Cetorhinus maximusbasking shark(Also: Bone shark)

Geographic Range

North and South Atlantic and Pacific Oceans.

Habitat

Basking sharks inhabit subpolar and temperate seas moving southward during the winter. They prefer surface waters of the open sea, straying inland only to breed in the summer.

Physical Description

The basking shark has a conical snout, enormous gills, dark bristle-like gill rakers, and a crescent-shaped tail. Teeth are small and numerous(about one hundred per row) with a single conical cusp usually curved backwards, and similar in both jaws. Color is grayish brown to black above, often with blotches of a lighter color, and pale with blotches on the belly. Average size of this shark ranges from 7-9 m.

  • Average mass
    3900 kg
    8590.31 lb
  • Average mass
    2.2e+06 g
    77533.04 oz
    AnAge

Reproduction

Basking sharks are believed to be ovoviviperous. Females mature at 4-5m. Embryos supposedly measure between 1.5-1.8m in length.

  • Average age at sexual or reproductive maturity (female)
    Sex: female
    4197 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    2920 days
    AnAge

Lifespan/Longevity

  • Average lifespan
    Status: captivity
    32 years
    AnAge

Behavior

This is a migratory speciesal though its seasonal movements aren't well known. They dwell in northern waters as long as the plankton population is abundant, moving south in the winter. Though they are largely oceanic sharks, they can be found off the coast of Iceland and northern Europe during the summer where they mate.

Food Habits

To capture food, this shark swims with its mouth open widely, gillrakers straining plankton from the water. The absence of basking sharks in the winter has led to the belief that they hibernate in deep waters until the following summer and, since they lose their gill rakers in winter, possibly cease to feed during this time.

Economic Importance for Humans: Positive

This fish was once used for its liver oil and was thus virtually endangered for some time. It is still used in lesser amounts for fish meal and animal feed.

Economic Importance for Humans: Negative

In some areas, this shark is considered to be a nuisance because it gets tangled in floating nets while basking on the surface. Occasionally, they have been known to ram small boats, presumably by accident.

Conservation Status

No special status.

Contributors

Robin Street (author), University of Michigan-Ann Arbor.

Glossary

Atlantic Ocean

the body of water between Africa, Europe, the southern ocean (above 60 degrees south latitude), and the western hemisphere. It is the second largest ocean in the world after the Pacific Ocean.

World Map

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.

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.

oceanic islands

islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.

References

The Sharks of North America; Castro:1983.