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A tagged spinner shark (Carcharhinus brevipinna).
The colored remains of the injected oxytetracyclin can still be seen around the tag below
the dorsal fin (see "Shark Research
Trip to the Gulf of Mexico" in this Shark Info).
© Mark Grace / Shark Foundation
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German: | Spinnerhai, Langnasenhai |
English: | Spinner shark, Longnose grey shark, Inkytail shark, Smoothfang shark |
French: | Requin tisserand |
Spanish: | Tiburon aleta negra |
Spinner sharks are a fast-swimming species of shark which often
jumps out of the water (hence the name!). The reason for their
“spinning” or spiral motion is the way in which they
catch their prey. Climbing quickly within a shoal of fish, they snap
on all sides while turning. Then they leap through the water’s
surface, making no attempt to slow down before reaching the top.
Spinner sharks are large and slender and have a pointed snout. The
first dorsal fin is relatively small and begins at the same height
as the end of the pectoral fin or slightly behind it. Spinner sharks
have no interdorsal ridge.
Their back is gray-bronze and their belly is white, and they have a
thin white band along their flanks. Very noticeable are the black
tips on both dorsal fins, pectoral and anal fins, as well as the
lower lobus of the tail fin. Individuals smaller than 70 cm have no
dark markings.
Western Atlantic: North Carolina down to Florida, the Bahamas, Cuba
and the northern Gulf of Mexico (probably missing in the Caribbean),
Brazil.
Southern Mediterranean: Off the coast of North Africa, Cape Verde
Islands, Sierra Leone down to Angola.
Indian Ocean: Southeast Africa, Madagascar, the Seychelles, the Red
Sea, the Gulf of Aden.
Western Central Pacific and also Australia. They are not found in
the island regions of the Pacific.
Spinner sharks have a wide range and make seasonal migrations. They
are found almost worldwide over the continental shelf, preferring
shallow waters (less than 30 meters), but have also been seen in
depths of approximately 75 meters.
Their average length is approximately 195 cm at a weight of 56 kg.
The longest spinner shark found to date measured 278 cm.
They feed mainly on fish, preferring swarm fish such as sardines or
herring. However, their food spectrum is very wide and also include
tuna, grunt fish, lizard fish, etc., as well as mollusks, small
sharks and rays.
Spinner sharks are viviparous and have a yolk sac placenta. They
bear between 3 and 15 pups which measure between 60 and 75 cm at
birth. Their gestation period is 12 to 15 months and the time of
birth varies depending on the location: the summer months for
animals in Senegal, Spring and early Summer in Florida and the Gulf
of Mexico. The young pups are born in coastal regions and grow
quickly.
The spinner shark resembles several other shark species which are
mostly only identifiable by specialists. The striking black coloring
of the anal fins is, however, one clear characteristic recognizable
in larger animals. This species is usually mistaken for the blacktip
shark (Carcharhinus limbatus) which, however, contrary to the
spinner sharks has a white anal fin with no black tip.
There have been no reports on accidents with spinner sharks.
Status unknown.
May be published only by indicating the source: Shark Info
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