Common names
Spurdog, Mud shark, Piked dogfish, Whitespotted dogfish, Spotted spiny dogfish, Victorian spotted dogfish, White spotted dogfish, White-spotted dogfish, Whitespotted spurdog, White-spotted spurdog
Spiny dogfish
Squalus acanthias
- Saltwater
- Vulnerable
Max length63 in
Common length39.25 in
Length typeTotal Length
Max weight20 lb 1 oz
Depth range0 - 6488 ft
Max age75 years
Water typeSaltwater
Water temperature45 - 59 °F
Fish info
IUCN Vulnerability status
Short description
Spiny dogfish have slender bodies with an elongated, pointed snout. They feature two dorsal fins with slender spines, no anal fin, and white spots along their bluish-grey back. The underside is pale, and their caudal fin forms a heterocercal tail with asymmetrical lobes. The species name acanthias refers to its defensive spines, located near the dorsal fins. If captured, the shark can arch its back to pierce its predator with these spines, which secrete a mild venom. The second dorsal fin spine is over twice the length of the first, with the first spine starting just behind the rear tips of the pectoral fins. Both the upper and lower jaws have similar blade-like teeth.
Habitat
Typically found inshore in bays, estuaries no deeper than 30m and further offshore in most parts of the world, especially in temperate waters.
Distribution
Western Atlantic Ocean, Indo-Pacific, Mediterranean, and Black Sea. It can be found in both the Northern and Southern Hemispheres, though it is rare in the Atlantic Arctic and absent from the North Pacific.
Behaviour
Spiny dogfish are bottom-dwellers. This shark is known to hunt in packs that can range up into the thousands. They are aggressive hunters and have a sizable diet that can range from squid, fish, crab, jellyfish, sea cucumber, shrimp and other invertebrates. Dogfish sharks experience one of the longest gestation periods of any organism, which can last from around 18 to 24 months.
Edibility
Dogfish fillets taste mild and slightly sweet. The fillets have a dense, flaky, firm texture and turn white when cooked. Dogfish is often used as a cod substitute for fish and chips in the UK.
Lure suggestion
Anglers should try bottom fishing with a traditional sinker-weighted bottom rig. Jigging lures work best when schools of herring, mackerel, or other baitfish are in the area. The best rigs to use for them include the pulley, loop, Carolina, and fishfinder. They are often accidentally caught by anglers who are fishing off of piers. Good bait: clams (best), mackerels, herrings, cut bait, squid and sardines.
Similar species
Other similar species
Pacific spiny dogfish