The moose is the largest member of the deer family, defined by its dark coat, long legs, and the iconic palmate antlers of the male. These animals are symbols of the northern wilderness throughout North America. In the United States, their presence is concentrated in distinct regional populations that occupy the northernmost forests and highest mountain ranges. Their distribution is governed entirely by the narrow environmental requirements necessary for survival.
Major Regional Populations in the United States
The largest concentration of moose is found in Alaska, hosting the Alaskan Moose (Alces alces gigas). This population is estimated to be between 175,000 and 200,000 animals, distributed across the state’s vast interior and south-central plateaus. Isolated groups also exist in the Pacific Northwest, including northeastern Washington State and northern Idaho.
The second major grouping is the Shiras Moose (Alces alces shirasi), the smallest North American subspecies. It occupies the high-elevation habitats of the Rocky Mountains, extending through Idaho, Montana, Wyoming, and Utah, and reaching its southernmost range in Colorado.
A third significant population, the Eastern Moose (Alces alces americana), inhabits the spruce-fir forests of the Northeast. Maine holds the highest density of moose in the lower 48 states, with substantial numbers also thriving in New Hampshire, Vermont, and the Adirondack region of New York.
Essential Habitat Requirements
Moose distribution is restricted by their need to avoid thermal stress. Because of their immense body size and thick coat, they suffer from heat stress when temperatures rise above 27°C (80°F). During warmer periods, moose seek refuge in dense forest stands or spend extended periods submerged in water bodies to cool down.
The animals are primarily browsers, requiring woody vegetation, including the twigs and bark of willows, aspens, and balsam firs during winter. In the summer, they seek aquatic vegetation found in lakes, ponds, and wetlands. This aquatic forage is important because it provides a high sodium content often lacking in terrestrial plants.
Their forested habitat must feature a mix of early-successional areas, like clear-cuts or fire-regenerated patches, which promote the growth of palatable young shrubs. Winter survival is linked to snow conditions; while moose are adapted to deep snow, depths exceeding 80 to 90 centimeters can severely limit their movement and foraging ability.
Population Status and Conservation
Moose populations are experiencing varied trends, with stable numbers in some northern areas contrasting with sharp declines along the southern edge of their range. Populations in parts of Minnesota and New Hampshire have declined significantly over the past two decades. This decline is directly tied to the effects of a warming climate.
Milder winters are contributing to infestations of the winter tick (Dermacentor albipictus), a parasite that survives longer in warmer conditions. The ticks lead to severe anemia, extensive hair loss, and high mortality rates, particularly among calves.
Another significant threat is brain worm (Parelaphostrongylus tenuis), a parasite carried by white-tailed deer that is lethal to moose. As warming temperatures allow deer to expand their range northward, moose are increasingly exposed to the parasite, which causes neurological damage and eventual death. State wildlife agencies are responding with increased research, habitat management efforts, and adjusted hunting quotas.