The six sea lions found dead in traps near a Columbia River dam were apparently not shot to death after all, federal officials said Wednesday, leaving unanswered how the animals died or whether humans killed them.
Federal fisheries spokesman Brian Gorman in Seattle said preliminary results of a necropsy found no evidence of recent gunshot wounds but found shallow puncture wounds in one of the protected animals consistent with sea lion bite marks.
The fisheries department is still trying to determine how the animals died and how the doors to the traps in which they were found had been closed, he said.
Fishermen and American Indian tribes have long complained that the animals gobble up salmon at the base of the Bonneville Dam. Trapped sea lions identified as troublemakers were in the process of being sent to aquariums such as Sea World when the carcasses of the six animals were found over the weekend.
Because the first examination turned up no slugs, investigators had believed the animals were shot at close range with high-powered rifles, the bullets passing through the flesh.
X-rays on Tuesday found metal fragments in soft tissue near the neck of two animals, Gorman said. A metal slug was found in the blubber of one animal. But neither the fragments nor the slug appear to have caused fatal wounds and may have been from old injuries, he said.
The sea lions included two endangered Steller sea lions and one California sea lion pup.
The Humane Society of the United States, which is suing to block the authorized killing or removal of up to 85 animals a year for five years, agreed Tuesday with the federal government and the states of Oregon and Washington to continue a ban on killing and stop the animals' permanent removal until next year.
The move was in part to allow more efforts to go toward investigating what was thought to be shooting of the animals over the weekend.
The agreement allowed the governments to continue removing animals and branding them for identification if they return them to their natural habitat.
Arguments were to have been heard before a panel of the 9th U.S. Circuit Court of Appeals on Thursday.
Under the agreement, a hearing on the sea lions would be expedited, but killing or permanent removal could not take place until then, probably early next year.