Spiny dogfish

Spiny dogfish (Squalus acanthias)

The spiny dogfish has dorsal spines, no anal fin, and white spots along its back. Males mature at around 11 years of age, growing to 80-100 cm in length; females mature in 18-21 years and are slightly larger than males, reaching 100-124 cm. The species name acanthias refers to the shark's two spines. These are used defensively; if captured, the shark can arch its back to pierce its captor. Glands at the base of the spines secrete a mild poison.The spiny dogfish forms large schools of hundreds to thousands of sharks. It is from this behavior that their name is derived, as fisherman likened these large schools to packs of dogs. Schools are often composed entirely of sharks of like size and sex. The shark feeds on bony fishes, smaller sharks, and various invertebrates. It is also a common prey item for large fish, other sharks, and marine mammals.

Spiny dogfish distribution