Lumpfish

The Lumpfish (Cyclopterus lumpus) — also called the lumpsucker — is a globular, scaleless fish and the only species in its genus, found throughout the cold waters of the North Atlantic from North America to Europe and the Arctic. Its most notable feature is the ventral suction disc formed from fused pelvic fins, which allows it to anchor firmly to rocks and other surfaces. Lumpfish undertake a seasonal shift from an offshore pelagic life to shallow rocky shores during the breeding season. In recent decades the species has also gained attention for its use as a natural cleaner fish in salmon aquaculture. It is not currently considered globally threatened.

Look for these features to identify a Lumpfish:

• Rounded, globe-like or tadpole-shaped body outline
• Thick, rubbery, scaleless skin with rows of bony tubercles along the back and sides
• Blue-grey, olive, or reddish-brown coloration, often duller and smaller in males
• A large ventral sucking disc formed from fused pelvic fins
• Small dorsal and anal fins positioned far back near the tail
• Marked size difference between sexes, with females larger and rounder

No other North Atlantic fish shares its unmistakable rounded body and sucker disc combination.

Lumpfish range across the cold waters of the North Atlantic, from the northeastern coast of North America and Greenland to Iceland, Scandinavia, the British Isles, and into the Barents Sea. For most of the year, adults live a pelagic existence in open, cold water, sometimes associating with drifting seaweed rafts far from shore. During the breeding season they migrate into shallow, rocky intertidal and subtidal zones to spawn, after which adults typically return to deeper offshore water. Depth range spans from the shoreline to several hundred meters, and the species is well adapted to cold, subarctic temperatures.

Lumpfish are slow-moving and largely solitary, depending on camouflage and their tough, tubercle-studded skin rather than speed for protection from predators. The ventral sucker disc lets them anchor to rocks, kelp holdfasts, or other hard surfaces, conserving energy in areas with strong currents or surge. During the breeding season, females lay large masses of eggs on rocky substrate in shallow water, and males remain to guard, fan, and protect the eggs until they hatch, showing an unusually high level of paternal care for a fish. Outside breeding, Lumpfish feed on small crustaceans, jellyfish, ctenophores, and other soft-bodied invertebrates drifting in open water.