Moose

Moose

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Description

Moose are the largest species in the deer family with long, slender legs that support a massive body and a short, thick neck and humped shoulders that support a large head.  The Alaska-Yukon race is the largest of all moose.  Only bulls have antlers and they are the largest of all animal antlers, over six feet wide and 80 pounds.  Antler is the fastest growing tissue of any mammal, growing a pound and an inch a day in summer.  They start growing in spring and are shed each winter annually.  Anters are palmate, having main and brown palms in a butterfly shape.  Fur is generally dark, black to brown or grayish brown, with the lower legs being lighter and their underfur and long guard hairs provide excellent insulation from the cold. 

Lifestyle

Moose are the least social species among the deer family, remaining fairly solitary except during the mating season.  They are not territorial.  Outside of the rutting period, males and females are separated spatially, seasonally, and/or by habitat. Moose are crepuscular by nature, being most active at sunrise and sunset.  Despite their ungainly appearance, moose are able to run silently through dense forests.  Maximum speeds have been clocked at 35 mph.  Moose are also strong swimmers, being known to swim up to 12 miles.  Their daily pattern includes traveling to new feeding sites, avoiding predators, browsing on plants, standing, and lying down for the rumination of their food.  Moose mainly stay in the same general area, though some populations seasonally migrate up to 110 miles. Home range size of moose varies between 1.4 to 35 square miles.  During their first year of life, young moose occupy the same home range as their mother and do not establish their own home range until the age of two.

Food Habits

Moose are herbivores and primarily browse upon the stems and twigs of woody plants in the winter and the leaves and shoots of deciduous plants in the summer.  Willows are the most preferred forage where available.  In interior Alaska, willows accounted for 94% of the biomass consumed in the winter.  Food quality depends on twig bite size, fiber, species, and spacing in habitat.  During winters of deep snow, food may be inaccessible to moose.  They have a difficult time walking in snow depths of greater than 3 feet.  During summer months, moose often feed on aquatic plants in ponds and lakes.  They can dive to 20 feet in search of plants.  This food is highly digestable and abundant in many areas.  An adult requires about 44 pounds of food per day to maintain energy levels for foraging and traveling.

Lifecycle

Moose breed in September and October of each year, during a breeding season often referred to as "the rut".  Gestation averages about 231 days, with cows giving birth to one calf on average and often twins.  Calves are born at an average weight of 36 pounds and gain approximately 2.2 pounds per day while they are nursing.  Males and females are sexually mature at two years of age, but full growth potential isn't reached until four or five years of age.  At that age, females are at their reproductive peak and males have the largest antlers.  Moose are polygamous, and only females take care of their young for a period of one year.  Females seek secluded sites to give birth to young and remain highly protective until their calves are weaned.  Calves can browse and follow their mother at three weeks old and are weaned at five months.  They remain with their mother until about one year after their birth, when the mother's next young is born.

Population Status, Threats & Conservation

Moose are important to Alaskans, especially as a food resource. Sightings are enjoyed by Alaskans and visitors alike. Moose need good summer habitat to gain fat for winter, when they lose up to 25% of their weight. Wetlands are important in summer, protecting calves from bears and helping cows gain weight. Winter is a constant struggle to avoid deep snow while finding food, all while escaping predators like wolves. Biologists look at how many cows have twins as a good sign of moose health and habitat quality.  Populations are stable overall in Alaska, with some lower than others depending on regions of the state.  Close attention is paid to managing moose for population health first, then hunting and subsistance use.

Elements of nature impact moose habitat. Fire is good, creating plants that feed generations of moose. Deep snow is difficult, with snow deeper than three feet forcing moose find other habitat. Ice makes twigs hard to eat and allows easier travel for predators like wolves.

Sources:
Moose species profile, ADFG
De Bord, D. and L. Olson. 2009. "Alces alces" (On-line), Animal Diversity Web