The Patagonian toothfish, Dissostichus eleginoides, also known as Chilean sea bass, is a deepwater (50-3000 meters) fish found on seamounts and continental shelves of oceans in the southern hemisphere. A slow-growing fish, it lives up to 50 years feeding on invertebrates and fish, and can reach 200 kilograms. Dissostichus eleginoides grows slowly, taking up to nine years to reach sexual maturity. It has a low fecundity and a long population doubling time (4.5-14 years). This is a species particularly vulnerable to overfishing. The Patagonian toothfish fishing industry is very lucrative as the fish fetch high prices, and Dissostichus eleginoides is an important commercial species for many countries, including Chile, Argentina, and the Falkland Islands. Illegal fishing in the 1990s has reduced population numbers but deep-sea “pirate fishing” is not easily regulated. Patagonian toothfish is known to be eaten by sperm whales, and also may make up 98% of elephant seals diet. The Monterey Aquarium and Greenpeace in addition to other organizations, have listed Dissostichus eleginoides as fish to avoid eating for overfishing reasons (unless certified as part of the small sustainable catch regulated by the Marine Stewardship Council). Patagonian toothfish also it is also listed by the Environmental Defense Fund as having high mercury levels.

(Catarci 2004; Environmental Defense Fund; Greenpeace; Monterey Aquarium; Wikipedia 2011)