U of I Research Team Identifies Polar Bears Using DNA Found in Paw Prints
August 17, 2023
MOSCOW, Idaho — Researchers at the University of Idaho have found a unique, non-invasive way to identify polar bears in the Arctic by scraping DNA from a bear’s paw print.
In the face of diminishing Arctic sea ice — where polar bears spend most of their time — scientists have been looking for ways to monitor the bears without buzzing them with helicopters, darting and handling them to gather data including DNA.
In a recent article, “Determination of polar bear (Ursus maritimus) individual genotype and sex based on DNA extracted from paw-prints in snow” in Frontiers in Conservation Science, section Animal Conservation, U of I researcher Jennifer Adams and Professor Lisette Waits and three co-authors from North Slope Borough Department of Wildlife and Alaska Department of Fish and Game show how scientists can identify individual polar bears by the stuff left in their tracks.
The “stuff” is polar bear DNA from epidermal cells bears leave behind in their tracks.
In Alaska, the researchers used trowels to scrape a thin layer of snow from fresh bear footprints. Then, in her Moscow, Idaho, genetics lab, Adams and her colleagues collected cells from the melted snow that made up the sampled polar bear tracks. The cells provide a DNA fingerprint of individual bears.
Of 15 samples collected, two contained no bear DNA, and 11 were positive for bear DNA. The technique is still at an experimental stage but, so far, has proven a non-invasive and cost-effective way to learn about bears in the wild.
Because polar bears occupy remote and environmentally extreme habitats, population monitoring for conservation and management is challenging, costly and becoming more difficult with rapidly changing environmental conditions.
“To our knowledge, this is the first time that polar bears, or any other species, have been individually identified and sexed using environmental DNA collected from snow,” Adams said.
Caption and credit information for attached photos are below.
- Trowel: Peter Detwiler, a wildlife field technician with North Slope Borough Wildlife Department, on the shorefast sea ice north of Utqiagvik, AK. Credit: Jennifer Adams.
- Paws: Polar bear footprints on the shorefast sea ice north of Utqiagvik, AK. Credit: Jennifer Adams.
- Jennifer: Jennifer Adams on the shorefast sea ice north of Utqiagvik, AK. Credit: Andy Von Duyke.
Lisette Waits Ph.D.
Distinguished Professor of Wildlife Resources
University of Idaho
About the University of Idaho
The University of Idaho, home of the Vandals, is Idaho’s land-grant, national research university. From its residential campus in Moscow, U of I serves the state of Idaho through educational centers in Boise, Coeur d’Alene and Idaho Falls, nine research and Extension centers, plus Extension offices in 42 counties. Home to nearly 11,000 students statewide, U of I is a leader in student-centered learning and excels at interdisciplinary research, service to businesses and communities, and in advancing diversity, citizenship and global outreach. U of I competes in the Big Sky and Western Athletic conferences. Learn more at uidaho.edu.