Toothfish
A genus of large marine fish from the Southern Hemisphere, known commercially as Chilean sea bass.
Dissostichus comprises two species of deep-sea notothenioids found in cold southern waters. They are vital to their ecosystem and heavily fished for their oily white flesh, marketed under a famous trade name created in the late twentieth century.
- Marketing name Chilean sea bass created in 1977 by Lee Lantz.
- Adults can weigh more than one hundred kilograms.
- Patagonian toothfish lives up to fifty years.
- Ross Sea marine protected area established in 2016.
- Illegal fishing reduced by ninety percent through surveillance.
What it is
The toothfish belongs to the family Nototheniidae, commonly called notothens or cod icefish. This genus contains two recognized species: the Patagonian toothfish and the Antarctic toothfish. They are large ray-finned fish with scaleless patches between the eyes and distinct lateral lines. Adults can exceed one hundred kilograms in weight, a trait that separates them from other members of their family. Their bodies are adapted for life in the cold, dark depths of the southern oceans.
Where it lives
These fish inhabit the Southern Hemisphere, primarily around the Antarctic continent. The Patagonian toothfish ranges circumpolarly near the Antarctic Convergence across Atlantic, Pacific, and Indian sectors, with populations near South America. The Antarctic toothfish lives further south on the continental shelf and in the Ross Sea, generally below sixty degrees south latitude. Both species occupy deep benthopelagic zones, with Patagonian individuals found at six hundred to fifteen hundred metres and Antarctic individuals at thirteen hundred to nineteen hundred metres.
How it lives
Toothfish are carnivores throughout their lives. Juveniles feed on smaller notothenioids, krill, squid, and pelagic fishes. As they mature, their diet expands to include larger fishes, cephalopods, and crustaceans. The Patagonian species also scavenges remains sinking from upper waters. They serve as important prey for elephant seals, sperm whales, killer whales, and Weddell seals. Overfishing may impact these predator populations by altering food availability.
Breeding and life cycle
Both species migrate to shallower waters to spawn during the austral winter and early spring. The Patagonian toothfish spawns between June and September at depths of eight hundred to one thousand metres. Eggs develop over three months, hatching in October or November. Larvae drift planktonically until February before moving to deeper waters. The Antarctic toothfish likely spawns between June and November north of seventy degrees south, with eggs developing over four to five months.
Fish and people
The Patagonian toothfish is sold in the United States as Chilean sea bass, a marketing name coined in 1977 by wholesaler Lee Lantz. The FDA accepted this term in 1994. The fish became popular in restaurants due to its large size and white, oily flesh. Commercial fishing began in the 1970s as bycatch but expanded significantly after 1987. The Antarctic toothfish was also marketed under similar names after 2013. Illegal fishing has been a major issue, though international surveillance has reduced unregulated catches.
Status and threats
Conservation efforts are managed by the Commission for the Conservation of Antarctic Marine Living Resources. A large marine protected area in the Ross Sea was designated in 2016, banning most fishing until 2052. Some scientists worry about biomass estimations and illegal fishing activities. Environmental groups have placed Chilean sea bass on red lists, leading some retailers to stop selling it. Research suggests that sustainable management is critical for maintaining ecological balance in the Southern Ocean.
Questions people ask about Toothfish
What is Chilean sea bass?
It is a marketing name for the Patagonian toothfish, coined in 1977 to make the fish more appealing to American consumers. The FDA officially accepted this alternative market name in 1994.
How big do toothfish get?
Both species in the genus Dissostichus are large. Adults can exceed one hundred kilograms in weight, which distinguishes them from other notothenioid fish.
Where do toothfish live?
They are found in the Southern Hemisphere. The Patagonian toothfish ranges near the Antarctic Convergence, while the Antarctic toothfish lives further south on the continental shelf and in the Ross Sea.
Are toothfish endangered?
The sources do not provide a specific IUCN status. However, conservation groups have listed them on red lists, and illegal fishing has been a significant concern requiring international regulation.
Good reading and sources
The facts on this page come from the Wikipedia article "Dissostichus", written by its contributors and used under the CC BY-SA 4.0 licence, and from its Wikidata record (CC0). EveryFish rewrote the text in its own words, with AI assistance, and compares every page with the article to make sure no passage is copied. It may be reused under the same CC BY-SA 4.0 licence with a link back.
It may contain mistakes, and figures change over time. Nothing here is investment or buying advice. If something is wrong, tell us. Last refreshed 2026-11-15.
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