Patagonian Toothfish (S/F)

Patagonian toothfish (illustration from SeafoodSource)

The Patagonian toothfish (Dissostichus eleginoides) is a type of cod icefish that is found in the cold, temperate waters of the Southern Hemisphere, though in the Southern Ocean. It is only found on seamounts and continental shelves around sub-Antarctic islands. In the fishing industry and market, it is more commonly known as the Chilean sea bass, which supposedly originated as a marketing gimmick to make the fish sound more palatable.

Description

Commercially caught toothfish average at 9-10 kg (20-22 lbs), though large adults can occasionally weigh about 200 kg (440 lbs) and can reach lengths of up to 2.3 m (7.5 ft). Because of their deep-water habitat, they are not extremely colorful and are usually dark brown or gray. The eyes and mouth are large, and the body is roughly bullet-shaped and narrow.

It has large pectoral fins but small pelvic fins. The dorsal and anal fins are very short; it has two dorsal fins, one directly opposite the pelvic fins and one extending from just past the midway point of the fish’s back all the way to its caudal peduncle. Its anal fin is shorter in height than the second dorsal fin, but extends about as far down the body. The caudal fin, or tail fin, is moderately-sized and slightly forked.

Growth

The Patagonian toothfish begins its life as a free-floating egg which hatches into a planktonic larva. It spends its early life in shallower water for about six or seven years, after which point it is closer to the appearance of a mature fish and begins migrating into deeper water.

They are thought to live for up to fifty years.

Sexual Dimorphism

Currently, there is no known sexual dimorphism in this fish.

Habitat
Preferred Habitat

The Patagonian toothfish lives in cold, deep oceanic waters, from 300 – 3,500 m (984 – 11,483 ft) around most sub-Antarctic islands as well as around the Prince Edward Islands of South Africa, and Heard Island and McDonald Island in Australia. Juveniles start out their lives in shallow water (less than 300 meters deep) and remain in the demersal zone, near the seafloor. As they age, they migrate deeper. They are generally found near seamounts and continental shelves.

Isla Nublar

While the Chilean sea bass was imported to Isla Nublar as a food item to be served in restaurants, it is unlikely that any were kept alive on-site at Jurassic Park or later in Jurassic World.

Isla Sorna

It is not known if the Chilean sea bass was ever imported to Isla Sorna as food. As no tourist facilities existed on this island, it is unlikely.

Other

This fish lives naturally in the southern Atlantic, Pacific, and Indian Oceans. It is also found widely throughout the Southern Ocean.

Behavior and Ecology
Activity Patterns

Living in deep, cold waters, the Patagonian toothfish is mostly unaffected by light cycles. Like most fish, it does not truly sleep.

Diet and Feeding Behavior

Juveniles living in shallow waters are primarily piscivorous, feeding on smaller fish. As the animal ages, it migrates into deeper parts of the ocean and begins to take other food sources as well, such as small squid and crustaceans such as prawns. They are also known to scavenge dead animals. It feeds by biting down on a food item and swallowing it whole, as it cannot chew. It may break off pieces of a food item if it cannot eat it all at once.

Social Behavior

Though it may school with its own kind, little is known about its social life.

Reproduction

Patagonian toothfish spawn in the Southern Hemisphere’s winter months, typically at depths of around one thousand meters. The eggs and larvae are planktonic, and once they can swim, they will settle in the demersal zone of shallower water to mature.

Communication

It is unable to vocalize, like the majority of fish. Other details about its communication methods are poorly understood at this time.

Ecological Interactions

The Patagonian toothfish makes up a large part of the diets of large predatory species in its habitat, including sperm whales, southern elephant seals, and colossal squid. It feeds on smaller fish and squid, as well as pelagic crustaceans.

Cultural Significance
Symbolism

Patagonian toothfish are a good example of a species having a market name different from its common name. It and the Antarctic toothfish are marketed as Chilean sea bass, a name which makes them sound fancier and more palatable to seafood diners. This increases sales and allows the fish to be sold at a higher price.

In Captivity

At the moment no efforts have been made to mariculture the Patagonian toothfish.

Science

While it is not extremely well-studied, the Patagonian toothfish provides useful information about the ecology of the Southern Ocean and south regions of the Pacific, Atlantic, and Indian Oceans. Because the Southern Ocean is a major source of fish for fisheries, information about the region’s ecology is extremely valuable. Toothfish such as this species are one of the Southern Ocean’s major exportable resources. The Commission for the Conservation of Antarctic Marine Living Resources currently studies the relationships the Patagonian toothfish has with other species in its environment to determine how best to harvest them for food.

Because it is higher up the food chain, it can suffer from bioaccumulation of mercury. This means it can be used to determine how much mercury pollution is in the area.

Politics

The Patagonian toothfish is considered a fish to avoid by the Monterey Bay Aquarium’s Seafood Watch due to overfishing and high levels of mercury. Fisheries that were ranked safest and most ethical to buy from were the Heard and McDonald Islands, Macquarie Island, and Falkland Islands fisheries, with the Kerguelen Islands, South Georgia, and Ross Sea fisheries being good alternatives. The Prince Edward and Marion Islands, Chilean, and Crozet Islands fisheries were listed as ones to avoid. Argentinian fisheries were not reviewed.

In 2010, Greenpeace International added the toothfish to its seafood red list because the fish which were commonly sold in supermarkets had been acquired illegally.

Toothfish fisheries are managed by the Commission for the Conservation of Antarctic Marine Living Resources, which treats the whole of the Southern Ocean as a living system when considering fishery management policy. One of the major focuses of the CCAMLR is bird exclusion, ensuring that seabirds do not become entangled with the fishing lines or otherwise harmed. Birds are a major part of the marine ecosystem and contribute to its overall health; without them the ocean would become less productive, harming fisheries in the long run.

Resources

This fish is commonly targeted for food by humans and is sold in countries including Chile, the United States, Argentina, Peru, Uruguay, France, Spain, Britain, Korea, and Japan. In the past, France sold some of its fishing rights to foreign fisheries, particularly to the Japanese. Overfishing has drastically impacted this species, leading to restrictions on where it may be fished and how much can be taken.

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Chilean sea bass

In cuisine, the fish is typically frozen at sea and then re-frozen for the market. Its fillets are shiny and resilient, with a white color and rich flavor. The meat is tender and moderately oily, coming apart in thick strips or flakes when eaten. Chilean sea bass is considered excellent for grilling, but can also be broiled, sautéed, or smoked, but is not suitable for frying because of its oil content.

InGen has historically imported Chilean sea bass to their Isla Nublar facilities to serve guests. This was notably the only meal served to actual guests of the original Jurassic Park, due to the 1993 incident closing down operations on the island during the endorsement tour. Chilean sea bass was also imported to Jurassic World, where it was served in Winston’s Steakhouse.

Safety

You will probably not encounter a live Patagonian toothfish in the wild because they live in deep, remote parts of the ocean, but you may find them as food in restaurants. Certain fisheries obtain this species illegally, and it may be contaminated with harmful levels of mercury. Eat with discretion.