A new study has claimed that the research done by the US Department of the Interior to determine if global warming threatens the polar bear population is so flawed that it cannot be used to justify listing the polar bear as an endangered species.
The research came about when on April 30, US District Judge Claudia Wilken ordered the Interior Department to decide by May 15 whether polar bears should be listed under the provisions of the Endangered Species Act.
But, after professor J. Scott Armstrong of the Wharton School and colleagues undertook an audit at the request of the state of Alaska, they found the Interior Department report to be flawed.
As part of the subsequent study, the authors examined nine US Geological Survey Administrative Reports.
Professor Armstrong and his colleagues concluded that the most relevant study, properly applied only 15% of relevant forecasting principles and that the second study only 10%, while 46% were clearly contravened and 23% were apparently contravened.
Further, according to them, the Geologic Survey reports do not adequately substantiate the authors' assumptions about changes to sea ice and polar bears' ability to adapt that are key to the recommendations.
Therefore, the authors write, a key feature of the US Geological Survey reports is not scientifically supported.
The consequence, they maintain, is significant: The Interior Department cannot use the series of reports as a sound scientific basis for a decision about listing the polar bear as an endangered species.
According to Armstrong, to list a species that is currently in good health as an endangered species requires valid forecasts that its population would decline to levels that threaten its viability.
In fact, the polar bear populations have been increasing rapidly in recent decades due to hunting restrictions.
Assuming these restrictions remain, the most appropriate forecast is to assume that the upward trend would continue for a few years, then level off.
"These studies are meant to inform the US Fish and Wildlife Service about listing the polar bear as endangered," said Armstrong.
"After careful examination, my co-authors and I were unable to find any references to works providing evidence that the forecasting methods used in the reports had been previously validated. In essence, they give no scientific basis for deciding one way or the other about the polar bear," he added.