Fun Sixgill Shark Facts For Kids

Moumita Dutta
May 08, 2023 By Moumita Dutta
Originally Published on Aug 05, 2021
Edited by Jacob Fitzbright
Fact-checked by Ankit Shinde
Amazing sixgill shark facts which are very enlightening.

The existence of an extra pair of gill slits is a notable characteristic that distinguishes the cow shark from the rest of the sharks.

The cow shark, or Hexanchidae, comprises ten genera (some of it is extinct) and the species of sharks in this genera have one or two auxiliary pairs of gill slits, hence the genus Hexanchus, and this genus retains three species that are still surviving the bluntnose sixgill shark, the big-eyed sixgill shark, and the Atlantic sixgill shark.

The largest of all the order Hexanchiformes is the Hexanchus griseus which is recognized for its blunt snout, green eyes, six-gill slits, and single dorsal fin. These sharks inhabit temperate and tropical deep waters.

The Atlantic sixgill sharks are assumed to have eventually merged with big-eyed sharks, but the bluntnose sixgill sharks differ from big-eyed sharks on myriad factors.

Intrigued already? To know more about the sixgill sharks keep reading this article. We have more awesome articles like this, please check our articles on nurse sharks and basking sharks.

Sixgill Shark Interesting Facts

What type of animal is a sixgill shark?

The sixgill shark is a genus of sharks that are identified for the presence of one pair of extra gill slits and massive size found in temperate and tropical deep water.

What class of animal does a sixgill shark belong to?

The sixgill shark, or cow shark, belongs to the class of Chondrichthyes, the genus Hexanchus has three species: Hexanchus griseus, Hexanchus nakamurai, and Hexanchus vitulus.

How many six-gill sharks are there in the world?

The population of the sixgill sharks has reduced all over the world even though this species has a wide range of distribution, as this species of large shark is a victim of target fisheries. However, the total number of sixgill sharks in the world is not listed.

Where does a sixgill shark live?

The bluntnose sixgill shark (Hexanchus griseus) can be discovered in the range of the Atlantic Ocean, the Indian Ocean, and the Pacific Ocean within the 65-degree north and 48 degrees south latitudinal span.

Bluntnose sixgill sharks have a wide range of distribution and are observed even near the North American and South American regions, from the territories of North Carolina to Argentina, and from Alaska to Chile.

In the east Atlantic, the range of Hexanchus griseus is distributed from Iceland, and southern Norway to Nambia. In the Indo-Pacific, it is found from Northern Madagascar to Japan to the east of Hawaii, it is also located in Malta and Greece.

The big-eyed shark is found in the West Pacific and the Indian Ocean primarily, and the Atlantic sixgill shark is found in the Atlantic Ocean.

What is a sixgill shark's habitat?

These sharks are marine animals observed in the temperate and tropical deep water, the bluntnose sixgill shark (Hexanchus griseus) is nocturnal and frequently dwells in the upper slopes, 590–3,610 feet (179-1100 m) from the surface.

The range of depths may vary as it is even can be observed in water from 0–8,202 feet (0-250 m).

The Hexanchus griseus exhibits a vertical migration behavior as it is a strong swimmer, which is a phenomenon that occurs in highly migratory marine creatures where they swim and reach the upper slopes of the sea at night primarily to prey, and return to the bottom as soon as the daylight breaks.

Bigeyed sharks prefer a similar kind of habitat and display similar behavior to the bluntnose sixgill shark, but these shark species are found in the depths of 296 feet and 1968 feet (90 and 600m respectively).

Who does a sixgill shark live with?

This species of shark is a strong swimmer and exhibits diel vertical migration behavior. It is assumed that they are mostly solitary marine animals, however, this specific information is not yet known.

How long does a sixgill shark live?

The age determination of this species is tedious, but it is speculated that the average lifespan is around 80 years.

How do they reproduce?

The male sharks attain their sexual maturity at around 11-14 years, and the females attain sexual maturity when they are around 18-35 years of age.

The method of reproduction is mating, and ovoviviparous, which signifies that the females retain eggs inside their body until the eggs are prepared to hatch and the average litter size is 22 to 108 pups.

What is their conservation status?

The bluntnose sixgill shark (Hexanchus griseus), big-eyed sixgill shark (Hexanchus nakamurai), and Atlantic sixgill shark (Hexanchus vitulus) have a wide range of distribution all across the world, but these species become a victim of the target fisheries and hence the regional populations of these sharks are gradually depleting and their conservation status is Near Threatened as declared by the IUCN.

Sixgill Shark Fun Facts

What do sixgill sharks look like?

A dark, underwater view of the gills of a sixgill shark.

The largest amongst the Hexanchoid sharks is the bluntnose sixgill shark or Hexanchus griseus, the body is massive and the tail is long.

These sharks can grow approximately 120-168in (304.8-426.7 cm), while the body length of the males is around 120-132 in (304.8-335.2 cm) while the females have a body length of females is almost 120-168 in (304.8-426.7 cm).

The name of this species is derived from the structure of its blunt snout, the head is flat and broad and they have six-gill slits.

Their green eyes are one of their most remarkable features.

Another characteristic that distinguishes the Hexanchus griseus is the presence of a single dorsal fin which can be behind the insertion juncture or adjacent to the pelvic fins. The single dorsal fin is spherical apex while the pectoral fins are rounded towards the tips, and the pelvic fins also have rounded tips.

The color of the bluntnose sixgill shark may range from olive to grey to brownish hue, the upper part of the body is highly pigmented while the underside is comparatively pale along with the fins which are also pale.

Other than the single dorsal fin, six-gill slits, and blunt nose, another stand-out feature is the structure of their jaw.

Their jaw is massive, the lower jaw of a bluntnose sixgill shark consists of six teeth that appear like a saw on each side, and their upper jaw has nine small and uneven teeth which help them attack their prey effortlessly.

The big-eyed shark is not as big as the bluntnose sixgill shark and it is often confused with the Atlantic sixgill shark. The big-eyed shark is a medium-sized marine creature that reaches a maximum length of 72 in (182.8 cm) and weighs approximately 20kg and the Atlantic sixgill shark attains a size not more than 70 in (180 cm).

How cute are they?

Sharks are sea creatures with an intimidating appearance, which makes it difficult to define them as cute.

How do they communicate?

These sharks are generally solitary sea animals and it is deduced that they barely communicate and the only time they initiate the process is during the mating season when the males attempt to interact and persuade the females with the help of their teeth. This occurs from May to November when the males return to shallow water.

How big is a sixgill shark?

The size of these sharks depends on the species, the bluntnose is the biggest of all with a body length of which can be anywhere between 120 in (304.8 cm) and the largest it can get is 168 in (426.7 cm), the average size of a male bluntnose is roughly 120-132 in (304.8-335.2 cm) and the female is 120-168 in (304.8-426.7 cm), the bigeyed is considerably smaller than the bluntnose and has a body length of 72 in (182.8 cm).

The Atlantic sixgill shark can reach a maximum length of 70 in (180 cm) in their natural habitat.

The bluntnose is the largest of all the Hexanchoids.

How fast can a sixgill shark swim?

Sixgills are strong swimmers and present diel vertical migration behavior, but their accurate speed is not listed.

How much does a six-gill shark weigh?

The weight of these sharks depends on their sex and species, nonetheless, the approximate weight of the Hexanchus griseus can be anywhere between 440-880 lb ( 200-400 kg) and the Hexanchus nakamurai can weigh around 44lb (20 kg).

What are the male and female names of the species?

The male and female sixgill sharks do not have individual names based on their sex.

What would you call a baby sixgill shark?

These baby sharks are called pups, the average litter size is 22 to 108 pups and the precise gestation period is not listed, however, as these sharks are ovoviviparous the gestation period can be over two years.

What do they eat?

Sharks are carnivores and incredible predators, the Hexanchus griseus, and others, prey on other marine creatures such as mollusks, crustaceans, sea lampreys, dolphins, and hagfish. Their lower jaw contains saw-like teeth which help to devour their prey.

Are they poisonous?

There is no such evidence of them being poisonous, this species of shark does not pose potential harm to humans unless provoked, however, only one such incident of them being hostile or life-threatening towards humans has been recorded since the 16th century.

Would they make a good pet?

No, it is not an aquarium fish that can be domesticated, it is a marine animal and prefers its biological habitat.

Did you know...

The common name of the bluntnose sixgill shark is mud shark, other common names may include Atlantic mud shark, brown shark, and bulldog shark.

These species of shark have specialized organs which enable them to discover potential predators.

Do six-gill sharks have teeth?

Bluntnoses are recognized for their enormous jaw and unique set of teeth, there are six saw-like teeth present in their lower jaw, and nine, small, irregular teeth in their upper jaw.

How old are Sixgill sharks?

The sixgill shark is a primitive fish because it can be related to other sharks which are 200 million years old.

Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fish including frilled shark facts and Kokanee salmon facts.

You can even occupy yourself at home by coloring in one of our free printable six-gill shark coloring pages.

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Written by Moumita Dutta

Bachelor of Arts specializing in Journalism and Mass Communication, Postgraduate Diploma in Sports Management

Moumita Dutta picture

Moumita DuttaBachelor of Arts specializing in Journalism and Mass Communication, Postgraduate Diploma in Sports Management

A content writer and editor with a passion for sports, Moumita has honed her skills in producing compelling match reports and stories about sporting heroes. She holds a degree in Journalism and Mass Communication from the Indian Institute of Social Welfare and Business Management, Calcutta University, alongside a postgraduate diploma in Sports Management.

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Fact-checked by Ankit Shinde

Bachelor of Journalism and Mass Communication

Ankit Shinde picture

Ankit ShindeBachelor of Journalism and Mass Communication

Ankit is a Journalism and Mass Media graduate from the University of Mumbai. With experience in SEO, blog and article writing, and fiction writing, he is a versatile writer and content creator. In his free time, Ankit enjoys reading, writing, and listening to music.

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