St. Lawrence species

Witch flounder

Glyptocephalus cynoglossus

Type of resource

  • Bottom fish
  • Fish

Status of the resource

  • Vulnérable

In season

Fresh from May to October.

SIZE : Up to 78 cm for 5 kg.

LIFE EXPECTANCY : Up to 30 years.

LIFE CYCLE : Late sexual maturity.

Spawning generally takes place between March and September. The transparent, spherical eggs float with the currents. Incubation takes approximately 7 or 8 days. The larvae can remain in the water column for up to a year. When the small fish reach a size of 40 mm to 50 mm, the location change of the eyes occurs.

Fish becoming smaller and smaller

Over-fishing can alter the size and maturation age of fish. Before intensive fishing in the Gulf of St. Lawrence, female witch flounder reached maturity at between 40 cm and 45 cm and males at between 30 cm and 34 cm. In the 2000s, the adult stage of the fish began at smaller sizes: around 28 cm for females and 26 cm for males.

Witch flounder is a flatfish with a small head and mouth. Its body is oval, long and very compact, with a straight lateral line. The side with the eyes is dark greyish-brown, and its blind side is grayish-white. Its fins have dark edges. Mucus pores are visible on the side with no eyes.

On the bottom, between 45 m and 400 m in depth, but can go down to 1600 m.

The witch flounder favors cold water, between 2 °C and 6 °C, and sandy, clay, or muddy bottoms.


Small crusta-ceans
Marine worms
Molluscs bivalves



MACHINES : Seine, trawl.


  • Quotas
  • Fishing season
  • Minimum catch size of 30 cm

The witch flounder biomass has suffered a decline in the 1990s. Quotas have been lowered, and the biomass has been showing signs of recovery since the 2010s. However, because of their low fecundity, slow growth and late maturation, the witch flounder remains vulnerable.

Good news. They are less susceptible to being preyed upon by gray seals because they live farther in depth than other type of flounder.

Careful monitoring remains necessary to ensure its conservation.

Low in fat and rich in vitamin B12 and in selenium.

Delicate, flaky texture. Witch flounder gives fine, long fillets, and its delicate white flesh is highly appreciated. All cooking methods are suitable.


  • The witch flounder’s flavor can be a little bland. It is best to season the fish generously.
  • Delicious when pan-fried or breaded, cooked in butter and served with a squeeze of lemon.

Change of identity

Fish rebranding involves the renaming of species to make them more appealing for consumers. For example, in England, witch flounder, normally known as witch, is sometimes called “Torbay sole” to make it more familiar and similar to the common sole and (Solea solea), also known as the Dover sole. This process is designed to encourage the purchase of lesser-known fish.