July 25, 2007 — Jumbo squid that can grow up to 7 feet long and weigh more than 110 pounds is invading central California waters and preying on local anchovy, hake and other commercial fish populations, according to a study published Tuesday.
An aggressive predator, the Humboldt squid — or Dosidicus gigas — can change its eating habits to consume the food supply favored by tuna and sharks, its closest competitors, according to an article published in the Proceedings of the National Academy of Sciences journal.
"Having a new, voracious predator set up shop here in California may be yet another thing for fishermen to compete with," said the study's co-author, Stanford University researcher Louis Zeidberg. "That said, if a squid saw a human they would jet the other way."
The jumbo squid used to be found only in the Pacific Ocean's warmest stretches near the equator. In the last 16 years, it has expanded its territory throughout California waters, and squid have even been found in the icy waters off Alaska, Zeidberg said.
Zeidberg's co-author, Monterey Bay Aquarium Research Institute senior scientist Bruce Robison, first spotted the jumbo squid here in 1997, when one swam past the lens of a camera mounted on a submersible thousands of feet below the ocean's surface.
More were observed through 1999, but the squid weren't seen again locally until the fall of 2002. Since their return, scientists have noted a corresponding drop in the population of Pacific hake, a whitefish the squid feeds on that is often used in fish sticks, Zeidberg said.
