Moose, Caribou (Reindeer) and Sitka Black-tailed Deer
Three deer species live at the zoo: Moose, Caribou (reindeer) and Sitka Black-tailed Deer. Back to animal directory.
Moose
Alces alces gigas
LIFE SPAN: 20 years under human managed care.
RANGE: Moose are the largest member of deer family, with the Alaskan subspecies largest of all. In Alaska, moose are found from the panhandle to the Arctic coast. Moose like recently burned areas that contain fresh willow and birch. They are found along ridges and major rivers throughout the Southcentral and Interior regions of Alaska.
SIZE: Moose range in size from a small adult female at 800 pounds to a large male at 1,600 pounds.
PHYSICAL FEATURES: Only males grow antlers which can be 81 inches wide and weigh 71 pounds. Antlers are covered in velvet while they grow, followed by the velvet being scraped off and shed after growth stops for the season. This signals the start of the rut, or breeding season. Antler growth peaks at 10-12 years and size declines by age 13-14.
FOOD: Fall and winter food consists of birch, willow, and aspen twigs. In the spring, they feed on sedges, horsetail fern, aquatic plants and grasses. In the summer, they eat birch, willow and aspen leaves (along with aquatic plants).
BEHAVIOR: Moose are good swimmers able to dive down to 20 feet. They appear slow, but run up to 35 miles per hour. They may get stuck in deep snow, making them easy prey for wolves in these situations. They often take trails or roads to travel avoid deep snow in winter.
CONSERVATION: Populations are stable overall. There are differing opinions on how they should be managed in areas where slow declines are seen. Some prefer predator control to boost calf success, while others believe that populations go through a cyclic rise and fall.
PLANT NOTES: Moose browse on willow, birch, fireweed, alder, moss, lichen and aquatic vegetation. Their browsing has a significant impact on plant growth, both positive or negative. Their feeding stimulates new plant growth, although over-browsing can reduce new growth in some cases. The density and presence of certain plants in winter months can be a limiting factor for moose.
Caribou (reindeer)
We have caribou and reindeer. Reindeer are the domesticated version of caribou. Much of their biology is the same but there are differences in body composition because reindeer are traditionally bred for meat.
Rangifer tarandus
LIFE SPAN: 20 years under human managed care.
RANGE: Caribou are found in the tundra and northern forests of Alaska and Canada. There are 32 distinct herds in Alaska. The largest is the Western Arctic herd, followed by the Porcupine herd.
SIZE: Caribou bulls weigh up to 400 pounds, females smaller.
PHYSICAL FEATURES: Male and female caribou (reindeer) grow antlers. Bulls lose their antlers after fall rut, while pregnant females keep theirs until shortly after birth. Caribou have no undercoat, just hollow hair with thick tips that overlap to trap warmth. Ankle tendons move across the bone to allow hooves to spread for walking on soft tundra. Hoof edges harden in winter to act as cleats.
FOOD: Herds can be over 10,000 caribou, so they migrate to find food. They can migrate up to 3,000 miles per year, more than any other land mammal. They prefer willow, birch, grass and sedges in summer. They eat lichens and dried grasses in fall and winter, often sniffing them out under the snow.
BEHAVIOR: Caribou give birth from April to June. In a herd, calves are born born within one week causing confusion for predators who have trouble pulling a calf from the crowd. Calves walk within an hour and outrun a human by one day old, then travel with the herd. Caribou sprint 50 miles per hour.
CONSERVATION: Herds are studied to determine impacts of oil development. Populations are stable, although some herds experience declines. The Peary subspecies on islands in the Northwest Territories, Canada is endangered.
PLANT NOTES: Areas of “calcium-rich” tundra, often on the coastal plains, are important for caribou. This tundra has less moss and shrubs, with higher plant diversity. As global temperatures rise, tundra is turning more acidic (wet). This has less nutritional value for wildlife.
Sitka Black-tailed Deer
Odocoileus hemionus sitkensis
LIFE SPAN: 10 years average, although they live up to 20 years under human managed care.
RANGE: Sitka deer are native to the wet, coastal rainforests of southeast Alaska and north-coastal British Columbia.
SIZE: Their average weight in the fall is about 80 pounds for does (females) and 120 pounds for bucks (males).
PHYSICAL FEATURES: Their summer coat is reddish-brown, with a winter coat of darker brownish-gray. The Sitka deer is the smallest deer species in Alaska.
FOOD: They eat grasses, sedges, cabbage, leaves of berry bushes and other woody plants.
BEHAVIOR: Breeding peaks in late November for this species. Does (females) begin breeding during their second year of life and continue producing fawns each year until they are 10-12 years old. Sitka deer move down from the high mountain peaks and spend their winters on lowlands and beaches where snow is more shallow. In deep snow, they may suffer losses and starvation as they are unable to find food. During heavy snow times, deer will pack down trails and other deer in the area will follow these trails to move and forage. In the summer, they travel back up to the higher altitudes in the mountains.
CONSERVATION: Populations are stable in Alaska, however they are prone to wide fluctuations due to severe weather and deep snow. A bigger issue for this deer species is the loss of old-growth forest, logged and replaced by successive forest growth which results in a closed and uniform canopy. This converts once productive forests to very poor quality deer habitat. Declines are expected in the future as logging cycles complete. In some areas, illegal hunting and under-reporting harvest has had an impact and sometimes represents twice the legal harvest.
PLANT NOTES: During summer months, these deer feed on a wide variety of leafy plants including include willow, fireweed and bunchberry. Winters of deep snow mean less variety for foraging and a switch to woody plants found in the spruce and hemlock forests. Preserving these forests is critical to winter survival.