The largest toothed predators in the world, sperm whales are the giant squid’s main nemeses. Their stomachs have been found full of the squid’s parrot-like beaks, and their heads often bear circular scars inflicted by the serrated rims of the squid’s suckers. They do not produce their own light, but just like a descending submersible, they trigger flashes of bioluminescence when they bump against small jellyfish, crustaceans, and other plankton.
