Authorities have scooped, blasted and vacuumed as they removed tonnes of dead sardines from a south California marina before the fish rot and possibly poison remaining sea life in the harbour.
The cleanup came after the enormous school of sardines apparently suffocated in the confines of King Harbour, possibly while seeking shelter from a predator or simply becoming lost near a breakwater late on Monday.
Instead of leaving, the fish crowded towards the back of the Redondo Beach marina and used all the oxygen in the water, marine experts have said.
A fire boat experimented with possible ways of retrieving the silvery corpses carpeting the bottom of the marina, including blasting them with a fire hose so they popped to the surface, police sergeant Phil Keenan said.
"Some places, we have upward of two feet of dead fish on the bottom," he said.
State department of fish and game officials sent samples of the fish to a lab to determine why they died, and strongly suggested the fish just got lost before landing in the marina.
Oxygen levels remained low in the stagnant water of the marina, and there was concern that unless the fish were collected within a few days, they would begin to decompose and release ammonia that could poison fish, crustaceans and other sea life.
Additionally, bacteria feeding on the bloated fish corpses could multiply and further deplete the oxygen.
"The smell in three days is going to be horrendous," warned a local fisherman.