In the debate over the possibility of oil drilling in the Arctic National Wildlife Refuge in Alaska, polar bears play an important, if silent, role.
At issue is whether oil development, especially seismic testing to find oil reserves that would be conducted long before any drilling occurred, can be undertaken without harming the animals, which have been hit hard by climate change.
A new study casts doubt on the effectiveness of what is considered a state-of-the-art tool to help industry avoid injuring or disturbing polar bears by detecting their dens in the snow. Over more than a decade on the North Slope of Alaska, the study found, oil companies located fewer than half of the known dens of maternal bears and their infant cubs using airborne instruments called forward-looking infrared, or FLIR, cameras.
“We wanted to make sure that we throw up a cautionary flag,” said Tom Smith, a wildlife ecologist at Brigham Young University and the lead author of the study, which was published Thursday in the journal PLOS ONE. The oil industry “needs to acknowledge that even with the best conditions, you’re going to miss bears,” added Dr. Smith, who is also a scientific adviser to Polar Bears International, a conservation group that provided some of the funding for the study.
Pregnant polar bears dig dens in the snow late in the year and emerge with their cubs the following spring. Undetected dens could be disturbed or even crushed during a seismic survey, in which large trucks traverse the land in a grid pattern, accompanied by movable supply depots and camps for workers.
On the North Slope of Alaska, where oil drilling has been conducted since the 1970s, seismic surveys are only allowed in winter when there is enough snow to protect the delicate Arctic tundra.
FLIR cameras, which are carried by airplanes or helicopters, can detect heat under the snow. But Dr. Smith said weather conditions have to be just right — not much wind and little moisture — for the cameras to get good readings.
Other factors, like too much snow cover, can also cause the cameras to miss dens.
“If the snow overlying a den is more than a meter thick, FLIR is not going to see it,” Dr. Smith said. “The heat fritters away in the snowbank.”
Detection is likely to become more difficult as the Arctic continues to warm under climate change, as warmer air contains more heat-scattering moisture, he said.
Using industry reports of FLIR surveys from 2004 to 2016 and comparing them with on-the-ground documentation of dens across the North Slope, the researchers found that only 45 percent of the 33 dens were located by FLIR cameras. The surveys also produced a number of false positives, because sources like exposed soil and rocks or even discarded steel drums can radiate heat that might be interpreted as signs of a den.
The Arctic refuge is an important denning area for the Southern Beaufort Sea subpopulation of polar bears, one of the most threatened in the world. Reduction in sea ice coverage, a result of rapid warming in the Arctic, has led to a sharp decline in the population, as it has become more difficult for the bears to reach seals and other food at sea.
The potential harm to the bear population has become a major issue amid the Trump Administration’s efforts to allow oil drilling in the Arctic refuge, an area the size of South Carolina that is largely untouched by human activities.
A tax bill passed by Congress in 2017 allowed the Interior Department to develop plans for oil development in a part of the refuge along its northern coast called the 1002 Area. The administration had hoped to begin selling leases last year, despite opposition from Democratic lawmakers, threats of legal action by environmental groups and uncertainty about how much oil underlies the area. A New York Times investigation uncovered evidence that the only oil well ever allowed in the refuge, one that was drilled in the mid 1980s to look for signs of oil reserves, had disappointing results.
Lease sales were never conducted and the administration’s plan remains stalled. An environmental impact statement, required before sales can be held, has been prepared by the Interior Department but no final decision has been made.
Lesli Ellis-Wouters, a spokeswoman in Alaska for the Bureau of Land Management, the Interior agency that is managing the development of the leasing plan, said it was not uncommon for a final decision on an impact statement to be issued several months after the statement is finished. As for the status of the lease sales, she added, “By law, the first lease sale is required to occur before December 2021 and we are well within that time frame.”
A proposal for a seismic survey in the 1002 Area is also stalled. It was developed by SAExploration, a seismic services company based in Houston, and several Alaska Native corporations, and was criticized by environmental groups and even some Interior Department scientists as potentially harmful to polar bears. The department ordered an environmental assessment of the proposal, which is less comprehensive than an environmental impact statement.
Last week, Carol Danko, an Interior spokeswoman, said in an email that the “environmental assessment (EA) application is currently on hold at the preliminary draft stage pending updates to the plan of operations from the proponent.”
SAExploration did not respond to a request for comment. The company defaulted on some of its debt last summer and announced that it was under investigation by the Securities and Exchange Commission for its accounting practices. The company’s chief financial officer was fired and its chief executive resigned.
If a seismic survey does take place in the refuge, another paper, by Interior Department scientists, has suggested ways it could reduce disturbances to polar bears.
The study, published in December in The Journal of Wildlife Management, used computer simulations of survey designs that varied in where and when the seismic trucks rolled, to avoid known denning areas or survey them only after bears have emerged, usually in early March. It found that a survey design with the most specific restrictions on locations and times reduced the number of dens disturbed by more than 90 percent compared with a survey with no restrictions.
Ryan R. Wilson, a biologist with the United States Fish and Wildlife Service in Alaska and an author of the study, said it showed that “if you provide a lot of extra information, we can go a long way toward mitigating disturbance to polar bears.”
The study also showed that FLIR surveys could further reduce impacts on dens. Dr. Wilson said he was aware of the newer study that questions the effectiveness of FLIR surveys, but said his study also took into account their limited effectiveness.
The survey design study is currently open for a 60-day public comment period by the Interior Department, a rare action for an academic paper. Dr. Wilson said he did not know why the paper was opened for comment.
A Fish and Wildlife Service spokeswoman said that the comment period was “a way for us to make the public aware of the study and receive feedback on how we might apply the model in the field.”
An environmental group, Defenders of Wildlife, criticized the decision. “The study clearly shows a problem reconciling oil development and protecting these imperiled polar bears,” said Robert Dewey, the organization’s vice president for government relations. “The comment period gives industry an opportunity to try and discredit the study.”