The mysterious deaths of dozens of giant sturgeon in the Columbia River near the Tri-Cities is prompting state officials to consider closing catch-and-release fishing of the species.
Paul Hoffarth of the state Department of Fish and Wildlife says people have reported finding more than 80 dead sturgeon on the river from the Hanford Reach to Boardman, Oregon.
The Spokesman-Review reported all the fish were in the large category, ranging from 5 feet to 8.5 feet long.
Hoffarth says theories for the sturgeon deaths include the possibility that the sockeye salmon they’re eating could be diseased from migrating upstream in the Columbia’s unusually warm water.
He says another theory suggests the sturgeon are stressed by the combination of dramatically lower flows with higher-than-normal July water temperatures.
Read more: http://www.king5.com/story/tech/science/environment/2015/07/16/officials-worried-by-mysterious-deaths-of-sturgeon/30270195/