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Alaska pollock

life science Maturity 5-7

The Alaska pollock is a fish.

Theragra finnmarchica.jpg
Theragra finnmarchica.jpg
It lives in the cold ocean. It likes to swim in big groups. Many people eat this fish for food. It can even make fake crab meat!
Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG
Do you like to eat fish?

45 words

The Alaska pollock is a fish.

Theragra finnmarchica.jpg
Theragra finnmarchica.jpg
It lives in the cold North Pacific ocean. It likes to swim in big groups. This fish has spots on its skin. These spots help it hide on the sandy ocean floor.
Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG
Storms in the summer can help more baby fish live. The storms stir up food in the water. People eat this fish in many ways. It is used to make fake crab meat. It is also used in fish sandwiches.
Alaska pollock roe Russia.jpg
Alaska pollock roe Russia.jpg
This fish is very important to the ocean.

96 words

The Alaska pollock is a very important fish.

Theragra finnmarchica.jpg
Theragra finnmarchica.jpg
It lives in the cold North Pacific ocean. Most of these fish live in the Bering Sea. They like to swim in large groups called schools. Their skin has spots on it. These spots help them hide on sandy ocean floors.
Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG

Stormy summers can help these fish grow. Storms stir up nutrients in the water. This helps tiny plants called phytoplankton grow. More food means more baby fish survive.

Pollock also move up and down in the water. They follow their food to stay full. In August, they swim near the surface. In November, they swim much deeper.

People catch a lot of this fish for food. It is used to make surimi. Surimi is a material used for imitation crab meat.

Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG
It is also used in many fast food fish sandwiches. In some places, people eat the roe. Roe are the tiny eggs of the fish.
Alaska pollock roe Russia.jpg
Alaska pollock roe Russia.jpg
In Korea, this fish is even called the national fish.

179 words

The Alaska pollock is a very important marine fish. It lives in the cold North Pacific Ocean. Most of these fish live in the eastern Bering Sea. They swim together in large groups called schools. These fish are part of the cod family. They have speckled skin to help them hide. This coloring makes it hard for predators to see them near sandy floors.

Theragra finnmarchica.jpg
Theragra finnmarchica.jpg

These fish follow a special way of moving in the water. This is called diel vertical migration. They move up and down to follow their food. In August, they swim near the ocean surface. This happens because food is plentiful there. In November, they swim much deeper. They do this to stay with their planktonic food source.

Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG

Scientists have spent many years studying this fish. In 1956, a zoologist named Einar Koefoed found a fish in Norway. He thought it was a new species called the Norway pollock. Later, researchers used DNA to study the fish. They found that the Norway pollock is the same as the Alaska pollock. The official scientific name is Gadus chalcogrammus. This name was confirmed by the U.S. Food and Drug Administration in 2014.

Theragra finnmarchica.jpg
Theragra finnmarchica.jpg

Alaska pollock is a huge part of the ocean's food web. Stormy summers can actually help more fish survive. Storms stir up nutrients in the water. This helps tiny plants called phytoplankton grow. More plants mean more food for baby pollock. The fish also have drumming muscles. They use these muscles to make sounds during courtship.

Alaska pollock roe Russia.jpg
Alaska pollock roe Russia.jpg

Many people around the world eat this fish. It is the second most caught fish species in the world. In the United States, it is used for many fast food sandwiches. It is also the main material for surimi. Surimi is used to make imitation crab meat.

Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG
In Korea, it is known as the national fish. People there even dry it in the winter. In Russia, people enjoy the roe as a spread.
Alaska pollock roe Russia.jpg
Alaska pollock roe Russia.jpg

344 words

The Alaska pollock, scientifically known as Gadus chalcogrammus, is a highly significant marine fish species. It belongs to the cod genus, Gadus, and the family Gadidae. These fish are semi-pelagic, meaning they live in the water column rather than staying strictly on the ocean floor. They are schooling fish, which means they travel together in large, organized groups. The Alaska pollock is widely distributed across the North Pacific Ocean. The largest concentrations of these fish are located in the eastern Bering Sea.

Understanding the biological classification of the Alaska pollock has required significant scientific research. In 1956, the species was placed in its own genus, Theragra, and named Theragra chalcogramma. However, research conducted in 2008 revealed a close genetic relationship to the Atlantic cod. This discovery suggested the fish should return to the Gadus genus. In 2014, the U.S. Food and Drug Administration officially changed the name back to Gadus chalcogrammus. Major scientific registries, such as the World Registry of Marine Species, have since adopted this name. While common names like "walleye pollock" are still used in trade, scientists consider them somewhat misleading.

Theragra finnmarchica.jpg
Theragra finnmarchica.jpg

The ecology of the Alaska pollock is deeply connected to the health of the Bering Sea. These fish have speckled coloring, which provides camouflage against sandy ocean floors. This helps them avoid being seen by predators. The species is relatively fast-growing and has a short lifespan. Interestingly, the population size is affected by weather patterns. When stormy summers occur, they stir up nutrients in the water. These nutrients promote the growth of phytoplankton, which is a tiny plant-like organism. A higher amount of phytoplankton leads to better survival rates for pollock hatchlings.

Hwangtae (Gadus chalcogrammus).jpg
Hwangtae (Gadus chalcogrammus).jpg

Pollock foraging behavior changes significantly based on the age of the fish. Young pollock are divided into two groups based on their length. Fish smaller than 60mm mainly eat copepods, which are tiny crustaceans. Those larger than 60mm eat copepods but also forage for krill. This difference means that a lack of food affects smaller fish more heavily. Seasonality also plays a role in how they hunt. During winter, food is scarce and hunting is risky due to predators. Large young pollock can store more energy and do not need to hunt as much in winter. Smaller fish lack this storage capacity and must continue foraging, increasing their danger.

Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG

These fish also participate in diel vertical migration to find food. This is a process where fish move up and down in the water column. While they move vertically during the day, their average depth changes with the seasons. This movement is not driven by light or temperature, but by the movement of their food. In August, food is abundant near the surface, so pollock stay in shallower depths. In November, they move to deeper waters to follow their planktonic food source.

Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG

History shows a complex relationship between the Alaska pollock and the Norwegian pollock. In 1956, zoologist Einar Koefoed identified a rare fish in Norway as a separate species, Theragra finnmarchica. He based this on morphological differences, or physical appearances, from specimens caught in 1932. However, modern genetic analysis has changed this view. DNA sequencing of specimens showed no significant genetic differences between the two. Researchers concluded that the Norway pollock is actually the same species as the Alaska pollock. This makes the Norway pollock a junior synonym of Gadus chalcogrammus.

Theragra finnmarchica.jpg
Theragra finnmarchica.jpg

The Alaska pollock is a massive component of the global fishing industry. It is the second most important fish species in the world by total catch. In the United States, pollock landings are the largest of any single fish species. Between 1979 and 2022, the average annual catch in the eastern Bering Sea was 1.26 million metric tons. U.S. fisheries maintain a consistent average of about 1.3 million tons per year. Most of this, about 92 percent, comes from the Bering Sea. To prevent overfishing, the Alaska Fisheries Science Center conducts stock assessments to set yearly quotas.

This fish is a primary ingredient in many different food products. It has a mild taste, white color, and low oil content compared to other cod. High-quality fillets are often used for breaded fish products in Europe and North America. The fish is also the main material for surimi, which is used to make imitation crabmeat. Surimi can be found in many forms, such as chunks, legs, flakes, salads, or shreds. In Korea, the Alaska pollock is considered the national fish. In Russia, the roe, or fish eggs, is often sold as a canned spread.

Alaska pollock roe Russia.jpg
Alaska pollock roe Russia.jpg

771 words
🖼️ Images & Media (5)
File:Theragra finnmarchica.jpg
Theragra finnmarchica.jpg
File:Alaska pollock(=walleye poll.), capture production, million tonnes, 1950-2022.svg
Alaska pollock(=walleye poll.), capture...
File:Japanese Sugiyo Kanikama Kaoribako2.JPG
Japanese Sugiyo Kanikama Kaoribako2.JPG
File:Alaska pollock roe Russia.jpg
Alaska pollock roe Russia.jpg
File:Hwangtae (Gadus chalcogrammus).jpg
Hwangtae (Gadus chalcogrammus).jpg
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