Heterodontus francisciHorn shark

Geographic Range

Heterodontus francisci lives in warm-temperate and subtropical regions of the eastern Pacific. It is mainly found inhabiting the coastal areas from Southern California to the Gulf of California and also areas around Ecuador and Peru (Compagno 1984).

Habitat

Horn sharks live in temperate waters in the Eastern Pacific. They dwell along the water bottom frequently in kelp beds laying 8-12 meters deep. Horn Sharks have been found in caves as deep as 200 meters, but usually they remain at much shallower depths (Castro 1983).

Physical Description

The horn shark gets its name because it has a short, blunt head with high ridges above the eyes (Castro 1983). Heterodontus francisci range in size from approximately 97cm to 120cm (Compagno 1984). They are a brownish color covered in black spots and their underbellies have a yellowish tint (Compagno 1984; Castro 1983).

  • Range mass
    0 to 0 kg
    0.00 to 0.00 lb
  • Average mass
    10 kg
    22.03 lb

Reproduction

Horn sharks mate in the months of December and January. "The male horn shark chases the female until the latter is ready, then both drop to the (ocean) bottom. The male grabs the female's pectoral fin with his teeth and inserts a single clasper in her cloaca; copulation lasts 30 to 40 minutes" (Compagno 1984). A few weeks after copulation, the female will deposit the fertilized eggs amongst the rocks where they will hatch anywhere from 6-9 months later. The young sharks, when first born, will be roughly 15-17cm in length (Castro 1983; Compagno 1984; Stevens 1987).

Lifespan/Longevity

  • Average lifespan
    Status: captivity
    12 years
    AnAge

Behavior

Horn sharks are very inactive creatures. They don't spend a lot of time swimming rapidly through the waters. They are sluggish and spend their days in the rocks. During daylight hours they are usually found with their heads hidden in a crevice. They are nocturnal animals and at night they come out to feed (Castro 1983; Compagno 1984; Stevens 1987).

Heterodontus francisci is not an aggressive creature. It poses virtually no threat to humans because it would rather swim away from a diver than try and attack a much larger creature which might be a predator (Stevens 1987).

Food Habits

The diet of horn sharks consists mainly of small fishes and invertebrates. Heterodontus francisci have been known to eat many types of small fish; however, their chief staples are mollusks, sea urchins, and crustaceans. Since horn sharks are fairly inactive they prefer to wait for their prey to swim by before attacking it and feasting. But they won't necessarily lie still waiting for food to come by (Compagno 1984; Castro 1983; Stevens 1987).

Economic Importance for Humans: Positive

The horn shark does not have a great deal of commercial value. Some people catch them "for sport and for its large fin spines, which are made into jewelry" (Compagno 1994, p. 157). However the most important value of Heterodontus francisci comes from research. These sharks have been known to survive in captivity for as many as twelve years where scientists study them (Castro 1983). This is important because most sharks die shortly after they are placed into captivity; usually because they stop eating. Therefore, the horn shark proves quite valuable to scientists wishing to study sharks (Compagno 1984; Castro 1983; Stevens 1987).

Economic Importance for Humans: Negative

Horn sharks do not have any negative effect on humans. They will not even attack humans, prefering to flee if a person comes near (Stevens 1987).

Conservation Status

Horn sharks are not an endangered species. Therefore, they have no special status. They have been known to vacate certain areas with a high number of divers. But as long as divers don't drastically increase all along the Eastern Pacific Coast horn sharks should remain off the endangered species list.

Contributors

William Fink (editor), University of Michigan-Ann Arbor.

Matt Herstein (author), University of Michigan-Ann Arbor.

Glossary

Pacific Ocean

body of water between the southern ocean (above 60 degrees south latitude), Australia, Asia, and the western hemisphere. This is the world's largest ocean, covering about 28% of the world's surface.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

coastal

the nearshore aquatic habitats near a coast, or shoreline.

motile

having the capacity to move from one place to another.

natatorial

specialized for swimming

native range

the area in which the animal is naturally found, the region in which it is endemic.

References

Castro, J. 1983. The Sharks of North American Waters. Texas A&M University: Texas A&M University Press.

Compagno, L. 1984. Sharks of the World. Rome: United Nations Developement Programme.

Stevens, J., L. Compagno, C. Creagh, G. Dingerkus, H. Edwards. 1987. Sharks. London: Merehurst Press.