A polar bear rests with her cubs on the pack ice in the Beaufort Sea in northern Alaska in this undated photo released by the U.S. Fish and Wildlife Service. The Interior Department's inspector general has begun a preliminary investigation into why the department has delayed for nearly two months a decision on listing the polar bear as threatened because of the loss of Arctic sea ice.

Washington ? The Interior Department’s inspector general has begun a preliminary investigation into why the department has delayed for nearly two months a decision on listing the polar bear as threatened because of the loss of Arctic sea ice.

A recommendation to Interior Secretary Dirk Kempthorne was to have been made by the U.S. Fish and Wildlife Service on whether to declare the bear threatened in early January. But when the deadline came, the agency said it needed another month, a timetable that also was not met.

A spokesman for the department’s inspector general’s office said a case had been opened in response to a letter from several environmental groups. He said the preliminary inquiry would determine whether a full-fledged investigation is warranted.

“The letter had specific allegations … (so) we started an initial inquiry,” said Kris J. Kolesnik, associate inspector general for external affairs. “If the initial inquiry produces something that warrants us to take further action, that’s when we open an investigation.”

Scientists have said the bear is under a growing threat because of the significant loss of Arctic sea ice because of global warming.

The Interior Department in early 2007 proposed listing the bear as threatened under the Endangered Species Act, triggering a year of scientific review. By law a recommendation was to have been made by the Fish and Wildlife Service by last Jan. 9, a year after the initial action.

The letter to Inspector General Earl Devaney, signed by six environmental groups, alleges that Fish and Wildlife Director Dale Hall violated the agency’s scientific code of conduct and the Endangered Species Act in delaying the decision after all of the scientific data had already been developed and sent to Washington before Christmas.

The code is aimed at preventing inappropriate political influence as the agency administers the Endangered Species Act. The code came into being because of another IG report that detailed widespread political interference on species protection decisions that led to the resignation of a senior Interior Department official last May.