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Scientists have suspected for a while that Greenland sharks lived extremely long lives, but they didn’t have a way to determine how long. The age of other shark species can be estimated by counting growth bands on fin spines or on the shark’s vertebrae, much like rings on a tree.
- Overview
- Natural history
- Conservation status
Greenland shark, (Somniosus microcephalus), member of the sleeper shark family Somniosidae (order Squaliformes, which also includes the dogfish family, Squalidae) that is the longest-living vertebrate known. The species is primarily found in the cold-water environments of the Arctic Ocean and North Atlantic, from Baffin Bay eastward to the Barents ...
The Greenland shark is one of the largest cartilaginous fishes. It can reach a length of 7 metres (23 feet) and a weight of 1,025 kg (2,260 pounds) when fully grown, but most are between 2 and 4 metres (6.5 and 13 feet). Little is known, however, about how the species reproduces. Females are thought to reach sexual maturity when they surpass the 4-metre (13-foot) mark in length, which takes approximately 150 years to achieve. They are ovoviviparous (that is, eggs are retained within the body until they hatch) and produce an average of 10 offspring at a time. The type, amount, and duration of parental care the young receive are unknown, but scientists speculate that, like other shark species, Greenland sharks are independent from birth. No other vertebrate known has a life span as long as this species; radiocarbon dating of isotopes in the shark’s eye-lens nuclei suggests that the oldest Greenland sharks may be more than 500 years old.
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Greenland sharks are rarely encountered by humans. They are thought to prefer colder, deeper environments but may be found anywhere between the sea surface and depths of 2,200 meters (about 7,200 feet). Greenland sharks are slow-moving, typically swimming at rates of less than 3 km (about 1.9 miles) per hour. They are carnivorous, and their diet is often made up of several different types of fishes, including smaller sharks, eels, flounders, and sculpins. Crustaceans, seabirds, and carrion—as well as terrestrial mammals (such as horses and reindeer) that likely fell through the ice—have been found in stomach analyses of the species. Greenland sharks are not considered dangerous to humans, in part because they live in regions where people do not typically swim; the only known report of a possible attack by a Greenland shark on a person dates to 1859.
Greenland sharks are considered to be a near-threatened species by the International Union for Conservation of Nature. The species was valued for its liver oil; about 114 litres (30 gallons) of liver oil can be obtained from a large specimen (see also fish oil). (Although the flesh of the Greenland shark may be eaten, it is toxic unless properly cl...
- John P. Rafferty
21 de may. de 2021 · Using this method, scientists discovered Greenland sharks have a life expectancy of at least 272 years and could reach 392, give or take about 120 years. What’s more, these slow-growing...
Greenland sharks have the longest lifespan of any known vertebrate, estimated to be between 250 and 500 years. [3] They are among the largest extant species of shark, usually growing to between 2.4 and 7 m (7.9 and 23.0 ft) long and weighing between 400 and 1,400 kg (880 and 3,090 lb).
7 de ene. de 2022 · Life span: 272 years (estimate) Conservation status: Vulnerable. Greenland sharks have cylindrical bodies covered in teeth-like scales, called dermal denticles. These specialized scales...
- Patrick Pester
The rare and elusive Greenland shark is one of the largest sharks in the ocean. Though slow moving, they are top predators. Learn more and see how to protect them.
Reproduction and Life Cycle. Greenland Sharks have a slow growth rate and a long lifespan, with some individuals living for up to 400 years. The gestation period for Greenland Sharks is not well known, but it is believed to be around 2 years. Females give birth to an average of 10-12 pups, which are born at a length of around 35-50 cm. Ecology
