Like wild dogs on land, spiny dogfish hunt in packs in the sea. These small sharks devour large numbers of herring, salmon, and other valuable commercial fish. They also tear at fishing nets and bite off bait and hooks from fishing lines.
The spiny dogfish serves many useful purposes, however. Many Europeans consider the dogfish good eating. There it is sold frozen, smoked, and salted, and is made into fish-and-chip dinners. The spiny dogfish’s skin is covered with tiny bumps, called "denticles," which give it the feel of fine sandpaper. When dried, the skin can be used to polish wood or as a rough kind of leather. In North America, many high school students know the spiny dogfish from biology class. The shark’s body is often dissected during anatomy lessons. The spiny dogfish has two long spines on its dorsal fins. These spines probably discourage larger fish from biting. The spiny dogfish’s enemies include humans, swordfish, and larger species of shark.
Although not endangered, the spiny dogfish is becoming rare. The species may not be able to recover well from overfishing, because it reproduces slowly. Adult females give birth only once every two years. The newborns are often eaten by larger fish. Young dogfish also mature very slowly, and do not have babies of their own until they are six to 20 years old.
class: Sharks and rays
order: Dogfish sharks
family: Dogfish sharks
length: 28 to 40 inches
diet: small fish, squid, shrimp, sea anemones, jellyfish, and algae
number of young: 6
home: oceans worldwide
- Deep-sea Swallower
- Deep-sea Viperfish