Saga of the sardine apocalypse: why they died

Glenda Kwek
March 10, 2011 - 4:39PM

A "sardine apocalypse" in which at least one million dead fish were found floating in a harbour near Los Angeles on Tuesday may have been caused by a predator, strong winds or the fish simply getting lost, marine experts say.

Firefighters sank hoses to blast the fish to the surface while others vacuumed the carcasses and scooped them into dumpsters today in a clean-up estimated to cost about $US100,000.

The fish - mostly sardines but also mackerel and anchovies - had crammed into King Harbour at the back of Redondo Beach marina, reducing the oxygen supply in the water from eight parts to 0.7 parts per million, Redondo firefighter Pete Villasenor told local news website patch.com.

Without enough oxygen and as the tide went out, the fish died of suffocation.

"Everybody said it sounded like hail - all of the fish gasping for air," Bill Smythe, a sailor whose boat was parked in the marina, said.

At high tide, the harbour is only 6.7 metres deep. The fish were found about 30 centimetres deep on the beach and floating on the marina. Their deaths were labelled the "sardine apocalypse" and looked "as if Davy Jones himself had burped up a couple hundred years worth of lunches", the Los Angeles Times said.

The owner of a local fish bait shop, In-Seine Bait Co, Larry Derr, said the sardines were likely to have been preyed on by mackerel he had seen crowding the channel nearby a few days before.

There were so many mackerel that "guys were able to scoop them by hand".

"Chances are, between the mackerel and the seals, they kind of got cornered. And when the tide started going out - end of story."

Mr Villasenor said gusty winds may have been a factor, with fish scrambling for shelter on Monday night.
"It's like having a bunch of people falling into a cave and they can't breathe," he said.

"Here's what we know for sure. There was serious storm and wind activity for about a day and a half, gale force winds over 40 mph. They started making their way along and they found safe refuge in the harbour.

"Once that happened, they thought they had it made. They're pretty tired. They've realised it was a dead end. At that point they're trapped. They don't know how to get out. They suffocate. ... They ran [10 kilometres] as hard as they could and ended up in a cave and they're suffocating from their own carbon monoxide [sic]."

But Mr Derr cast doubt on the theory, saying fish usually swim deeper when there was bad weather.

"They're not walking on the water. Fish can handle the wind."

The California Department of Fish and Game, which sent samples of the dead fish to a lab for autopsies, believed the sardines simply got lost.

Spokesman Andrew Hughan said no chemical spills or oil sheens had been found.

"It is a naturally occurring - but unusual - event. It's just a mess," he told the Times.

Earlier theories that the fish were swimming away from a toxic algae bloom were abandoned after experts said there was no "red tide" in the area.

As officials and locals removed the fish from the harbour as quickly as they could - to prevent their decomposition from attracting bacteria that will take up more oxygen and threaten the survival of other marine life, sea lions and seagulls feasted on the fish.

"They are sitting there fat and happy," Mr Derr told the Times. "They don't know what to do with themselves; there are thousands of them."

Meanwhile in Spain, revellers were ceremonially carrying a small coffin containing a mock sardine on the streets as part of the annual "Burial of the Sardine" funeral procession, which is held in celebration of the countdown to Lent.

See photos at: http://www.smh.com.au/environment/animals/saga-of-the-sardine-apocalypse-why-they-died-20110310-1bpa1.html
(Submitted by Rebecca Lang)