Californian authorities have been left flummoxed, after millions of dead sardines washed up in a marina just south of Los Angeles.
The mass of fish, a third of a metre deep, prompted a massive clean-up.
It is thought the sardines may have suffocated after a storm drove them under a pier, where they used up all the oxygen.
Andrew Hughan, spokesman for the California Department of Fish and Game, said: ‘‘Our game wardens took a bunch of water samples and they just did a preliminary litmus test and pH test [for acidity or alkalinity] and the water is fine. It is exactly where it should be, the city is very confident that the water is completely clean.’‘
Biologists have yet to finish their inquiries. But, not everyone is convinced that the fish died of natural causes and some locals are fearing the worst.
‘‘Devastating, absolutely devastating. It is scary too because you see these seals coming in here and they are having a heyday in it and you wonder how it is going to affect them tomorrow or next week. It is a serious problem,’‘ one woman said.
Meanwhile, authorities are still deciding what to do with the fish. The clean-up is expected to take weeks and one option being considered is to dump them out to sea.