[6] They have prominent canine-like teeth in the front of both jaws; a heavy head with a blunt, rounded snout; small eyes; a long, stout body with no pelvic fins; a long dorsal fin extending to the base of caudal; flexible spiny rays; a small, slightly rounded caudal fin; rounded pectoral fins; firm musculature; colours variable from pale olive to deep brown with upper parts sprinkled with irregularly shaped blackish-brown spots; maximum length to over 1.8 m (5.9 ft) and weight to 23 kg (51 lb).

They prefer a coarse sand and sand/shell hash bottom with rocky areas nearby for shelter and nest-building.

As many as 54,600 large eggs [up to 6 mm (0.24 in) in diameter] are laid in deep water in clusters on the sea floor, and are guarded primarily by males.

[4] Spotted wolffish primarily feed upon hard-shelled invertebrates found on the bottom, such as crustaceans, mollusks and echinoderms.

[1] Overfishing and habitat alteration are believed to have played a role in the observed declines in wolffish abundance.

In Canadian waters, this species is not targeted by the fishing industry, but bycatch mortality by offshore trawlers and long-liners is considered a threat.