BOATERS IN A Southern California marina awakened yesterday morning to find a silvery carpet of about one million sardines packed who had perished overnight.

The fish stacked between 12- to 18-inches deep in some spots. The fished died when they apparently depleted the water of oxygen and suffocated after getting lost in the marina, officials said. Despite a daylong effort on Tuesday to scoop up fish in nets and buckets, the cleanup can take up to a week and the smell is  expected to get a whole lot worse.

“All indications are it’s a naturally occurring event,” said Andrew Hughan, a California Fish and Game spokesman. He said that the die-off was unusual but not unprecedented. ”In the world of fishing, this is an afternoon’s catch”.

The scale was impressive to locals at King Harbor Marina, which shelters about 1,400 boats on the Los Angeles County coast.

“The fishermen say they’ve never seen anything this bad that wasn’t red tide,” Hughan said, referring to the natural blooms of toxic algae that can kill fish.

Hughan said water samples showed no oils or chemicals that could have contributed to the deaths. He said some of the fish were being shipped to a Fish and Game laboratory for study but the cause was likely to be uncomplicated.

The fish appeared to have come into the marina during the night and probably got lost, he said. The 30-foot-deep marina simply couldn’t provide enough oxygen for such a massive influx of fish.

Two tests of some of the water on Tuesday showed oxygen levels near zero.

Additional reporting by AP