Black Sea Bream

Black Sea Bream, Spondyliosoma cantharus, is a deep-bodied member of the porgy family (Sparidae) found in the Eastern Atlantic from Norway and the British Isles south to South Africa, as well as throughout the Mediterranean Sea. It is not currently considered at risk. Despite its common name, adult coloration is more silvery-grey to bronze than truly black, with the darker appearance most pronounced in breeding males. The species is notable for its nest-guarding reproductive behavior, unusual among sparids, in which males construct and defend depressions on the seabed. It typically associates with rocky reefs, wrecks, and adjacent sandy or weedy bottoms, making it a familiar sight on temperate reef systems across its wide latitudinal range.

Key features:

• Deep, oval, laterally compressed body
• Silvery-grey to bronze coloration, with faint dark vertical bars more pronounced in breeding males
• Single, continuous dorsal fin with stiff spines
• Small, terminal mouth with fine teeth
• Forked tail fin

Adults typically measure 20-35 cm. Breeding males darken noticeably and develop a more pronounced blackish hue, which is the likely origin of the common name. The species can be distinguished from Gilthead Bream by the absence of the golden forehead band and from Silver Bream by its much deeper, more oval body shape and marine rather than freshwater habitat.

Black Sea Bream ranges throughout the Mediterranean Sea and the Eastern Atlantic from Norway and the British Isles south to South Africa. It favors rocky reefs, wrecks, and areas of mixed sand and weed from shallow inshore water down to about 300 m, though it is most commonly encountered between 15 and 50 m. The species shows a marked seasonal inshore migration, moving into shallower coastal waters during spring and summer to breed before retreating to deeper offshore habitat in winter. Juveniles often use shallower, more sheltered rocky and weedy habitats than adults, gradually shifting to deeper reef structure as they mature.

Black Sea Bream displays an unusual reproductive behavior for a sparid: breeding males excavate and guard circular nest depressions on sandy or gravelly seabed, defending them against intruders and courting females to spawn within. After spawning, males typically continue guarding the eggs until they hatch. Outside the breeding season, the species is loosely social, often forming small to moderate groups over rocky and mixed-bottom habitat. It feeds opportunistically on a mix of small invertebrates, including worms, crustaceans, and mollusks, along with some algal material. Seasonal inshore spawning migrations concentrate breeding males in shallow nesting areas, a period when the species is most conspicuous and easily observed by divers.