Temperature also seems to affect the squid's buoyancy mechanism. Warm water will cause a giant squid to rise to the surface and not be able to get back down. With water temperature even higher at the surface, the squid maybe doomed. It is not surprising then, that most squid groundings occur near where two ocean streams, one cold and one warm, meet. A peice of sperm whale skin damaged by squid suckers in a life and death battle.
Estimates based on damaged carcasses range up to one hundred feet.
One story, though, suggests they might get even larger. One night during World War II a British Admiralty trawler was lying off the Maldive Islands in the Indian Ocean. One of the crew, A. G. Starkey, was up on deck, alone, fishing, when he saw something in the water. As I gazed, fascinated, a circle of green light glowed in my area of illumination. I suddenly realized was an eye.