to mate with any that come into oestrous. All in all it's an incredibly demanding time for these bulls. They stop eating for a month or so during the rut; their necks swell and they become unusually aggressive. But it's short lived power they wield. When the rut is over in October, many of the dominant bulls are exhausted, under nourished, and have lost up to 20 percent of their weight. Sometimes the price for perpetuating his genes is a weakened state that leaves the bull more vulnerable to potential causes of mortality. Most bulls drop their antlers from late November through December, while young bulls lag a month or more behind. Winter Winter is a season of reduced food supplies for Moose. Fresh willow buds, leaves and aquatic plants are no longer available. Forage is restricted to the woody twigs of poplar, birch, alder and willow. In late winter when food supplies are at their lowest, some Moose move into aspen stands and use their front teeth to scrape the bark down to the nutritious layer of cambium underneath. In parts of Kluane National Park and other areas of heavy snowfall, many Moose will move down to the lower valleys as winter progresses. Although the wolves tend to concentrate on calves and older age Moose, any Moose can be vulnerable to wolf predation, depending on the terrain, snow conditions, and its response to attack. Generally, a Moose that remains stationary can successfully defend itself from wolves, while a Moose that flees is attacked from the rear and often brought down. By backing into a thicket of trees, a Moose can fend off wolves with its powerful front hooves. MOOSE AND PEOPLE

4 Moose meat has helped to support the lives of Yukon First Nations people for thousands of years. There have been periods, however, when Moose were virtually absent from Yukon. Apparently, during the early 1900's few Moose were present in the territory and the First Nation people of the time relied mainly on caribou for food. When Moose were present, like caribou, they were guided into snares or killing corrals by long brush fences. The snares were made from strips of half tanned hide. A dozen or so strips would be braided together to make a strong cable about one or two centimetres in diameter. When set in an opening in the brush fence and tethered to a heavy drag pole, the snare would catch a Moose around the neck and hold it until it became exhausted. Moose were also killed with bows and arrows, but the hunter often had to trail the animal for days before it dropped; not an easy task. Today, Moose hunting provides many Yukoners with recreation as well as lean, chemical free meat. For First Nations people, it also helps to maintain their link to the land and their culture. Much of the Moose hunting effort is concentrated along roadways, and in some areas this has led to declining moose populations. DID YOU KNOW? In the rutting season, bull Moose create wallows (shallow depressions in the earth) about one metre in diameter. They urinate in the wallows, and then roll in them, giving themselves a high odour that cows in breeding condition can detect at great distances. To get at the fresh leaves near the top of young aspen trees, Moose will sometimes straddle the sapling and walk forward, pushing with their chests until the sapling leans down within reach. When threatened, Moose strike out with their front hooves. Bulls may also charge with lowered antlers. Until recently, Yukon First Nations used Moose hide boats for river and lake travel. The remains of such boats can still be seen on the banks of some Yukon rivers. VIEWING OPPORTUNITIES Many Yukoners can remember when Moose were commonly seen along roadways. Today, road travellers are occasionally fortunate enough to see a Moose crossing the roadway or feeding on the edges of nearby ponds or meadows. But the determined viewer or photographer is best advised to leave his or her vehicle behind and paddle, hike, or travel by horseback or river boat into the wilderness. Travellers on the less popular Yukon rivers are almost certain to see Moose, especially in spring and early summer. In the fall, when rutting groups are at tree line, a hike up the mountainside can be very rewarding. Caution is advised as bull Moose in the rut can be dangerous. Bring your binoculars, and remember that Moose are most active at dawn and dusk.

5 IDENTIFICATION A bull Moose with antlers is difficult to confuse with any other animal. It is much larger and darker than a caribou, Mule Deer or Elk. Its antlers have broad palms while those of the other deer have generally narrow beams. A cow Moose is also larger than a caribou, Mule Deer or Elk. It is darker in colour than the other deer and its legs are longer. To distinguish between a bull Moose and a cow during the antlerless period, look for antler scars on the bull's forehead (dark round buttons), and a white vulva patch under the cow's tail.