Millions of fish found dead at California harbour

Scientists are working to determine the reason for the steep drop in oxygen levels in the water at King Harbor in Redondo Beach.

Millions of fish, mostly silvery sardines, apparently suffocated and lay floating as a silver sheen of carcasses among docked boats, a report in the Los Angeles Times said.

Hundreds of thousands of more fish are piled on the harbour`s bottom, 18 inches deep in some spots.

Cleaning up the harbour could take a few weeks and authorities fear in the meantime the dead fish could leave a foul stench.

"It appeared that a massive, churning ball of sardines, and some mackerel and anchovies, was chased toward shore over the last few days, primarily from a spring storm that brought wind gusts of 45 miles per hour off the coast last weekend," the report said.

Authorities and dozens of volunteers skimmed floating sardines from the water. They will be recycled and turned into fertilizer. The harbour is about 22 feet deep and there was not enough oxygen to support such a massive influx of fish.

A strong tide caused by the storm could also have pushed the fish into the corners of the marina, the report added. LA Conservation Corps` Sea Lab Programme director Brent Scheiwe said oxygen levels in the harbour are typically eight parts per million.

While three parts per million is considered critically low, the water in the harbour was at a below-lethal level of 0.72 parts per million.

"The levels were critically low," he said. "There was pretty much no oxygen in the water." State wildlife officials have sent a batch of the fish to Sacramento for chemical analyses.

The researchers have not found any trace of toxins, oil slick or algae buildup.

"It is naturally occurring, but an unusual event. It`s just a mess," California Department of Fish and Game spokesman Andrew Hughan said.

Similar massive fish kills have been reported in the King Harbor in 2003 and 2005 mainly due to algae buildup.