Sardine Fish Kill in Redondo Beach California

In California, State biologists are running tests on a dozen dead fish from the Redondo Beach Harbor to determine the cause of a massive fish kill.

Approximately one million dead sardines were discovered in the Redondo Beach harbor on Tuesday morning, March 8, 2011. The event raised concerns about possible water contamination, which prompted officials to test local waters. Water samples tested on-site Tuesday were clear of contamination.

California Department of Fish and Game (DFG) wardens also sent about a dozen dead fish to the DFG laboratory in Rancho Cordova, where biologists will run tests to confirm that the die-off was not due to toxins in the water.

Because all the dead fish were contained in one area of the harbor, officials believe that the most likely culprit was oxygen deprivation. Recent storms could have caused the school of sardines to swim around the breakwater and into the enclosed harbor, where they were trapped and unable to get out before depleting the water of oxygen. According to biologists, oxygen-related fish kills can happen under these conditions.

The city of Redondo Beach activated its crisis response team Tuesday and by noon, more than 50 volunteers were assisting with the clean up. Dead fish were transported to a collection center, where they will be recycled into fertilizer. The harbor remains open.

Biologists at the northern California laboratory expect to complete their testing by mid-March, and DFG plans on continued monitoring of the harbor.