Moose in New Hampshire

Moose abundance is monitored using the sighting rate by deer hunters, the deer hunter survey. Deer hunters are asked to record the amount of time they hunt and the number of moose they see. This provides a sighting rate of moose, which was compared with the actual number of moose [moose density measured with aerial thermal surveys]. Aerial surveys have been too expensive and logistically challenging to conduct on a periodic basis, therefore hunter sighting rate of moose is used to estimate moose density and periodically assessed for accuracy with aerial surveys. Additional information on the age and physical condition of moose is derived from samples collected at mandatory check stations during the hunt.

Fish and Game is partnering with the University of New Hampshire to evaluate our current methods for monitoring the moose population and investigate new methods.
 

Moose in New Hampshire are limited by:

• Quality habitat. Moose do best in large blocks of forest that have a mixture of conifer cover and young forest. Sustainable forest management and logging creates this type of forest. Conservation of land and development planning reduce habitat loss.
• Winter tick parasitism. Moose in northern New Hampshire are limited by winter tick parasitism. This is due to moderate to high local moose densities as well as the current trend of shorter winters caused by climate change. High density moose populations could be reduced with hunting to improve moose health. 
• Brainworm parasitism. Moose throughout New Hampshire in areas with moderate to high deer density are likely limited by brainworm parasitism. Deer density can be moderated with hunting.

Management goals are developed every 10 years in the Game Management Plan and the current plan is in effect from 2016 to 2025. The goals and actions taken to achieve goals are below.

Goal 1: At the management region scale, manage for an abundance of moose that balances and incorporates social, economic, public safety and ecologic factors, using the best available science. 

Action: Fish and Game partnered with University of New Hampshire (UNH) researchers in 2024-2018 to learn about what is influencing the moose population in northern NH (core population). Winter tick parasitism was found to be limiting the population and winter ticks are abundant because of moderate to high local moose density and climate. Follow-up research, also with UNH, on how to best measure moose density is ongoing. Hunting has been conservative (harvest 1-2% of the population per year) during this time when we are learning about management approaches. Also, due to social concern about hunting moose populations lower than 20 years ago, cut-off levels were put in place for hunting permit issuance. 

Goal 2: Maintain a desirable adult sex ratio and adult and yearling cow weights and minimize winter tick impacts. A desirable adult sex ratio is one where there are enough males for timely breeding of females. Winter ticks make moose unhealthy and weight reflects moose health, with heavier moose being healthier.

Action: Hunting harvest uses either sex permits to minimize the potential for the population sex ratio to become skewed due to hunting. Research with UNH on factors influencing the moose population was conducted to learn about the cause for poor moose health. Winter tick parasitism was found to be limiting the population and winter ticks are abundant because of moderate to high local moose density and climate. Follow-up research, also with UNH, on how to best measure moose density is ongoing.

Goal 3: Residents and visitors will understand, appreciate and value the role of and possibilities for moose in our changing ecosystem. 
Action: The Fish and Game website and public presentations, upon request, provide information on the status of moose in New Hampshire.
Goal 4: Fish and Game will work alone and in partnership with state, federal, and public and private partners to minimize the loss of important moose habitat and to conserve, protect and enhance moose habitat through education and the expenditure of technical and financial resources. 

Action: Education efforts are ongoing and moose are benefiting from sustainable forest harvesting on federal, private, and state property. There is much potential to manage for moose and wildlife in general, so please reach out if you are interested in learning more. Call (603) 271-2461 or email wildlife@wildlife.nh.gov.  
 

The primary way climate change is affecting moose is through increased winter tick and brainworm parasitism. Winter ticks have higher survival in climates with short winters. Brainworm is spread by deer and less severe winters improve deer survival.

Moose minimize the influence of high temperatures by selecting cool areas and altering their activity pattern to coincide with the coolest times of day. This strategy is most effective when moose have quality habitat (mature conifer forest interspersed with young forest and wetlands).
 

Moose can have thousands of winter ticks on them. Moose with more than 30,000 winter ticks are substantially affected by the large of volume of blood they lose to feeding winter ticks in March to May. At this time of year, moose are naturally in their poorest condition. The added burden of blood loss to winter ticks causes young moose (10-12 months old) to die and adult female moose to be in poor condition and have fewer resources for producing calves the upcoming spring.

Learn More About Winter Ticks  

Adult brainworm living in the brain of deer produce larvae which are passed in the feces of the deer. Slugs and snails that crawl on the deer feces become infected. Deer and moose then become infected when they accidentally ingest slugs and snails with the worm while browsing.

Infected moose display a variety of symptoms that all relate to impaired control of body movement.

Common symptoms include:

• Loss of coordination, particularly rear legs. Stumbling and unsteady stance.
• Head tilt.
• Repeatedly walking in tight circles.
• Inability to stand.

It is unknown if moose can survive brainworm infection. Researchers found that young moose infected with a low dose of brainworm developed mild incoordination that dissipated over time. Moose infected with moderate and heavy doses developed non-resolving incoordination. All of these research moose were euthanized at the end of the one year trial, so the long term influence of infection is unknown. Also, these moose were infected using an injection of brainworm larvae and not fed infected slugs and snails as the case for wild moose.

Learn More About Brainworm  

Moose in New Hampshire can be broadly considered as three populations, those in northern NH, White Mountains, and southern NH. In all of these regions the abundance of quality habitat (mature conifer forest with interspersed patches of young forest and wetlands) has the largest influence on the moose population.

Northern NH (North and Ct. Lakes management regions):
This area has high quality moose habitat and moose occur at moderate to high local density. The population is generally stable but moose are in poor condition due to winter tick parasitism. 

White Mountains (White Mountains management region):
This area has moderate quality moose habitat and moose occur at low to moderate density. The population is generally stable and likely in moderate condition. Moose are primarily limited by the amount and distribution of young forest, as well as brainworm parasitism in areas with high deer density and winter ticks in areas with moderate to high moose density.

Southern NH (Central, Southwest, and Southeast management regions):
This area has low to moderate quality moose habitat and moose occur at low density. The population is stable or slightly declining. Moose are primarily limited by habitat quality, and likely brainworm parasitism in areas with high deer density. We believe that this population was previously bolstered by emigration from populations in northern New England.
 

Currently, there is not a realistic method to kill winter ticks. The recommended approach for reducing winter tick impact is to keep local moose density low to moderate to prevent build-up of the winter tick population. Methods to manage moose density include regulated hunting and forest management in the long-term.

Many people wonder if winter ticks can be controlled in ways similar to how people control ticks on domestic animals. These approaches include treating animals or the landscape with acaracide (pesticide for ticks). Treating enough area or moose every year presents logistical challenges that currently preclude treatment. The effect of acaracides on the ecosystem would need to be carefully considered prior to use. Winter ticks are a natural part of New Hampshire’s ecosystem.

There is a fungus that kills winter ticks and naturally occurs in the soil. A method for using this fungus to control winter ticks has not yet been found.
 

Moose are more likely to become infected with brainworm when they use the same habitat as deer. The more deer there are in an area, the greater the chance deer and moose will use the same habitat. Keeping deer density moderate or low with regulated hunting would minimize the chance for moose infection with brainworm.

Moose hunting will be suspended when the population is too small to support harvest or residents do not support regulated moose hunting, whichever comes first. Biological data is monitored to ensure hunting is not impacting the viability of the moose population. Public support for moose hunting is evaluated with surveys every 10 years.

No. The current level of hunting harvest (1-2% of the population) does not influence the long-term trajectory of the moose population. New Hampshire’s moose population is currently fluctuating based on the quality of habitat and impacts from winter tick and brainworm parasitism.