Atlantic wolffish lack a swim bladder. This means that they must stay near the bottom, because they are heavier than water and sink as soon as they stop swimming. They are known as a demersal (bottom-dwelling) species.
These are solitary fish, often hiding among rocks or in crevices, where they are protected from predators. The alevins stay in deep water until the vitelline sac (store of food) is resorbed. Afterward, they do not stray far from the spawning grounds. It is possible that the male guards not only the eggs but the alevins as well.
Atlantic wolffish live at temperatures near freezing. To survive the cold, they can synthesize proteins with antifreeze properties – an ability that greatly interests the medical, pharmacology and food industries.
Their skin may be turned into an attractive form of leather used in furniture, clothing and bookbinding.
All wolffish species (spotted, Atlantic, northern and others) are experiencing drastic population declines. Everything points to this disturbing trend being linked to current bottom-fishing techniques. Trawl nets dragged along the bottom are known to destroy the ecosystem of the ocean bottom where they are used.
In fact, all commercially exploitable ocean bottoms have been affected by trawl nets at some point. Wolffish need shelters on the bottom to hide in, and especially to hatch their eggs.