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Moose

September 9, 2024

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Alces alces americana

An icon of the Maine woods, Maine is home to the highest moose population in the lower 48 states. The scientific name for moose is Alces alces americana – origin of the word moose comes from the Algonquin word ‘moosu’ meaning ‘bark stripper.’

Habitat

Bulls (males) and cows (females) use somewhat different habitats during the summer, which is a tradeoff between cooler temperatures for bulls and raising calves for cows. Bulls are typically found at higher elevations in mixed and hardwood stands, where food supply is less available, but shading provides cooler temperatures. Cows are found at lower elevations in regenerating stands and adjacent softwoods, because food is more concentrated. This concentrated food source limits the amount of time cows spend feeding, which limits calf’s vulnerability to predators. Moose winter where more hardwood browse is available, and they often feed in regenerating stands. Mature softwood is used as cover when snow depth exceeds 3 feet.

Diet

Moose are herbivores, meaning they only eat plants. They survive on browse, the leaves and twigs of woody plants. Willow, aspen, birch, maple, pin cherry, and mountain ash are important, high quality browse utilized by moose throughout the year. In addition, and since leaves are absent from hardwoods in the winter, balsam fir provides additional value for moose over the long winter. However, moose cannot survive on balsam fir alone, because it has lower nutritional value. By selectively browsing certain species of plants, moose help shape young forest stands and keeps many plant populations under control.

Sodium is also important to moose. Aquatic plants, such as pondweed and water lily, have higher sodium content than woody vegetation and are an important part of a moose’s diet. Natural salt licks are rare in Maine, so moose are often seen along roads using the salt runoff as an artificial salt lick.

Distinctive Characteristics

The largest member of the deer family, moose stand up to seven feet tall, sporting dark brown fur and a shoulder hump. Female moose (3.5+ years old) average 836 pounds and the average prime age (5.5+) adult bull weighs 1,106 pounds. The largest bull ever harvested in Maine had a dressed weight of 1,330 pounds and means it would have weighed approximately 1,767 pounds! The total length of a moose is about 9 feet and the front hoof width is about 5 inches for a prime bull, just under 4 inches for a cow, and just under 3 inches for a calf. A cow has a brown face and dark body and a bull has a black face. Both cows and bulls have “bells”, skin flaps found on the neck. A cow’s bell looks more like a tuft of hair, whereas a bull’s bell is larger and rounder. Some bulls may have an additional tuft of skin extending below the bell, but it is believed that this extension freezes off.

Nocturnal/Diurnal

Active mostly at dusk and dawn.

Seasonal Changes

Males have large, palmated antlers during the mating season that they shed and regrow each year. The antlers help show their dominance and protect their eyes when competing for a mate. They will also splash their antlers with urine, a scent that entices cows to breed.

Once the mating season is over, bulls no longer need antlers so they shed them early winter. This helps them conserve energy during the cold winter months. In the spring antler bone begins to grow inside a skin covering the moose’s antler, called velvet. Antlers are one of the fastest growing tissues of any animal. Antler can grow as much as 8 inches in just nine days. As testosterone surges in a bull in September the velvet begins to shed, leaving behind bare antlers.

Antlers on cows are extremely rare. Calves may have small buds by late September, yearlings may have spikes or small forks, and palms typically first develop in two and three-year-old bulls. Maximum antler development is obtained at age five and declines when bulls are in their teens. A bull’s antler spread rarely exceeds 65 inches and a spread of 55 inches is considered large.

Reproduction & Family Structure

The breeding season (rut) for moose begins in late September and lasts into early October. Cows may produce their first calf when they are two, and most produce a calf by age three. Each May, cows give birth to one to two calves. Cows rarely have more than two calves and young cows rarely have twins. A cow’s nutritional condition, or body weight, determines the number of calves born and when a cow first breeds. Moose continue to breed into their teens but may be less productive. Calves remain with their mother for one year and are driven off shortly before the next calf is born. Bulls are able to breed as yearlings, but most do not breed until they are older and can compete with other larger bulls.

Survival & Threats

Survival: The average life expectancy is eight years for a cow and seven years for a bull. Moose may live into their late teens, but rarely live past 20. Natural predation for moose in Maine is low, because predators aren’t capable of killing adults, however, young newborn calves can be vulnerable to predators such as coyote and bear. Moose can also perish from legal and illegal harvest, road kills, other accidents (drowning, falls, etc.), disease, starvation, and old age. Harvest and road kills account for 2,000 to 3,500 moose a year.

Threats: In recent years, moose have been impacted by new threats due to a changing environment and climate. As climates continue to warm, parasites and diseases are able to expand in range and have a greater impact on the moose population. White-tailed deer are hosts to brain worm but are not impacted by it – however, it easily spreads to moose and causes neurological deficits and often death. Winter ticks are also threatening Maine’s moose population. Unlike deer ticks, winter ticks do not spread disease. The problem is that they attach by the thousands and stay attached for five or six months, causing moose to experience life-threatening blood loss, hair loss, and even behavioral change. Learn more about winter tick.

Management & Conservation

Distribution & Population Trends – According to writings of early explorers, moose were plentiful in New England during the 1600s. By the early 1900’s, moose populations in Maine had declined to an estimated 2,000. This decline was mostly attributed to unrestricted hunting. Clearing forestland for farming and increased incidence of brain worm which attributed to increasing deer populations also contributed to their decline. During the 1900’s, laws protecting moose from excessive hunting and improving habitat conditions allowed the moose population to increase. Moose likely reached their highest population by the year 2000 and pioneering new techniques MDIFW estimated moose at around 76,000 in 2012. Since the recovery, climate change has begun to influence the success and proliferation of winter tick, leading to poor reproduction and low calf survival through the first winter. Without intervention, biologists believe that the population will likely destabilize, but MDIFW’s biologists are working to implement adaptive methods to keep our moose population healthy and stable for the future. Learn more about the Adaptive Management Study.

Historical Management – During the 1975 and 1980 planning process, a harvest goal was established, but population size and non-consumptive use goals were not established. An objective of 1,100 to 2,200 moose harvested annually was made to meet the harvest goal. During the 1985 planning process, goals to maintain moose numbers at 1985 levels (21,150), increase harvest, and maintain viewing opportunity were established. Population, consumptive, and non-consumptive objectives were developed to meet these goals.

In 2000, a big game working group developed goals and objectives to guide moose management in Maine until reassessment in 2015. These were more comprehensive than the goals developed in 1985 that essentially directed us to maintain the population at 1985 levels. The 2000 population goals and objectives are specific to each Wildlife Management District (WMD) but are grouped in three Management Areas:

Recreation Management: Maintain the population at 60% of carrying capacity to maximize hunting and, for most of the WMDs, viewing opportunity.
Road Safety: Reduce the population significantly to reduce moose/vehicle accidents.
Compromise: Reduce the population by 1/3 to reduce moose/vehicle accidents and maintain some quality recreational opportunities.

The current moose management goals and objectives for 2017-2027 are:

Goal #1: Maintain a healthy moose population while providing hunting and viewing opportunities.

Stabilize the moose population in the core of its range (WMDs 1-11 & 19)
Manage WMDs 1 & 4 for bull:cow ratios of 30-50 bulls:100 cows in order to increase opportunities for harvest while ensuring healthy reproductive rates
Manage all other WMDs in core moose range (2,3,5-11 & 19) for an older bull age structure and bull:cow ratio of 50-70 bulls:100 cows in order to provide opportunities to harvest and view mature bulls while ensuring at least 17% of the population consists of bulls older than 4 years old
Refine the moose management system to allow adjustments to moose population size based on measures of moose health or density

Goal #2: Continue researching the relationships between moose, parasites, habitat condition, climate, and management

Develop an improved understanding of moose mortality and population dynamics
Develop an improved understanding of the effects of parasite loads on moose reproduction and calf survival, and how parasite loads may vary with moose densities and habitat conditions
Develop an improved understanding of winter tick ecology, especially the relationship between winter tick population dynamics and environmental variables
Develop an improved understanding of the impacts of moose browse on forest regeneration

Goal #3: Ensure public satisfaction with Maine’s moose population and increase the public’s understanding of moose biology, ecology and management

Minimize agricultural conflicts with moose and the number and severity of moose-vehicle collisions
Increase viewing opportunities for moose
Maintain a world class moose hunt in Maine’s core moose range
Clarify and improve moose hunting regulations to ensure a legal and ethical moose hunt
Maintain or increase current levels of satisfaction by moose hunters in core moose range