Cold temperate to polar latitudes of the north Atlantic Ocean
Coastal to open ocean (associated with the bottom)
Near Threatened With Extinction
Order Squaliformes (dogfish sharks and relatives), Family Somniosidae (sleeper sharks)
Reaching lengths of 24 feet (7.3 m) and weights of 2200 pounds (1000 kg), the Greenland shark is one of the largest sharks in the ocean. Though both large and predatory, this species is not known to be particularly aggressive and is thought to be fairly sluggish in the cold waters of the north Atlantic Ocean.
Though they are sluggish and seemingly slow moving, Greenland sharks are top predators and eat a variety of fishes, invertebrates, and other prey. Dissected individuals have even had the remains of polar bears, reindeer, horses, and other large land mammals in their digestive systems. It is unclear whether these individuals had eaten live prey that fell into the water or if they scavenged dead animals, but Greenland sharks are known to live at the ice edge and to live at the sea surface. They are also known to live in very deep waters down to at least 7200 feet (2200 m). In the eastern north Atlantic, Greenland sharks can be observed or captured far inland in deep fjords. Some people believe that they may enter freshwater and may even be a contributor to the Loch Ness Monster myth.
Greenland sharks mate via internal fertilization and give live birth to relatively large young. Though they give live birth, Greenland sharks do not connect to their young through a placenta. Instead, during the gestation period, the embryos survive off of yolk sacs attached to each individual. This species grows incredibly slowly and may live to ages as high as 200 years old. Scientists believe that this species grows less than one centimeter (half an inch) per year after it has reached maturity; therefore, the largest Greenland sharks must be very old.
Because they are top predators in the polluted waters of the north Atlantic, Greenland sharks have meat that is laden with pollutants and is not safe for human consumption. Historically, there have been some commercial fishing operations to harvest this species’ livers for oil, and it is sometimes captured as accidental bycatch in fisheries targeting other species. Scientists believe that Greenland sharks are likely naturally rare and that they are near threatened with extinction.