Oh, alright, I made up the hippie-hating part, but they do exhibit "cannibalistic" behavior, and they are quite large. Mexican fisherman call them "red devils."
Here in the US, we call them Humboldt Squids, and here's a short video about an ongoing invasion, from QUEST, a science show produced by San Francisco's PBS affiliate station.
A mysterious sea creature up to 7 feet long, with 10 arms, a sharp beak and a ravenous appetite, has invaded ocean waters off Northern California. Packs of fierce Humboldt Squid attack nearly everything they see, from fish to scuba divers. Marine biologists are working to discover why they've headed north from their traditional homes off South America.