Greenland Shark

“The Greenland shark is considered the Methuselah of Sharks.”

The Greenland shark, called eqalussuaq by the Inuit people is famous for living to a great age. Biologists believe that this large, slow fish can live to be half a millennia old. Its longevity probably has something to do with the fact that it does everything slowly. It swims slowly. It reproduces slowly. It catches prey by sneaking up on them when they’re asleep and then attacking.

The oldest of these animals has been around since Shakespeare, the signing of the Declaration of Independence and the French Revolution and two World Wars, and all manner of human upheaval and doesn’t care. It was a female, who according to an estimation, was between 272 and 512 years old. “Slow and steady wins the race,” must be the philosophy of eqalussuaq!

4 Incredible Greenland Shark Facts!

• It is often parasitized by a copepod that has an affinity for its eyes. The copepod often blinds the shark but doesn’t affect either its overall health or ability to hunt.
• The Greenland shark isn’t ready to breed until it’s about 150 years old.
• The shark cuts chunks out of large carcasses by biting into it and rolling its jaw around.
• The female gurry shark is gravid for between 8 and 18 years before she gives birth.

You can check out more incredible facts about Greenland sharks.

Evolution And History

The earliest known presence of a Greenland shark, based on fossil records, was around 100 million years ago, during the Miocene era. It is believed they evolved from an ancestral sleeper shark found in the Arctic-Subartic region of Canada. All sharks evolved from the same species, which was a small, leaf-shaped fish that did not have any fins, bones, or eyes. It was from this ancient ancestor that we have the two main groups of fish found today. The oldest shark, considered the first true shark, was Cladoselache, which lived 380 million years ago.

Scientific Name

The Greenland shark’s scientific name is Somniosus microcephalus. Somniosus is from the Latin “somnus,” which means sleep, and microcephalus is New Latin for “tiny head.” While there is only one species of Greenland shark, they do belong to the family of sleeper sharks that includes 20 different species.

Types Of

While the Greenland shark is the only one of its kind, it does belong to a larger genus of sleeper sharks that has 20 different varieties. Some of these are:

• Pacific sleeper shark (Somniosus pacificus)
• Southern sleeper shark (Somniosus antarcticus)
• Little sleeper shark (Somniosus rostratus)
• Plunket’s shark (Scymnodon plunketi)
• Portuguese shark, or Portuguese dogfish (Centroscymnus coelolepis) 

Appearance

The Greenland shark can grow as long as 24 feet, which rivals the length of the Great White shark. Females are bigger than males.

The shark moves very slowly and even its rare bursts of speed only achieve about 1.6 miles per hour. It has the usual rough shark tegument that’s basically made out of teeth. Its skin ranges in color from light grey to blackish brown and sometimes shows spots or bands. The shark has a small head, small eyes, and small gill slits. The body is torpedo-shaped and has two dorsal fins and no anal fins. There are two fins on either side of the root of its tail and small pectoral fins. The shark has about 100 teeth, with 48 to 52 in its upper jaw and 18 to 52 in its lower jaw.

Behavior

Greenland sharks are solitary save the breeding season. Sometimes a group of sharks, called a shiver or a school will gather at a whale fall or the carcass of some other large animal. If a prey animal is small enough for the shark to eat it whole, it will come upon it, open its mouth, and simply suck it in. The gurry shark is often blinded by parasites but does not need its vision to help it find food. It can do this by smelling food, including rotting carcasses, in the water.

Habitat

The shark is found in the North Atlantic and Arctic Oceans though it’s been seen as far south as France and the coast of the southeastern United States. It can be found near the surface of the water and at depths of over 7000 feet.

Diet

The shark is an opportunistic carnivore and will eat just about anything it can digest. One of the more interesting facts about the gurry shark’s diet is that it’s not above scavenging for a meal. Its stomach contents have included parts of large animals such as moose and polar bears. At least one shark had managed to down a whole reindeer.

Predators And Threats

The Greenland shark is a huge animal, and though it doesn’t move fast, it is an apex predator and simply too big for other predators to handle. The exception to this, of course, is humans. Because it is overfished in places, its conservation status is vulnerable. Climate change also warms the cold waters it prefers.

What Eats The Greenland Shark?

Humans eat the Greenland shark, even though its flesh is toxic. It can be prepared in a way that makes it safe to eat.

What Does The Greenland Shark Eat?

The Greenland shark eats fish, squid, marine mammals such as seals and small whales, and carrion.

Reproduction And Life Cycle

No one has ever seen Greenland sharks mating, but females have been seen with scars from bite marks. This suggests that these sharks mate like other sharks, with the male grabbing the female with his teeth to hold her still as he fertilizes her eggs internally.

After the eggs are fertilized, they remain within the mother until they hatch. Then, the pups are born live after a gestation that can take as long as 18 years. It is believed that a female shark gives birth to 10 pups at a time, and they will not be able to reproduce themselves until they are at least a century old.

Once the young are born, they are independent. Given her extremely long lifespan, a female Greenland shark can have hundreds of babies.

In Fishing And Cooking

Though its conservation status is vulnerable, about 1000 of these sharks are still deliberately caught every year, and three and a half times that many are the victims of by-catch. Humans hunt the shark for its hide and its flesh and until recently, the rich oil in its liver. Though its flesh is toxic to humans, it can be treated in a way that leaches the toxins out of it. The dish made from this treated meat is called Hákarl.

Greenland Shark Population

As of 2021, there are probably tens of thousands of these sharks in the wild.

1. National library of Medicine, Available here: https://pubmed.ncbi.nlm.nih.gov/26277575/
2. National Ocean Service, Available here: https://oceanservice.noaa.gov/facts/greenland-shark.html
3. Wired, Available here: https://www.wired.com/2014/02/creature-feature-10-fun-facts-greenland-shark/
4. Wikipedia, Available here: https://en.wikipedia.org/wiki/Greenland_shark
5. Animal Diversity Web, Available here: https://animaldiversity.org/accounts/Somniosus_microcephalus/