Initial probe blames overheating for Oregon sea lion deaths

PORTLAND — The deaths of federally protected sea lions found in traps at Bonneville Dam on the Columbia River may be due to overheating.

Government wildlife specialists made that conclusion after their review of the necropsies conducted on the six protected sea lions.

Studies of tissue samples taken after the May 4th deaths are expected in about 10 days and may reveal more.

The states of Oregon and Washington had been trapping the animals as part of a federally approved removal process to reduce sea lion impact on salmon at the dam.

The Humane Society of the United States questioned Wednesday whether the 60-degree weather at the time would kill animals that can survive worse.