Adult Patagonian toothfish reach lengths of up to 7.5 feet (more than 2 m) and weights of 220 pounds (100 kg). These large adults live near the bottom of the sea, 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.

Fun Facts about Patagonian Toothfish

1. Patagonian toothfish are bottom-dwelling species and can live at depths of up to 3000 meters.

2. The name “Chilean sea bass” was coined in 1977 to try to make the Patagonian toothfish more attractive to seafood consumers.1

3. The slow reproductive rate and long lifespan of the Patagonian toothfish make it particularly vulnerable to overfishing.2

4. The Patagonian toothfish is known as “white gold” in the commercial fishing industry due to the high prices it can fetch on the market.

5. The Patagonian toothfish’s diet mostly consists of squid, crustaceans, and other fish.

Engage Youth with Sailors for the Sea

Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.

Additional Resources:

1. One World One Ocean

2. UN Food and Agriculture Organization