© Kt Miller/Polar Bears International
9/20/2018 4:22:00 PM
New Projects in Russia
By Geoff York, Senior Director of Conservation
Take a look at a population status map for polar bears and you can’t help but notice that the entire Russian coast is marked as “data deficient.” In fact, the vast Russian Arctic contains the least studied polar bear populations in the world.
It’s easy to see why. Conducting research in the Russian Arctic is logistically difficult and historically quite expensive. Basic infrastructure—including small aircraft and reliable fuel depots—are often lacking or restricted. In addition, many of Russia’s polar bears are shared with other countries. This creates additional challenges, from Internal security concerns to barriers posed by shifting international politics.
Despite these hurdles, recent partnerships and novel approaches have led to new opportunities.
In light of these developments, Polar Bears International is helping to fund two key research projects focused on polar bear populations shared by Russia and other countries, one in the Barents Sea and the other in the Chukchi Sea. Both are biologically rich areas thought to have large populations of polar bears. The studies will help scientists fill data gaps, leading to a better understanding of how these bears are faring.
Barents Sea Project
Russia’s Barents Sea polar bear population is shared with Norway. These bears have experienced a massive loss of sea ice habitat over the last few decades, a trend predicted to continue. A few hundred of the bears in this population remain in Norway’s Svalbard archipelago year-round. But the majority migrates between Svalbard, Russia’s Franz Josef Land, and the pack ice areas north of the islands.
Thanks to a long-term monitoring project by the Norwegian Polar Institute (NPI), the polar bears that range within Norway’s borders are well-studied, with data going back to 1987. However, very little is known about the Barents Sea bears that live in Russian waters.
This study will focus on whether the population is able to maintain its genetic diversity in the face of substantial sea ice loss. The NPI began collecting DNA samples from polar bears in Norway in 2003. Their initial research showed that:
- Most of Svalbard’s polar bears ranged in the same local areas over generations.
- Daughters usually chose maternity den sites in the same areas as their mothers. However, some looked for alternative den locations when the sea ice failed to connect more remote islands to the pack ice.
- Historically, close inbreeding has been rare, despite male and female polar bears remaining in local areas over generations.
- Females typically mated with different males, within a single year and over different years. This ensured high genetic diversity.
- Large-scale gene exchange between local Svalbard bears and migrating bears ensured a large effective population size.
Given the rapid changes in sea ice in Svalbard, scientists anticipate significant changes in mating systems, including increased local isolation and the possibility of decreased gene exchange between local and migrating bears. More restricted interaction between bears from different areas may lead to increased inbreeding.
This study will focus on answering those questions by analyzing DNA samples from polar bears in Norway, Russia, and Greenland.
Chukchi Sea Project
The Chukchi Sea polar bear population is shared by Russia and the United States. Although these bears roam freely between the two nations, scientists have long thought that most of the Chukchi Sea bears are born on Russia’s Wrangel Island or nearby Herald Island, a hypothesis recently supported by satellite data from U.S.-based research.
Given Wrangel Island’s importance, Dr. Eric Regehr of the University of Washington is spearheading a project there to restart basic monitoring and launch new research on the island. In concert with the U.S. Fish and Wildlife Service and Wrangel Park staff, Dr. Regehr led an expedition last fall to assess the potential for research on Wrangel and to support park staff in counting the number of bears onshore in the summer months.
This was the first of a planned three-year effort focused on observational surveys on land and the use of hair-snare boxes to collect genetic samples in a non-invasive manner. The data gained will help address key conservation challenges for the Chukchi population, including sea ice loss due to climate warming and increased industrial activity and shipping in the region. Efforts will also be undertaken to help park staff mitigate working in an area with a high probability of polar bear-human interaction. This work will include enhanced data collection on incidents, sharing of information regarding safety procedures, and sharing of potential conflict mitigation tools such as bear spray.
In 2017, the team completed the first year of fieldwork:
- From September 19th to October 9th, they conducted a ground-based observational survey of Wrangel Island’s polar bears, covering 900 kilometers. The survey was designed to sample important polar bear habitats in a systematic manner.
- The team observed 589 individual polar bears during the survey. To their knowledge, this was the largest number of bears recorded on Wrangel Island, possibly indicating that sea ice loss in the region is driving more of the bears in this population ashore.
- For bears that could be individually evaluated, the estimated sex, age, and reproductive composition was 9 percent subadult, 23 percent adult male, 15 percent single adult female, 21 percent adult female with dependent young, and 34 percent unknown.
- The team deployed hair-snare boxes in 19 locations for approximately 35 trap-days, yielding 13 sets of hair samples. This suggests that hair-snare boxes are a viable method for collecting genetic samples from Wrangel Island’s polar bears.
The 2017 fieldwork reaffirmed the importance of Wrangel Island to the Chukchi polar bear population. Subsequent years of research, including work taking place this fall, will help scientists evaluate trends and better understand the health of this population.