Moose Toxicology

AITRC works to conserve, manage, and develop fish, wildlife, and plant resources in the Ahtna Territory according to culturally relevant values. AITRC incorporates scientific best practices with traditional ecological knowledge to fill data gaps to better inform management and answer questions or concerns brought to us.

AITRC's Board and other tribal citizens brought concerns over changes in the subsistence foods they consume. After hearing these concerns, AITRC formed the Moose Health Monitoring Program. Moose have a cultural and economic importance, as well as, a practical importance to subsistence harvesters. Living off the land means cleaner, fresher, and more nutritious food. Monitoring the health of harvested moose will allow us to identify areas of concern, whether that be moose reproduction, moose health, or human health.

Funded by the Windward Fund and the U.S. Environmental Protection Agency (EPA) through the Indian Environmental General Assistance Program (IGAP), in partnership with Texas A&M University, the University of Alaska Fairbanks, and Dartmouth College.

Moose Health Monitoring.

Moose are an important part of life throughout the Ahtna Territory. They provide food for families, support cultural and subsistence traditions, and are an important part of the ecosystem. Because of their importance to both people and the land, understanding the health of local moose populations is a priority.

This project studies essential and non-essential elements in moose harvested across the Ahtna Territory. Some elements, such as zinc and copper, are nutrients that animals need in small amounts to remain healthy. Other elements can become harmful when they accumulate at elevated levels.

By examining these elements in different moose tissues, researchers are working to better understand the nutritional health of moose, potential exposure to contaminants, and what those patterns may mean for both wildlife populations and people who rely on moose as a subsistence food.

Community-Based Sampling.

Local hunters played an essential role in building the dataset for this project. AITRC distributed sampling kits that allowed hunters to collect biological samples during their normal subsistence harvests.

Participation grew substantially during the project:

2022 — 8 sample kits returned
2023 — 33 sample kits returned
2024 — 41 sample kits returned
2025 — 36 sample kits returned

These samples provide a valuable baseline for understanding moose health across Ahtna Territory and allow researchers to look for patterns that may not be visible when examining individual animals.

AITRC is no longer collecting samples for this project. Current work focuses on analyzing and interpreting the information collected during previous sampling seasons.

Sample Collection.

AITRC is asking harvesters to collect samples from moose. The size of the samples are:

Liver (2 in x 2 in)
Kidney (a 1/2 in slice from center)
Muscle Tissue (2 in x 2 in)
Jaw bone or 2 incisor (front bottom) teeth
A large chunk of hair
A blood sample collected with paper provided

Please keep samples frozen until they can be delivered to AITRC or an AITRC employee can pick them up.

What do you do with the samples?

Different biological samples provide different pieces of information about an animal's health, diet, environment, and life history. AITRC is currently analyzing the samples for essential and non-essential elements and various diseases.

Biological samples can also provide information about disease, nutritional condition, and other indicators of animal health.

Combining these results with information such as an animal's age, sex, harvest location, and physical condition provides a more complete picture than any single measurement alone. Over time, these data can help researchers distinguish normal variation among individual moose from broader patterns that could indicate changes within the population or environment.

This information will let us examine the health of the moose and the implications of consumption.

Essential and Non-Essential Elements.

Moose are exposed to naturally occurring and human-associated elements through the plants they eat, the water they drink, soil, and the surrounding environment. Tissue samples can be analyzed to determine the concentrations of different essential and nonessential elements within an animal.

Essential Elements.

Essential elements are needed in small amounts for normal biological functions. These include elements such as copper, iron, manganese, and zinc. However, even essential elements may become harmful when concentrations become too high.

Non-Essential Elements.

Non-essential elements have no known biological role and may be harmful even at relatively low concentrations. Examples include cadmium and lead.

Moose encounter these elements primarily through the plants they eat. Because soil conditions, geology, vegetation, and environmental changes vary across the landscape, the amount and type of elements a moose is exposed to can also vary.

Over time, some elements can accumulate within an animal's tissues, a process known as bioaccumulation. Studying those concentrations can provide information about environmental exposure, nutrition, and wildlife health. By examining these concentrations across multiple animals, researchers can begin establishing baseline conditions and identifying patterns that may warrant additional investigation.

What Is Bioaccumulation?

Bioaccumulation occurs when certain substances build up in an animal's body over time. Moose can be exposed to elements and other substances through the plants they eat, the water they drink, soil, and the surrounding environment. When a substance enters the body faster than it can be broken down or eliminated, its concentration can gradually increase.

Because moose are long-lived animals that consume large amounts of vegetation throughout their lives, analyzing their tissues can provide valuable information about long-term environmental exposure. Some substances may also accumulate differently in specific organs. For example, the liver and kidneys can provide different information than muscle tissue because these organs process, filter, and store substances within the body.

Age is also important when studying bioaccumulation. Comparing tissue results with the estimated age of each moose can help researchers determine whether concentrations of certain elements increase over an animal's lifetime.

Understanding bioaccumulation helps AITRC investigate connections between environmental conditions, wildlife health, and subsistence food resources in Ahtna Territory.

Tsin'aen!

Tsin’aen to the hunters, families, and community members who contributed samples to this project. Your participation made it possible to build a valuable dataset on moose health across the Ahtna Territory. AITRC is no longer collecting hunter-harvested moose samples for the Moose Toxicology Project. Samples contributed by hunters between 2022 and 2025 created a valuable collection of biological information that can continue to be analyzed and interpreted. This data will help us better understand moose health and potential implications for subsistence food safety.

Emily Benson, 2024 Natural Resource Technician, and Tamra Jones, UAF Master's Student, collect a sample from a hunter harvested moose

Ecologist, Kelsey Stanbro, and Master's Student, Tamra Jones, traveled to Texas A&M to process 2022 and 2023 samples

Sean Cotteleer, 2023 Fish and Wildlife Technician, removes teeth from a moose. Teeth help us age the moose.

Did you know?

A moose’s age can be determined by counting tiny annual layers in its teeth—much like counting rings in a tree! Dendrochronology is the science of counting growth rings to estimate age—most commonly in trees. For moose, we use the same idea, but instead of tree rings, we look at annual layers in a moose’s teeth to determine age.

As a moose grows, its teeth record time in a reliable way. A thin layer of tooth material (called cementum) builds up over the years in distinct annual bands—similar to rings in a tree. By counting these bands under a microscope, biologists can estimate the animal’s age.

Just like tree rings can be influenced by growing conditions, the wear patterns and annual layers in teeth can be affected by things like: