Brill

Brill (Scophthalmus rhombus) is a left-eyed flatfish in the family Scophthalmidae, closely related to turbot but generally less well known despite occupying similar habitats. It has a more elongated, oval body and smooth scaled skin, distinguishing it from the rounder, tubercle-skinned turbot. Brill are found along the coasts of Europe, from Scandinavia and the North Sea south through the English Channel and Bay of Biscay to the Mediterranean and Black Sea. The species supports modest commercial fisheries across parts of its range and is not currently considered threatened, though it is less abundant than some of its flatfish relatives.

Brill can be distinguished from the closely related turbot and other European flatfish by several features.

• Body: elongated oval, more slender and less rounded than turbot
• Eyes: both on the left side
• Skin: smooth, covered in small scales rather than turbot's bony tubercles
• Coloration: mottled sandy brown to grayish-brown upper side with faint pale spotting, plain white underside
• Size: typically 40-60 cm Its smoother, scaled skin and more elongated profile are the clearest ways to separate brill from turbot, which has a broader, rounder body and rough tubercle-studded skin.

Brill live on sandy and muddy seabeds of coastal and continental shelf waters, typically at depths from shallow nearshore zones down to around 100 m. Their range extends along the eastern Atlantic from southern Scandinavia and the North Sea through the English Channel, Irish Sea, and Bay of Biscay to the Mediterranean and Black Sea. They favor similar habitat to turbot but are generally found in somewhat deeper or more open sandy areas. Brill tolerate a range of temperate water conditions and are primarily a fully marine species, though they may occasionally be found in slightly brackish coastal waters.

Brill are solitary, bottom-dwelling ambush predators, lying camouflaged against sandy or muddy substrates to surprise passing fish and crustaceans. Like their relative the turbot, they rely on cryptic coloration and partial burial in sediment for both hunting and predator avoidance. They are not schooling fish and generally remain within a home range on suitable seabed habitat, with movement driven mainly by prey availability and spawning migrations. Spawning occurs in spring and summer in coastal and shelf waters, with females releasing numerous small pelagic eggs that drift with ocean currents before larvae settle to the bottom and transform into juvenile flatfish. Brill contribute to coastal food webs as both predator and prey.