Cold temperate to sub-polar latitudes of the southern hemisphere
Soft bottoms from shallow continental shelves to the deep sea
Order Nototheniiformes (icefishes), Family Nototheniidae (cod icefishes)
The Patagonian toothfish is a relatively large species of deep-sea predator that gets its name from the region where it was discovered (Patagonia, South America) and its strong, pointy teeth. In markets and restaurants, it is typically marketed as Chilean seabass. Much like the orange roughy, this species’ name was changed to make it more favorable for seafood buyers. When it was being developed as a high value fisheries species, seafood distributors assumed that people would be more likely to buy a fish named Chilean Seabass than one with an intimidating name like Patagonian toothfish.
Adult Patagonian toothfish reach lengths of up to 7.5 feet (more than 2 m) and weights of 220 pounds (100 kg). These largest adults live near the bottom, in very deep water (over 12,000 feet/3800 m), where they hunt other fishes, squids, and crustaceans. They are known to be the occasional prey of deep-diving mammals like sperm whales and southern elephant seals. This species reproduces via broadcast spawning, where several females release their eggs and several males release their sperm into the water column at the same time. This method increases the likelihood that eggs will become fertilized and increases the genetic variability in the population. Patagonian toothfish are relatively slow to mature, with individuals becoming reproductively active at 8-10 years old.
The conservation status of the Patagonian toothfish has not been determined by scientific experts, but it is well known that several populations have been depleted by industrial fishing. The relatively low reproductive rate and late age at maturation cause this species to be vulnerable to overfishing, and without careful management of the fisheries targeting this species, it could soon reach a point of being vulnerable to extinction.
Note on a related species: The Antarctic Toothfish (Dissostichus mawsoni) is closely related to the Patagonian toothfish, is the target of a growing industrial fishery, and is often also marketed as Chilean Seabass. Without detailed labeling, it is difficult or impossible to determine which species a consumer is buying when simply labeled “Chilean Seabass.” The Antarctic Toothfish, however, is considered to be a well-managed fishery and is a more sustainable alternative to its Patagonian sister. Therefore, it is important to be able to distinguish between the two species. Like many Antarctic fishes, the Antarctic Toothfish has special proteins in its blood that prevents it from freezing in sub-zero temperatures.