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

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.