Goliath groupers can grow to 800 pounds and nine feet long. That’s big enough to drag a spear fisherman, like the man in this video, who loses his temper when his parrotfish catch is snatched away by a goliath. “What is a grouper supposed to do, anyway, when a fish is injured in the neighborhood?” says oceanographer and National Geographic Explorer-in-Residence Sylvia Earle. “Dinnertime!” The incident took place at a shipwreck in the northern Gulf of Mexico. Goliath groupers often gather at shipwrecks and reefs to eat and socialize.