The Atlantic Wolffish…a Species at Risk in the North

This species has been identified as Special Concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). It is listed under the federal Species at Risk Act (SARA) and was afforded protection under the SARA as of June 2004. Additional protection is afforded through the federal Fisheries Act. Under the SARA, a management plan must be developed for this species.

General Description

Anarhichas lupus

Photo Credit: Andrew J. Martinez

Atlantic Wolffish (Anarhichas lupus) are large marine fishes from the Anarhichadidae family. Other common names include Catfish, Striped Wolffish and Ocean Wolffish. They have the following characteristics:

• Prominent canine-like teeth in the front of both jaws;
• Heavy head with a blunt, rounded snout and small eyes;
• Long, stout body with no pelvic fins;
• Dorsal fin long and extending to base of caudal, with flexible spiny rays;
• Caudal fin small and slightly rounded, pectoral fins heavy and rounded;
• Firm musculature;
• Colour is variable from slate blue to dull olive green to purplish brown, usually with 10 or more dark vertical bars, irregular and broken;
• Underside of head and belly are dirty white, tinged with upper body colour; and
• Size is variable but can reach 1.5 m in length and over 24 kg in weight.

Distribution

In the Arctic, the Altantic Wolffish occurs in the Davis Strait, the northernmost limit of its distribution. In addition, it is widely distributed across the North Atlantic Ocean from southern Newfoundland to the Barents Sea. In the western North Atlantic, it occurs off west Greenland and southern Labrador and in the Strait of Belle Isle. It is also common on the Scotian Shelf and in the Gulf of Maine and Bay of Fundy.

Atlantic Wolffish Distribution in Arctic Canada

Permission provided by B.W. Coad (CMN) and J.D. Reist (DFO); prepared by N. Alfonso (CMN).

Habitat and Life History

The Atlantic Wolffish is usually found between 50 and 150 m in depth and 0.4º and 6.0ºC over rocky and sand bottoms. Maturity is attained between 5 and 11 years of age. In eastern Newfoundland waters, it spawns in September/October. Up to 37,290 large eggs (6.5 mm in diameter) are deposited in a mass in crevices where they are guarded by the males until they hatch. Males have also been noted to aerate and turn the mass of eggs. Larvae are pelagic and remain on or close to the bottom for the entire larval stage. The Atlantic Wolffish is a solitary species and large schools are not observed. Short, seasonal inshore movements may occur in the spring where mature fish are found at depths of 0 to 150 m. Specimens aged at over 20 years have been captured off Iceland.

Diet

The diet of the Atlantic Wolffish consists primarily of bottom invertebrates, including echinoderms, molluscs, crustaceans and small amounts of fish.

Threats

There are no direct studies of factors responsible for the declines observed in wolffish abundance but it is believed that overfishing and habitat alteration have played a role. This fish species is not targeted by the fishing industry, however, by-catch mortality by offshore trawlers and long-liners is considered a threat. In addition, activities which disturb the ocean bottom, such as trawling, may damage spawning habitat.

Similar Species

The Atlantic Wolffish can be distinguished from the Northern Wolffish (A. denticulatus) and the Spotted Wolffish (A. minor) by its vertical stripes.

Text Sources: Scott and Scott 1988; COSEWIC Status Report 2000; Stock Status Report 2004/031 2003.

For more information, visit the SARA Registry Website at www.SARAregistry.gc.ca.