Basking Shark

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Meet the largest fish in the St. Lawrence, the basking shark.

Cetorhinus maximus

White shark, great white shark, white pointer, white death, requin blanc (Fr.), grand requin blanc (Fr.)

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A lot of people are surprised to learn that the white shark frequents the east coast of Canada, and even the St. Lawrence. In fact, the white shark is observed more frequently in the Maritimes than in British https://cprpp.khm.gov.ua/ Columbia. The white shark is undoubtedly the best known and most feared shark. Its man-eater reputation, which comes from movies such as Jaws and from overly sensationalistic media reports, is false. However, this shark is considered dangerous and it occasionally attacks people.

On the East Coast, the white shark is present off all of the maritime https://transparencia.moralzarzal.es/ provinces. The majority of sightings and accidental captures have occurred in the Bay of Fundy. However, captures have also been reported off Nova Scotia, P.E.I., Newfoundland, and on the northern shore of the St. Lawrence Estuary. A white shark was even brought ashore at the wharf in Rivière-Portneuf, less than an hour from Les Escoumins, a popular dive destination in Quebec. Obviously, this was a very rare event. On the West Coast, most observations of the white shark have occurred off Haida Gwaii. No white shark has ever been observed by divers in Canada.

Basking shark (Cetorhinus maximus). Illustration © Jeffrey Gallant | ORS (All Rights Reserved)

White shark at Guadalupe, Mexico. — Requin blanc à Guadalupe, Mexique. — Photo Elias Levy (CC BY 2.0)

A white shark swims close to a pack of grey seals in the shallow water off Lighthouse Beach in Chatham, Massachusetts. — Un requin blanc nage près d'un groupe de phoques gris dans les eaux peu profondes au large de Lighthouse Beach à Chatham, Massachusetts. — Photo Mass. Office of Energy & Environmental Affairs (CC BY-NC 2.0)

White shark off Little Talbot Island, Florida, in March 2015. — Requin blanc au large de Little Talbot Island, en Floride, en mars 2015. — Photo FWC Fish and Wildlife Research Institute (CC BY-NC-ND 2.0)

White shark with a acoustic tag off the coast of Massachusetts. — Requin blanc avec un émetteur acoustique au large des côtes du Massachusetts. — Photo by the Mass. Office of Energy & Environmental Affairs (CC BY-NC 2.0)

White shark at Gansbaai, South Africa. — Requin blanc à Gansbaai, Afrique du Sud. — Photo Bernard Dupont (CC BY-SA 2.0)

White shark at Guadalupe, Mexico. Photo by Elias Levy (CC BY 2.0)

White shark at Dyer Island, South Africa. — Requin blanc à Dyer Island, Afrique du Sud. — Photo Olga Ernst (CC BY-SA 4.0)

White shark at Gansbaai, South Africa. Photo by Bernard Dupont (CC BY-SA 2.0)

Names

Scientific Name: Carcharodon carcharias* (Linnaeus, 1758)
Carcharodon: from the Greek [karcharos] = to sharpen + [odous] = teeth
carcharias: Greek [karkharías] = shark
*sharp-toothed shark

Common Names: White shark, great white shark, white pointer, white death, requin blanc (Fr.), grand requin blanc (Fr.).

White shark off the coast of California. Photo by James Maughn (CC BY-NC 2.0)

Size and Appearance

Maximum length: Up to 7.1 m (23′)
Average length: 4.5 m (14′)
Weight: Up to 2,300 kg (5,070 lbs)

The white shark is the largest carnivorous fish in the world. Although the Greenland shark rivals the white shark in length, the white shark has up to twice the girth and mass of a Greenland shark. A white shark measuring 5.23 m (17.17 ft) was captured off Prince-Edward-Island in 1983. Its age was estimated at 17 years based on the growth bands in its vertebra.

The white shark’s colouration and colour distribution enables it to blend into its environment and to attack its prey without being seen.

Dentition

The white shark’s teeth are large, triangular and serrated. Teeth in the lower jaw are slightly narrower.

A 2007 study from the University of New South Wales in Sydney, Australia, used CT scans of a shark’s skull and computer models to measure the shark’s maximum bite force. The study reveals the forces and behaviours its skull is adapted to handle and resolves competing theories about its feeding behaviour.^[96] In 2008, a team of scientists led by Stephen Wroe conducted an experiment to determine the great white shark’s jaw power and findings indicated that a specimen massing 3,324 kg (7,328 lb) could exert a bite force of 18,216 newtons (4,095 lbf).^[60]

White shark jaws. — Mâchoires de requin blanc. — Photo Bone Clones (CC BY-SA 3.0)

White shark tooth found at Baie-Trinité (Québec) on the northwest coast of the Gulf of St. Lawrence in 2019. — Dent de requin blanc trouvée à Baie-Trinité (Québec) sur la côte nord-ouest du golfe du Saint-Laurent en 2019. — Photo © Jeffrey Gallant | ORS

Distribution

The white shark has one of the widest ranges of any shark species. It is found from sub-Arctic to tropical conditions. In the Atlantic Ocean, the distribution of the white shark extends from Newfoundland to Florida. It has been documented as far west as Rivière-Portneuf in the St. Lawrence Estuary, which is less than four hours from Quebec City. The white shark routinely ventures into shallow water in search of marine mammals such as seals. The white shark traditionally appeared in the St. Lawrence for a brief period near the end of summer and early fall, but its seasonal excursions into the warming gulf and estuary now occur from at least July to October.

Provisional distribution map of Carcharodon carcharias based on research by the St. Lawrence Shark Observatory (ORS). Map does not include data from the U.S. To submit additional sightings or captures, please contact us.

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ALL OBSERVATIONS LOGGED AND VERIFIED BY ORS/GEERG.
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Prey

The white shark is an opportunistic predator that will eat just about anything that comes across its path, either dead or alive.

VERIFIED STOMACH CONTENTS

Fish: (Among many others) Atlantic salmon, hake, halibut, mackerel, tuna, other sharks and skates

Mammals: Large cetaceans (usually dead), dolphin, porpoise, seals, sea lions and other pinnipeds

Others: Birds, sea turtles

Predators

The only confirmed predator of the Greenland shark is the sperm whale (Physeter macrocephalus). GEERG has recorded two occurrences of a sperm whale exhibiting predatory behaviour while in the presence of the Greenland shark in the St. Lawrence Estuary. Unfortunately, the same whale – known as Tryphon – died of entanglement in fishing apparatus in 2009. Further investigation by GEERG’s Jeffrey Gallant (2009) led to the discovery of another potential indicator that this particular sperm whale could have been feeding on Greenland sharks for several years. Photo analysis revealed that Tryphon’s teeth were severely eroded from abrasion. The same dental anomaly was observed in a pod of orcas (Orcinus orca) feeding on Pacific sleeper sharks (Somniosus pacificus) off British Columbia in 2008.

The Pacific sleeper shark is practically identical to the Greenland shark. Orcas and sperm whales are believed to feed on sleeper sharks mostly for the large quantity of oil found in their livers. However, the hunters must first tear apart their prey with their teeth which are eroded by the sharp denticles that cover the shark’s skin. Feeding on sharks in this fashion over a period of several years would likely accelerate tooth wear thus transforming the predator’s normally sharp teeth into rounded stubs.

GEERG_Tryphon

(ABOVE) Sperm whale known as Tryphon sounding off Baie-Comeau in the presence of Greenland sharks. Video © Jeffrey Gallant | GEERG

Reproduction

Little is known about the white shark’s reproduction. It is ovoviviparous and it reaches sexual maturity at around 15 years. Although birth has never been observed, gestation is believed to last around 12 months. Females give birth to 2 to 14 pups measuring approximately 100 cm at birth.

Life Expectancy

Unknown. Believed to live at least 30 years.

Attacks

Attacks on humans attributed to the white shark in Canada are all associated with boats in the Maritimes. One man died from drowning after a white shark attacked the victim’s dory off Cape Breton (Nova Scotia) in 1953. No divers have ever been attacked by a white shark in Canada.

INCIDENTS

(1) In 1940, a wildlife officer was stalked by a Greenland shark while walking on pack ice at Basques Island in the St. Lawrence. The shark’s behaviour is consistent with that of an experienced seal predator.

(2) Around 1859, a human leg was reportedly found in the stomach of a ovo88 Greenland shark caught at Pond Inlet, on Baffin Island.

(3) A frequently told story is that of a family being attacked by a Greenland shark during a canoe excursion on the St. Lawrence in 1848. They only survived the attack by throwing an infant child overboard to distract the shark. Another version of the same story takes place aboard a kayak in the Arctic, which leads us to believe that both stories are more legend than fact.

Although the following are by no means attacks, thousands of victims of shipwrecks and war in the North Atlantic and the St. Lawrence – including the Empress of Ireland – may have been scavenged by the Greenland shark as it hovers just over the sea floor in search of food.

* The shark was not attracted by bait or caught on hook & line.

Fisheries

None.

Commercial fishing vessel anchored in Disko Bay, Greenland — Navire de pêche commerciale dans la baie de Disko, au Groenland — Photo © Jeffrey Gallant | GEERG

Guðjón Hildibrandsson and Jeffrey Gallant by the drying house at the Bjarnarhöfn shark-museum — Guðjón Hildibrandsson et Jeffrey Gallant près de la cabane de séchage au musée du requin du Groenland de Bjarnarhöfn — Photo © Emily Dowding-Smith | GEERG

Greenland shark meat inside the drying house at the Bjarnarhöfn shark-museum — Viande de requin du Groenland dans la cabane de séchage au musée du requin du Groenland de Bjarnarhöfn — Photo © Jeffrey Gallant | GEERG

Hákarl (kæstur), or fermented Greenland shark, from the the Bjarnarhöfn Shark Museum at a corner store in Reykjavik — Requin du Groenland fermenté dans un dépanneur à Reykjavik — Photo © Jeffrey Gallant | GEERG

Relation with Man

Unlike the god-like reverence for sharks prevalent in the South Pacific, Westerners hold little appreciation for these toothed monsters. Generally perceived as indiscriminate killing machines, this isn’t usually the case for the Greenland shark, at least not by certain fishers that mockingly call it the « bottom shark » and consider it to be completely harmless.

The Inuit long dried the Greenland shark’s skin to make boots and they used its teeth to cut hair. Sailors used its denticle-covered skin under their boots to prevent slipping on wet wooden decks.

To this day, certain fishers consider it a pest that damages their nets and that contributes to the decline of fish stocks. Pity the shark that is caught by these fishers who cut off their caudal fin and toss the shark overboard to a certain and pointless death.

The overall public perception on sharks isn’t much better. Thanks to sensationalistic documentaries and movies such as « Jaws », which largely prevailed until recently, few people have any sympathy for sharks although most gaze in awe at the sight of the beast hanging from a hook at the local wharf. Like them or not, few animals generate so much media frenzy and genuine fascination. GEERG aims to reverse this baseless and destructive trend with ground-breaking research and public-awareness.

Historical References

We have found numerous documented references of Greenland sharks in the St. Lawrence and the Saguenay Fjord dating as far back as the early 1800’s.

In 1922, the crew of a Newfoundland sealer stuck in the ice captured over 30 Greenland sharks after attracting them to the surface by emptying the bilges of seal fat and blood. The sharks hauled out of the water with gaffes measured between 3.7 m and 4.9 m (12 ft to 16 ft). Many other stories tell of similar experiences.

When beluga whales were still hunted on the St. Lawrence, dozens of Greenland sharks were often drawn to the killing grounds at high tide where the whales were gutted and bled to death in towns such as Bergeronnes. As the tide went down, the sharks became beached on the shoals and they too were sliced open by the fishermen in order to extract their livers for oil. When the tide came up again, some sharks, still alive and much to the surprise of their executioners, managed to swim back to the ocean where they survived for a short while longer.

Status

The Greenland shark is not listed as a threatened species by COSEWIC (Committee on the Status of Endangered Wildlife in Canada). However, its numbers in the St. Lawrence and Saguenay are still unknown.

The Greenland shark is listed as Near Threatened by the IUCN Red List (International Union for the Conservation of Nature and Natural Resources).

Click HERE to go to the IUCN Red List web page on the Greenland shark.