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What is a John Dory?

S. Ashraf
S. Ashraf

A John Dory is a type of marine food fish belonging to the family Zeidae. It is a saltwater fish whose natural habitat ranges from mud bottoms along coastal areas to moderately deep waters. John Dory are found in the Mediterranean Sea, the western and eastern Atlantic Ocean as well as along the coasts of the western Pacific Ocean. It is a poor ocean swimmer, so this fish prefers to live close to the sea floor at depths ranging from 15 to 1,200 feet (5 to 360 m).

There are three distinct species of John Dory that are set apart by their location. The American species is Zenopsis ocellata. Zeus faber is the European species, and the Zeus japonicus is found in the Pacific regions.

Veterinarian with a puppy
Veterinarian with a puppy

All species of John Dory share an oval, slender body with a wide mouth, long spines on the dorsal fin and a dark yellow-ringed spot on each side of the body. The species have sharp, microscopic scales that differ in color: the American is silver, and the Pacific and European species are olive green to yellow. A John Dory might grow to be as long as 3 feet (90 cm) and weigh as much as 7 pounds (3 kg). Although it mainly is a solitary fish, it also will form schools.

John Dory fish generally are able to reproduce after they are three or four years old. Spawning takes place toward the end of winter and in the beginning of spring. Fertilization happens when the eggs and sperm are released into the water. In the wild, its lifespan is approximately 12 years.

The John Dory is a predator that feeds on other fish. It first hunts its food by stalking it, then shoots a tube out of its mouth to scoop up the prey. As a predator, it is aided by the dark eye-like spots on each side of its body, which flash and confuse its prey. Also, it has large eyes situated near the top of its head, which give it both depth perception and bifocal vision and help it to locate prey. The John Dory prefers to eat schooling fish such as sardines but also will eat shrimp and squid.

This fish has long been known as an excellent saltwater food fish. Its flesh is firm and white. In 1769, several pickled casks of John Dory were given to Captain James Cook by the Maori on his first voyage to New Zealand.

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    • Veterinarian with a puppy
      Veterinarian with a puppy