From Amber the biologist for the lake regarding the dead catfish.

"Since it is only affecting the bullheads that it is probably due to the lake turning over and anoxic conditions in a portion of the water column. This has happened a couple of times to the Kokanee over at Stampede in the fall. The lake will turn over and fish that reside at different depths will struggle if their portion of the water column has little to no oxygen."

She is also collecting some of them to take to the Rancho Cordova DFW office to be examined.