Pollack
Pollack, often referred to as Boston bluefish, are fish belonging to the genus Pollachius, part of the Gadidae family. They typically reach a maximum size of 3.5 feet (1 meter) and can weigh up to 35 pounds (16 kilograms), though most are smaller, averaging between 4.5 and 8.75 pounds (2 to 4 kilograms). Characterized by their greenish-brown scales, silver heads, and a distinctive dark green line along their sides, pollack are commonly found in the northeast Atlantic Ocean and southern Baltic Sea, from the Gulf of St. Lawrence down to Virginia along the North American coast.
Pollack are carnivorous, primarily feeding on smaller fish such as young cod, and they often swim in large groups called shoals at depths of 130 to 328 feet (40 to 100 meters), although they can dive deeper. They breathe by taking in water through their mouths, extracting oxygen through gills, which differentiates them from air-breathing animals. During their mating season in winter, females can lay up to 400,000 eggs, which are fertilized by males, a process known as spawning. Pollack generally have a lifespan of around 10 years and are an important species in commercial fishing, similar to cod, haddock, and hake.
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Pollack
Pollack are also known as Boston bluefish. Like many other fish, including cod, haddock, and hake, pollack are caught, sold, and eaten by humans.
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Gadiformes
Family: Gadidae
Genus: Pollachius
Species: Pollachius
Pollack grow to a maximum length of 3 1/2 feet (one meter) and weigh 35 pounds (16 kilograms) but are generally smaller. The average pollack weighs 4 1/2 to 8 3/4 pounds (2 to 4 kilograms) and measures 30 inches (75 centimeters). The pollack has greenish-brown scales on its back, a silver head, and a dark green line along its sides extending from its eye to tail. Their upper body may have dark orange or yellow spots or streaks. Pollacks are similar in appearance to coalfish (Pollachius virens).
Since pollack are fish, and fish need oxygen to breathe, pollack must find oxygen in their watery homes. Unlike humans, pollack do not have lungs to breathe oxygen from the air. Instead, they take in mouthfuls of water and use the oxygen in the water. They release the chemical wastes through the gills on the sides of their bodies.
Pollack inhabit the waters of the northeast Atlantic Ocean and the southern Baltic Sea from the Gulf of St. Lawrence to Virginia along the Atlantic Coast of North America and southward from Greenland to North Carolina. They swim in large groups called shoals. These shoals can swim at depths of 656 feet (200 meters) but usually stay between 130 and 328 feet (40 to 100 meters).
Like other fish, pollack swim using their fins. Their dorsal and anal, or back and belly, fins work together to keep these fish balanced, while their caudal, or tail, fins swish from side to side to propel these fish through the water. Pollack also paddle through the water with their pectoral, or side, fins. All their fins are dark green except their pelvic fins, which are yellowish.
As carnivores, or meat-eating animals, pollack feed on smaller fish, especially small cod. Like other fish, pollack are often preyed upon by larger sea animals. They are also threatened by humans. Like cod, haddock, and hake, pollack are also caught, sold, and eaten by humans.
The mating season for pollack takes place in the winter. A female pollack may lay up to 400,000 free-floating eggs. A male pollack fertilizes these eggs. This process of releasing and fertilizing eggs is known as spawning. Like adult pollack, young pollack travel in large shoals that sometimes include saithe (Pollachius virens). They remain in coastal, rocky areas for 2 to 3 years.
Pollacks have an average life span of about 10 years.
Bibliography
Neeson, Tanya. "Pollachius Virens." Animal Diversity Web, animaldiversity.org/accounts/Pollachius‗virens. Accessed 15 Ap. 2024.
"Pollachius Pollachius." European Commission, Oceans and fisheries, fish-commercial-names.ec.europa.eu/fish-names/species/pollachius-pollachius‗en#ecl-accordion-header-species-descr. Accessed 15 Ap. 2024.
"Pollachius Pollachius (Linnaeus, 1758)." Fish Base, fishbase.mnhn.fr/summary/Pollachius-pollachius. Accessed 15 Ap. 2024.