LAST UPDATED: 01.07.2023
LAST UPDATED: 01.07.2023
SPINY DOGFISH
SPINY DOGFISH
Squalus acanthias
Squalus acanthias
The spiny dogfish (Squalus acanthias) is a coastal squaloid shark with a circumboreal distribution. In addition to being the most abundant shark in the western North Atlantic, it is also one of the most highly migratory species¹. Dogfish range from Labrador to Florida, but are most abundant from Nova Scotia to Cape Hatteras, North Carolina². The spiny dogfish travels in schools of hundreds or thousands of individuals.
The spiny dogfish is slow to mature and is thus vulnerable to overfishing. It has one of the longest gestation periods of any vertebrate animal, produces small litters of pups, and is slow growing.
In spite of its precarious situation, it remains one of the most abundant shark species in the world.
¹ Bigelow, H.B. and W.C. Schroeder. 1953. Fishes of the Gulf of Maine. U. S. Fish Wildl. Serv., Fish. Bull. 53. 577 p.
² Rago, J.P., K. Sosebee, J. Brodziak, and E.D. Anderson. 1994. Distribution and dynamics of northwest Atlantic spiny dogfish (Squalus acanthias). Northeast Fish. Sci. Cent. Ref. Doc. 94-19.
Order – Squaliformes
Family – Squalidae
Genus – Squalus
Species – S. acanthias
NAMES
NAMES
Scientific name: Squalus acanthias
Common names: Spiny dogfish, mud shark, piked dogfish, spurdog.
Mi’kmaw names: Se ku lah-te, sĭgŭlăde-ek, sikɨlati, wibi’damok, wipitamekw.
French common names: Aiguillat commun, chien de mer.
GENERAL DESCRIPTION
GENERAL DESCRIPTION
• Average length of 0.75 to 1.05 meters.
• Grey or brownish upperparts and pale grey or white ventral side.
• Irregular white spots on the back and flanks.
• Long, sharp spines in front of the dorsal fins.
• Asymmetrical caudal fin (tail) with larger top lobe.
• Lacks anal fin.
• Most common shark in the world, often swimming in schools numbering in the hundreds.
• Seasonal presence in Atlantic Canada and Quebec, including the St. Lawrence Estuary.
• Rare winter captures in the Saguenay Fjord.
DISTRIBUTION
DISTRIBUTION
The spiny dogfish is found throughout the entire Gulf of St. Lawrence and into the Estuary and Saguenay Fjord. The porbeagle arrives in the St. Lawrence in early summer and has mostly departed by winter. There are two outlier cases of spiny dogfish caught by ice-fishers in the Saguenay Fjord in January and February. The duration of its annual migration to the St. Lawrence may be affected by warmer conditions resulting from climate change.
(BELOW) Provisional distribution of the spiny dogfish, Squalus acanthias, in the St. Lawrence and Atlantic Canada, based on research by the St. Lawrence Shark Observatory. Only historical and select cases are posted to illustrate overall range. This map is updated with new and historical data on an ongoing basis. Map does not include data from the U.S. except borderline cases. To submit additional sightings or captures, please contact us. Click on icons for observation details.
FISHERIES
FISHERIES
The spiny dogfish is the target of a directed fishery in Atlantic Canada, however landings are considered minimal.
CONSERVATION STATUS
CONSERVATION STATUS
The spiny dogfish is listed as an special concern species by COSEWIC (Committee on the Status of Endangered Wildlife in Canada).
Jeffrey Hay Gallant, MSc, is the founder and Scientific Director of the St. Lawrence Shark Observatory (ORS) and a doctoral researcher at UQAM. He made his first shark observation at Peggy’s Cove in 1975, first shark dive off Chebucto Head in 1992, co-led the first Canadian cage dives off Halifax in 2000, and was the first person to film a free-swimming Greenland shark in 2003.