Spinner shark

About the Spinner shark

The spinner shark is a species of requiem shark known for leaping out of the water and spinning up to three times in midair as part of its hunting strategy. It’s found in warm tropical waters around the world, except in the Eastern Pacific. It is commonly found near the shore and at depths of up to 100 m (328 ft), although it spends most of its time in shallower waters.

This species is sometimes mistaken for the blacktip shark due the black markings in their fins, but there are some ways to tell them apart. Adult male spinner sharks have anal fins with black tips; blacktip sharks’ anal fins don’t have a black tip. Spinners also tend to be more slender than blacktip sharks.

Their diet consists mostly of bony fish. Their spinning leaps happen when a spinner shark charges a fish school from underneath.

These sharks are viviparous and females give birth to 3-20 pups every other year. Neonates are about 60-75 cm/2.0–2.5 ft at birth. They grow up to 3 m/9.8 ft, but most adults are about 2-meters/6.6 ft long.

This species is targeted for its meat and fins and its commonly marketed as blacktip shark. They’re caught by commercial and recreational fisheries, which puts significant pressure on them. Fortunately, they grow relatively fast, and this makes them more resilient to fishing pressures. However, without proper management they could become threatened in the near future.

The low biological productivity combined with its schooling behaviour and tendency to occur in inshore waters make it susceptible to fishing pressure, although if the pressure is on the juveniles only, it can be sustainable. The species is taken as target and bycatch of industrial, small-scale, and recreational fisheries using a range of gears, including trawl, longline, and gillnets. Over the past three generation lengths (38 years), the population is estimated to have increased in the Northwest and Western Central Atlantic in response to management measures and to have undergone a minor reduction of 3% in South Africa. It is suspected to have declined by >30% in the Arabian Seas region over the past three generation lengths (38 years) and is inferred to have also declined in the Mexican Atlantic, Southwest Indian Ocean, West Africa, and Southeast Asia. In Australia, it is captured in low numbers in managed fisheries and likely to be sustainably fished. The Spinner Shark has low biological productivity and although there is less fishing pressure and managed fisheries in some parts of its range, most of its range occurs in areas of intensive and unregulated fisheries. It is suspected that the Spinner Shark has undergone a population reduction of 30–49% over the past three generation lengths (38–59 years) due to exploitation, and it is assessed as Vulnerable A2bd.

The species is used for the meat, fins, liver oil, skin, and cartilage (White et al. 2006, Ebert et al. 2013). The meat is valuable and sold both fresh domestically and dried and exported. Spinner Shark fins accounted for 1.2% of fin samples in Hong Kong and 7.9% of the fins traded from United Arab Emirates (UAE) to Hong Kong; as UAE is a trading hub, the fins could have been sourced from across the Arabian Seas region and eastern Africa (Fields et al. 2018, R.W. Jabado pers. comm. 8/4/2020).

Do you have images or videos of Spinner sharks?
Submit them to [email protected].

Spinner shark Gallery