They sound like the invention of a B-grade horror movie: creatures that are intelligent, can grow as long as 8 feet, have razor-like tentacles, sharp beaks and ravenous appetites. But jumbo flying squid are no fantasy, and they began invading the shores of California this week by the thousands, according to the Los Angeles Times.

Also known as Humboldt squid, jumbo squid or "Diablo Rojo" (Red Devil) due to their reputation for attacking divers, these mysterious predators are usually native to the warm waters off the coast of Mexico, Central and South America, but for the last decade have occasionally migrated northward.

More than 1,000 jumbo flying squid have been caught since late last week, prompting concerns that this season's rising ocean temperatures due to the El Niño effect could lead to a squid invasion unparalleled in nearly a decade. Aside from frightening divers, the invasive squid are also a major threat to California's fishing industry. Known for being voracious hunters, the squid prey on just about everything that swims, including sardines, anchovies, hake and rockfish.

"Hake has been clobbered, apparently, by these squid," said Bruce Robison, senior scientist at the Monterey Bay Aquarium Research Institute. "Its decline exactly matches [the squid's] rise."

In order to compete, a number of fishing boat operators in California have been adding nighttime voyages. But the additional moonlit expeditions aren't designed to catch traditional fish at odd hours — they are designed to turn the hunters into the hunted. Jumbo squid, it turns out, make a tasty calamari steak.

"When they're lifted out of the water ... they become a giant squirt gun," said Robert Woodbury, a Newport Beach fisherman. "Chances are you're gonna take a faceful or a chestful of water — and probably ink — when you pull them out."

While they aren't easy to pull out of the water, this is one sea monster you don't want to encounter in the water either. In Mexico, tales of fishermen falling overboard in squid-patrolled waters and never being heard from again are legendary. Divers who have encountered jumbo squid have even occasionally been attacked or had their masks torn off.

Since they are equipped with tentacles with razor-sharp suckers, a parrot-like beak and fast movements, they can do some damage. John Field, NOAA research fisheries biologist, described the feeding behavior of the jumbo squid to KQED TV reporters as akin to eating corn-on-the-cob.

Furthermore, their behavior while feeding often extends to cannibalism, and they readily attack injured or vulnerable squid of their own shoal. But because the squid usually thrive in oxygen-depleted deeper waters, only returning to shallower seas at night, relatively little is known about them.

Experts believe, however, that these squid are particularly well-adapted to a warming climate. As climate change strengthens and offshore ocean habitats continue to struggle with oxygen-minimal "dead zones", they are likely to become an increasingly common visitor to California's coastal waters.

For more information on the jumbo squid invasion, check out this in-depth video report by KQED: