The United States Fish and Wildlife Service said on Monday that a seismic survey planned for the Arctic National Wildlife Refuge in Alaska this winter would have “no more than a negligible impact” on the numbers of polar bears in the region.
The finding was contained in a proposal by the agency to allow up to three incidents in which bears could be inadvertently harassed or disturbed during the survey work, which would take place over several months and is meant to detect signs of oil and gas reserves underground.
The agency said that a few incidents of unintentional harassment, by, for example, coming too close to a bear and causing it to flee or interrupt feeding, would not affect survival. It added that it did not expect any bears to be physically injured or killed during the survey.
The proposal is to be published in the Federal Register on Tuesday, after which the public will have 30 days to comment. Approval after the comment period would remove a major hurdle to allowing the survey to begin early next year.
The project, which has been proposed by an Alaska Native village corporation, would involve heavy trucks and other equipment rolling across the snow-covered tundra in one part of the refuge, the coastal plain along the Beaufort Sea.
Polar bears are listed as threatened under the Endangered Species Act. With climate change reducing the extent of sea ice, their main habitat, the subpopulation in the southern Beaufort Sea declined by about 40 percent from 2001 to 2010. There are currently thought to be about 900 animals in the subpopulation.
Sea-ice loss has meant that more of the bears come onto land for longer periods. Pregnant bears, in particular, often build winter dens in the snow of the coastal plain where they give birth to cubs and nurse them during their first few months of life.
Robert Dewey, a vice president of Defenders of Wildlife, said that detecting polar bears in their dens can be very difficult. “But that isn’t stopping developers from pursuing oil and gas exploration there,” he said in criticizing the Fish and Wildlife Service proposal.
The Arctic refuge, one of the last great expanses of unspoiled land in the United States, has long been protected from oil and gas development. But in 2017, the Trump administration and Republicans who controlled Congress removed protections for 1.5 million acres of the coastal plain.
Since then the White House has been pushing forward with a plan to allow oil and gas drilling there. The polar bear proposal is another sign that those efforts have accelerated in recent weeks following President Trump’s re-election defeat.
Last week, the Bureau of Land Management announced a plan to sell oil and gas leases in the coastal plain on Jan. 6, two weeks before the inauguration of Joseph R. Biden Jr., who opposes drilling in the refuge.
Separately, the bureau is preparing an environmental assessment of the planned survey. A spokeswoman for the bureau said the assessment should be available “relatively soon” and would be followed by a comment period before the bureau makes a final decision on whether to allow the survey to proceed.
Assessing the potential effect on polar bears had been something of a stumbling block to approving a seismic survey in the refuge. A previous proposal, put forth in 2018, was ultimately shelved as an environmental assessment and work on determining the impact on polar bears dragged on.
Under a federal law designed to protect polar bears and other marine mammals, the Interior Department, of which the Bureau of Land Management and the Fish and Wildlife Service are a part, can authorize “incidental harassment” of a small number of animals during activities in an area like a refuge. An authorization usually involves lengthy discussion and negotiations between government scientists and those proposing the activity.
In its application, the Native village corporation that proposed the survey, the Kaktovik Iñupiat Corporation, said it would take several steps to detect bears in their dens and avoid contact with them, including reconnaissance flights in late January, before any trucks begin operating. Such flights would use infrared cameras to detect heat from bears.
Survey crews would then establish a one-mile buffer zone around each den to avoid disturbing the bears and perhaps causing them to leave their dens, which could threaten the survival of the cubs.
A study published this year questioned the effectiveness of airborne thermal cameras. It found that over more than a decade using them on the North Slope of Alaska, oil companies located fewer than half of the known dens of maternal bears and their infant cubs.
The village corporation’s proposal originally called for a single reconnaissance flight. But the Fish and Wildlife Service said that the proposal now included three flights, all of which would occur before trucks entered the refuge. On average, dens on the coastal plain are covered by less than 100 centimeters, or about 39 inches, of snow, the service said, and having three flights “increases the likelihood of detecting dens at less than 100 cm deep to 98 percent.”
Environmental groups have also objected to the plan for a seismic survey because of the potential damage heavy trucks could do to the delicate Arctic tundra, even under snow cover. Tracks from the only other survey conducted there, in the 1980s, are still visible today.