Dozens of Jumbo Squid Beached After Quake--Coincidence?

Ker Than
for National Geographic News
July 14, 2009
Residents near a San Diego-area beach awoke to find dozens of jumbo squid, also called Humboldt squid, flapping helplessly on the shore Saturday—about an hour after an earthquake had struck off the California city at 7:34 a.m.

Raw Video (La Jolla, California, July 11, 2009)

According to local news reports, some beachgoers in the city of La Jolla attempted to throw the squid back into the water to save them from circling seagulls.

The mysterious jumbo squid stranding and the earthquake, though, are probably linked only by coincidence, experts say (jumbo squid picture wallpaper).

For one thing, scientists began finding beached squid at least three days before the Saturday earthquake, said squid expert William Gilly of Stanford University's Hopkins Marine Station.

"So unless the squid were predicting the earthquake, I don't think there's any link," he added.

(See "Can Animals Sense Earthquakes?")

Giant Squid Impervious to Quakes?

Jumbo squid can grow up to seven feet (two meters) long and weigh as much as 100 pounds (45 kilograms).

Biologists don't know of any squid bodily functions that would be affected by an earthquake. Unlike fish, for example, squid do not have air bladders, which can conceivably be compressed by an earthquake's seismic waves.

"It's hard to absolutely rule out, but it seems unlikely to me" that earthquakes could affect squid, said Danna Staaf, a Stanford marine biologist currently conducting research close to the squid stranding location.

Squid Stymied by Change in the Water?

Jumbo squid strandings have been seen around San Diego before.

In July 2002 thousands of the blue-red creatures washed onto area beaches. In the following months similar mass strandings were reported all along North America's Pacific coast, as far north as Alaska.

Like whale and dolphin strandings, the causes of squid beachings are a mystery.

"We've got a couple of ideas, but basically we don't know," Staaf said.

One theory is that the squid can be disoriented by rapidly changing water temperatures.

"The water temperature [around La Jolla] has been a little weird lately," Staaf said. "If the squid were in really warm water, but then it suddenly got very cold, that could be confusing for them."

Another possibility is that the beached squid had ingested dangerous amounts of a toxin called domoic acid. Produced by ocean plankton, the toxin can become concentrated in squid prey.

Staaf and her colleagues have collected the bodies of some of the stranded squid and plan to study their stomach contents.

"We're going to try to figure out if there's toxin in them."

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