The White Shark
Carcharodon carcharias (Linnaeus, 1758)

CONTENTS
Introduction
Names
Size and Appearance
Distribution
Dentition
Prey
Reproduction
Life Expectancy
Attacks
Fisheries
Status
References

INTRODUCTION

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 Columbia. The white shark is undoubtedly the best known and most feared shark. Its maneater 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 provinces. The majority of sightings and accidental captures have occured 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 occured off Haida Gwaii. No white shark has ever been observed by divers in Canada.

NAMES
Scientific Name: Carcharodon carcharias* (Linnaeus, 1758)
*sharp-toothed shark: Carcharodon comes from the Greek words "karcharos," meaning "to sharpen", and "odous," meaning "teeth".

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


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.

(Below) White shark (Carcharodon carcharias) at Isla Guadalupe, Mexico. Image © Terry Goss (Creative Commons)


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


(Above) Right side upper and lower teeth of the white shark. Image: RadCliffe (1916) Bull. Bur. Fish. Circ. 822

(Below) White shark measuring 5.23 m (17.17 ft) caught off Alberton, Prince Edward island in 1983. Images © Jack Woolmer
(ALL RIGHTS RESERVED / DO NOT REPRODUCE)




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 the island of Newfoundland to Florida. It has been documented as far west as Rivière-Portneuf in the St. Lawrence Estuary, only 40 km east of Les Escoumins, Quebec's most popular dive site. The white shark routinely ventures into shallow water in search of marine mammals such as seals. Its excursions into the Maritimes and Quebec normally occur in August and September. Less than 20 observations have been reported in the Pacific Ocean off British Columbia, mostly off Haida Gwaii.


(Above) Provisional eastern distribution map of Carcharodon carcharias based on research by GEERG. Details on observations (other than year) are available. Map does not include data from the U.S. or Europe. To submit additional sightings or captures, please contact us at: info@geerg.ca


(Above) Provisional western distribution map of Carcharodon carcharias based on research by GEERG. Details on observations (other than year) are available. Map does not include data from the U.S. or Europe. To submit additional sightings or captures, please contact us at: info@geerg.ca

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

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.

FISHERIES
None

(Below) Observing white sharks at the Farallon Islands, California. A 'suicidal' California sea lion greets the divers and makes friends with the fake sea lion used to attract sharks to the cage. Images © Jeffrey Gallant (GEERG.ca)

STATUS
COSEWIC (Committee on the Status of Endangered Wildlife in Canada)

Shark, White | Carcharodon carcharias | Atlantic population
Status: Endangered
Last Examination and Change: April 2006 (New)
Canadian Occurrence: Atlantic Ocean
Status Criteria: A2b

Reason for Designation: The species is globally distributed in sub-tropical and temperate waters, but absent from cold polar waters; hence Atlantic and Pacific populations in Canada are isolated from each other and are considered separate designatable units. This very large apex predator is rare in most parts of its range, but particularly so in Canadian waters, which represent the northern fringe of its distribution. There are only 32 records over 132 years for Atlantic Canada. No abundance trend information is available for Atlantic Canada. Numbers have been estimated to have declined by about 80% over 14 years (less than one generation) in areas of the Northwest Atlantic Ocean outside of Canadian waters. The species is highly mobile, and individuals in Atlantic Canada are likely seasonal migrants belonging to a widespread Northwest Atlantic population; hence the status of the Atlantic Canadian population is considered to be the same as that of the broader population. Additional considerations include the long generation time (~23 years) and low reproductive rates (estimated gestation is 14 months and average fecundity is 7 live-born young) of this species, which limit its ability to withstand losses from increase in mortality rates. Bycatch in the pelagic long line fishery is considered to be the primary cause of increased mortality.

Status History: Designated Endangered in April 2006.

Shark, White | Carcharodon carcharias | Pacific population
Status: Data Deficient
Last Examination and Change: April 2006 (New)
Canadian Occurrence: Pacific Ocean
Status Criteria: Not applicable

Reason for Designation: The species is globally distributed in sub-tropical and temperate waters, but absent from cold polar waters; hence Atlantic and Pacific populations in Canada are isolated from each other and are considered separate designatable units. This very large apex predator is rare in most parts of its range, but particularly so in Canadian waters, which represent the northern fringe of its distribution. There are only 13 records over 43 years for the Pacific coast of Canada. No abundance trend information is available for Pacific Canadian waters, or for adjacent waters in the United States that would permit a status designation.

Status History: Species considered in April 2006 and placed in the Data Deficient category.

REFERENCES
Benz, G W., Dippenaar, S M., 1998, Putting the Bite on Jaws: Copepods as Enemies of Sharks, Southeast Aquatic Research Institute.

Bigelow, H B., Schroeder, W C., 1953, FISHES OF THE GULF OF MAINE, United States Government Printing Office, Washington.

Borucinska, J. D., Benz G.W., Whiteley, H.E. 1988, Ocular lesions associated with attachment of the parasitic copepod Ommatokoita elongata (Grant) to corneas of Greenland sharks, Somniosus microcephalus (Bloch & Schneider), Journal of Fish Diseases ,21, 415-422.

Caloyianis N., Winter, 2000, Arctic Sharks - Adventures with the Greenland Shark, Ocean Realm.

Francis, M. P., S. Campana, and C. M. Jones. 2007. Age underestimation in New Zealand porbeagle sharks (Lamna nasus): is there an upper limit to ages that can be determined from shark vertebrae? Mar. Freshw. Res. 58:10–23.

Gallant J., Harvey-Clark C., Myers R.A., Stokesbury M.J.W., 2006, Sea lamprey (Petromyzon marinus) attached to a Greenland shark (Somniosus microcephalus) in the St. Lawrence Estuary, Canada, Northeastern Naturalist, 13, 35–38.

Harvey-Clark C., Gallant J , Batt J., 2005, Vision and its relationship to novel behaviour in St. Lawrence River Greenland Sharks (Somniosus microcephalus), The Canadian Field-Naturalist, Volume 119, Number 3. (July–Sept 2005).

Homer S., 1984, Jaws IV : Great white shark netted off Maritime tourist beaches, Equinox Magazine. 14, 127-128.

Joyce WJ, Campana SE, Natanson LJ, Kohler NE, Pratt HL, Jr, Jensen CF (2002) Analysis of stomach contents of the porbeagle shark (Lamna nasus Bonnaterre) in the northwest Atlantic. ICES J. Mar. Sci., 59:1263-1269.

Lineaweaver, T., Backus, R.H. 1970, THE NATURAL HISTORY OF SHARKS, Ed Lyons & Burford.

Martin, R. Aidan., Wallace, Scott., Wallace, COSEWIC Assessment and Status Report on the White Shark Carcharodon carcharias in Canada, COSEWIC COMMITTEE ON THE STATUS OF ENDANGERED WILDLIFE IN CANADA, 2006

Martin, R.A. 2005. Northerly distribution of the white shark, Carcharodon carcharias, in the eastern Pacific and relation to ENSO events. Marine Fisheries Review, 66(1): 16-26.

Martin, R. Aidan., 2003, Field Guide to the Great White Shark, ReefQuest Centre for Shark Research, Special Publication , 1, 1-185.

Martin, R. Aidan., 1995, SHARK SMART, ed Diving Naturalist Press, Vancouver.

Paccalet, Y., 2003, LA VIE SECRETE DES REQUINS, Ed l'Archipel, Paris.

Pranschke, J. L., 2000, The use of carbon and nitrogen isotope analyses for the determination of carbon source and trophic position of Somniosus microcephalus, Carleton University, Ottawa.

Ridoux V., Hall A.J., Steingrimsson G., Olafsson G., 1998, An Inadvertent Homing Experiment with a Young Ringed Seal, Phoca hispida, Marine Mammal Science, 14, 883-888.

Scott, W.B., Scott M.G., 1988, ATLANTIC FISHES OF CANADA, University of Toronto Press.

Stokesbury M.J.W., Harvey-Clark C., Gallant J., Block B.A., Myers R.A., 2005, Movement and environmental preferences of Greenland sharks (Somniosus microcephalus) electronically tagged in the St. Lawrence Estuary, Canada, Marine Biology.

Templeman, W., 1963, Distribution of Sharks in the Canadian Atlantic, Fisheries Research Board of the Atlantic, Ottawa.

Le naturaliste canadien, Déc. 1960. Université Laval

Les nouvelles du large, (Bulletin no. 7) - GREMM, 18.06.1999

Les nouvelles du large, (Bulletin no. 8) - GREMM, 24.06.1999