.png)
Bear Study
Understanding how many black and brown bears live across the Ahtna Territory is essential for responsible wildlife stewardship, community safety, and informed harvest management. Through non-invasive genetic sampling and collaboration with partners, AITRC is working to quantify bear populations across Game Management Units 13 and beyond.
“Why would we sell permits for bear-baiting when we don’t know how many bears are on the land?”
This project began with a powerful question from an Ahtna Elder. That question sparked a multi-year collaborative effort to estimate black and brown bear populations across the Ahtna region. In 2021 and 2022, the Ahtna Intertribal Resource Commission (AITRC) partnered with the Alaska Department of Fish & Game (ADFG), Ahtna Inc., and the University of Alaska Fairbanks (UAF) to conduct one of the most comprehensive non-invasive bear studies in the Upper Copper River Basin.
Black and brown bear populations are difficult and expensive to estimate. Advancements in genetic testing provide AITRC the opportunity to identify individual bears to the species level using hair samples collected from hair snares and samples saved from hunter-harvested bears. These samples allow us to establish density and abundance estimates using spatially explicit mark-capture-recapture (SECR) methodology.
Hair Snare Deployment.
The project utilizes a noninvasive hair snare cluster design to estimate black and brown bear populations within Game Management Units (GMU) 13. Sampling efforts are clustered across the landscape, spacing of clusters and hair traps was based on the average home range of collared adult female brown bears from another ADF&G bear project.
Standard corral-style barbed wire hair snares are deployed to collect hair samples when adequate trees were in the area of interest. Barbed wire is strung around trees or posts so that tufts of hair are collected as bears pass over or under the wire to access bait placed in the center of the corral. Bears are attracted using scent lures, no food reward was provided to avoid trap-happy bears. In areas where no adequate trees exist, researchers built free-standing hair snares by hauling in precut spruce poles to erect structures to attach barbed wire to. Each barb is processed as an independent sample. GPS coordinates are recorded at each snare site, and locations are entered into a Geographic Information System for mapping and analysis.
Hair snares are deployed during five separate sampling periods over the course of the summer, occurring in May, June, July, and August. Each sampling period lasts two weeks, and sites were rebaited and/or moved every two weeks. Each new sampling period, the scents and lures were changed to ensure that if bears were in the area, they would continue to investigate the “new” sites.
Field Monitoring & Site Investigations.
All hair snare locations are recorded using GPS and mapped in GIS software. Camera traps were deployed at select sites to monitor bear movement patterns and reactions to the hair snare design. Technicians navigate remote terrain to check sites and collect samples safely and consistently. This is paired with hunter harvest data to estimate the density and abundance of black and brown bears within the Ahtna region
Why this matters?
Estimating black and brown bear populations is a necessary component of understanding the broader ecosystem in which bears function as apex predators. Reliable population data provides critical information for evaluating predator-prey dynamics, particularly in relation to concerns about low moose numbers within the region. Without accurate estimates of bear abundance and density, wildlife management decisions are made with a limited understanding of population structure and distribution.
The information gathered through this project helps address existing data gaps between the State of Alaska and the National Park Service bear population datasets. Increasing the availability of region-specific data strengthens management decisions and improves coordination among agencies and landowners operating within the Upper Copper River Basin.
For Ahtna communities, abundance and density estimates are also directly connected to village safety and responsible harvest management. Maintaining a healthy and sustainable bear population while continuing to allow quality hunting opportunities on Ahtna lands requires informed, science-based decision making.
Ahtna people have long served as stewards of the land. Developing reliable bear density and abundance estimates represents an important step in continuing that stewardship by integrating genetic science, field research, and Indigenous knowledge to guide long-term wildlife management across Ahtna Territory.
Luke Porter and Petros Platis, 2021-22 wildlife technicians, flew into Tazlina Lake where they boated around setting up sites for the Bear Hair Snare project
.jpg)
Damien James, 2022 wildlife technician, is hard at work recording all of our data for our bear project!
.jpg)
Jessy John, 2021 wildlife technician, setting up a freestanding bear hair trap to collect samples for genetic analysis