Did you know that there are sharks leaping high out of the water? One of them does additionally rather impressive spinning movements – thus its name: Spinner shark (Carcharhinus brevipinna).
The spinner shark or long-nose grey shark is a 6.6 ft -2 m- long requiem shark and looks like its relative, the blacktip shark, but has a black tip on its anal fin, too. It is common all over the world in warm-temperate and tropical waters, likes it nearshore as adults and has inshore nursery areas.
The body of the spinner shark is densely covered with diamond-shaped dermal denticles with seven (rarely five) shallow horizontal ridges, enabling it to swim agile and swift and leap high and spin fast. It feeds by rapidly swimming through schools of small fish while spinning and leaping and snapping its jaws in every direction to catch prey. The momentum at the end of these spiraling runs often carries it into the air, causing the spectacular spinning leaps.
The female spinner shark is ovoviviparous – each uterus is divided into a separate compartments for each of the 3 to 20 embryos. The embryos are initially sustained by a yolk sac. Later the empty yolk sac develops into a placental connection through which the mother provides nutrients for the remainder of gestation. This species has the smallest ova (relative to the fully developed embryo) of any ovoviviparous shark known. Females mature at 12 to 14 years old and give birth every other year after a gestation period of 11 to 15 months.
The spinner shark is, due to its small narrow teeth, not dangerous to humans, but can become excited by the presence of food and then can bit occasionally. Spinner sharks are targeted by commercial fisheries for the flesh, skin, liver oil and fins and by recreational fishers. They are listed as Near Threatened worldwide and Vulnerable in the northwest Atlantic.