Talk about the shark that humans fear most, the great white shark (Carcharodon carcharias) comes in mind. Of course, this is the shark that featured in the popular shark film Jaws derived from its novel by Peter Benchley. Here, this shark was depicted as a vicious human predator. Where humans may not be the favored prey of the great white shark, this shark holds the record of the highest number of reported shark attacks on humans.
The great white shark is a species of large mackerel shark found worldwide in all the major oceans. With its bullet-shaped body and jagged teeth, this shark is the largest known extant predatory fish. In fact, it is a primary predator of marine mammals up to the size of large baleen whales.
With an aura of danger surrounding this shark species, it is a great idea to learn the features, facts, and mysteries surrounding it. Thus, this page describes the great white shark while highlighting its amazing facts.
Common Names and Scientific Classification
Apart from “great white shark”, this species has other common names such as white shark, great white, and white pointer. The scientific name of this shark is Carcharodon carcharias, where the genus name is Carcharodon and the species name Carcharias. It is from the family Lamnidae commonly known as mackerel sharks. And, the order is Lamniformes.
The genus name Carcharodon comes from two ancient Greek words. These are kárkharos meaning “jagged or sharp” and odoús meaning “tooth” as Sir Andrew Smith described.
Habitat and Range of Distribution
Great white sharks inhabit most coastal and offshore waters. But, they are most popular in places such as South Africa, Oceania, Japan, Chile, the United States (Northeast and California), and the Mediterranean. Dyer Island, South Africa is one of the areas with a higher population of great white sharks.
This shark species is epipelagic, as such prefers the regions of the ocean with enough sunlight penetration. When observed, great white sharks prefer the concentration of games such as large bony fishes, sea lions, other sharks, cetaceans and fur seals. In the open ocean, this shark can go as deep as 3,900 feet (1200 m).
A recent study suggests that the great white shark is migratory, with the population in California migrating to the White Shark Café. This is a region between the Baja California Peninsula and Hawaii. They spend about 100 days in this area before migrating back, and they tend to follow some behavioral patterns. Thus, while migrating to the area they swim slowly and dive to depths around 3,000 feet (900 m). However, as they arrive, they only engage in short dives to depths around 980 feet (300 m), for about 10 minutes.
A similar study on a great white shark tagged in South Africa showed that this shark migrated to the northwestern coast of Australia and returned within nine months. Although it is not clear yet the purpose of this migration, experts believe it may have something to do with seasonal feeding or mating.
Appearance of a Great White Shark
The great white shark is a large bulky fish with a blunt torpedo-shaped body. This shark has a large snout pointing outwards. Its eyes are large just like other mackerel sharks, larger than other shark species in proportion to their body size. But the iris is deep blue in color instead of black.
The jaws are large containing sharply pointed, serrated teeth specially designed to tear flesh, puncture and shatter bones. When this shark bites, it shakes its head as such, sawing off a large chunk of flesh.
Great white sharks display countershading colors with a gray dorsal area contrasting with brown or blue shades and a white underside. This type of shading serves as a camouflage, as such, from the side it breaks up the shark’s outline making it difficult for preys to spot the shark. Also, from above, the gray color blends with the ocean, and below the white color shows minimal body outline as against the sun.
This shark has large dorsal and pectoral fins. The strong tail fin has upper and lower lobes of approximately the same size similar to some mackerel species.
How Large Does a Great White Shark Grow?
First, the female great white sharks grow noticeably larger than the males. Hence, an average female white shark will grow between 15 and 16 feet (4.6 and 4.9 m). While the males, on the other hand, will only reach between 11 and 13 feet (3.4 and 4.0 m).
The weight of an average adult of this species is between 1,150 and 1700 pounds (522 and 771 kg). Though, females can attain an average weight between 1,500 and 2,450 pounds (689 and 1,110 kg). More so, the largest females on record reach 20 feet (6.1 m) in length and weigh up to 4200 pounds (1900 kg).
At birth, great white sharks are around 3.9 feet (1.2 m) in length. Their growth rate averages 9.8 inches (25 cm) each year.
Among the living cartilaginous fishes, it is only the whale shark (Rhincodon typus), the basking shark (Cetorhinus maximus), and the giant manta ray (Manta birostris) in the respective order grows larger than the great white shark on average. These three larger species tend to be docile and are filter feeders against the predatory behavior of the white shark. Hence, making the great white shark the largest living macro predatory species.
Typical Behavior of the Great White Shark
Great white sharks on observation show complex behavior and social structure. This shark species in the South Africa region shows dominance hierarchy which depends on sex, size, and residents’ right. Thus, the females dominate the males, the larger sharks dominate the smaller ones, and the residents of a region dominates the newcomers.
Great white sharks engage in spy-hopping, this is the act of raising their heads above the ocean surface regularly to gaze at prey or other objects. This behavior has been observed in only very few shark species such as the black tip reef shark. Experts also believe that this shark might have learned this behavior from human interaction. Another speculation suggests that the shark smells better with its head above the water since smell travels faster in the air than in water.
From observation, great white sharks are very curious creatures, showing intelligence, and maybe social depending on the situation at hand. This shark species has shown a social structure of a clan as observed at Seal Island. They were arriving and departing in clans of two to six individuals and on a yearly basis. Members of a clan get along peacefully with each other, but whether they are related is unknown. Though it is clear that each member has a role to play with respect to rank, and each clan has a defined leader just like a wolf’s pack. And, when different clans meet, they tend to establish social rank through non-violent interactions.
Hunting and Feeding Behavior
Great white sharks are carnivorous species; thus, they prey on a variety of marine creatures. These include cetaceans, fishes, pinnipeds, sea turtles, and even seabirds. Juveniles of great white sharks predominantly feed on fishes and other elasmobranchs. This is because their jaws are not yet strong enough to hold the forces needed to attack larger prey. However, as they reach the length of about 10 feet (3.0 m), their jaw cartilage should be strong enough to withstand the impact of biting into larger prey.
As this shark species further grows to a length of close to 13 feet (4m), it starts targeting more of marine mammals as food. Also, there may be preferences depending on individual sharks. Great white sharks prefer prey with energy-rich fat content.
They also tend to feed opportunistically. During hunting, these shark species use rituals and displays to settle conflicts. They rarely engage in combats, though there are individuals found with bite marks identified to be of other white sharks. Why great white sharks will bite its own species is not clear, but there are suggestions it could be a warning bite for individuals that gets too close to another. Or, on another note, it suggests dominance by white sharks.
The hunting techniques employed by great white sharks depend on the prey they are pursuing. These sharks hunt mostly in the morning, at about two hours of sunrise. At this time, visibility is poor. They record more success within the first two hours, but as it approaches late afternoon, success rate reduces as they eventually stop hunting.
White sharks also scavenge on the carcass of whales which comprises an important part of their diet. Although this is rarely observed as whales die in remote areas, the sharks use chemical and odor detection to find the carcass.
From observing the stomach content of great white sharks, whale sharks may also be part of their diet. This includes both juvenile and adult whale sharks. However, it is not clear yet whether it is through active hunting or scavenging.
What is the Bite Force of a Great White Shark?
The bite force of the great white shark according to the experiment conducted by a team of scientists led by Stephen Wroe in 2008 indicates that a specimen weighing 7,328lb (3,324 kg) can exert a bite force of 4,095lbf (18,216 newtons).
Great White Shark Adaptations
Sensitivity
The extra sensation given by the ampullae of Lorenzini is present in the great white shark just like all other shark species. This sense helps the shark to pick up electrical fields produced by other living organisms.
Amazingly, the great white shark possesses advanced sensitivity that it can detect half a billionth-volt variations. Thus, at close range, this shark can even locate an immobile animal by detecting its heartbeat. The lateral line of fishes gives them similar sensation but not as developed as the great white shark’s.
Temperature Regulation
Another adaptation of this shark species is the ability to regulate body temperature, keeping it warmer than the surrounding water. This helps the shark to hunt fast and agile prey as sea lions more successfully. As the white shark can internally control its temperature, it can be considered a mesotherm.
Long-distance Migration
For long-distance migrations across poor nutrient areas of the ocean, great white sharks rely on the fat and oil stored in their liver. This adds to the shark’s capacity to maintain buoyancy with the liver.
Strong Immune System
The toxicity of heavy metals seems to have little negative effects on the white shark. The confirmation follows the examination of blood samples from 43 individuals of varying size, age, and sex. These samples were taken off the coast of South Africa. The result of the examination indicates high levels of mercury, arsenic, and lead in the blood, however, there was no noticeable increase in the white blood cell count and granulate to lymphocyte ratios. This is an indication of a healthy immune system of the great white shark.
Breaching of Great White Sharks
Breaching is the process by which shark jumps partially or completely out of the water and then dive back in. Great white sharks breach due to the high velocity they approach the surface of the water with. This shark tends to breach especially whilst hunting seals.
As the seals swim on the water surface, the great white shark launches an attack on its target from deep water. And, while moving toward the surface the shark can reach a velocity of 25 miles per hour (40 km/hr). This velocity launches the great shark out of the water as it gets to the surface. Sometimes, these sharks can jump as high as 10 feet (3.0 m) into the air.
Breach attacks of the great white sharks are not always successful, as only below half of the observed attacks proved a success.
Mating and Reproduction
This shark is an ovoviviparous species. Its embryos develop within eggs that hatch into the uterus and continue to develop there until birth. Not much information is available on the mating behavior of great white sharks. There is a possibility that sexually matured sharks meet at the location of whale carcasses for mating.
The gestation period of great white sharks lasts for 11 months with the jaws starting from the first month to develop. Embryos feed on the unfertilized ova produced by the mother shark in a process known as oophagy. Birthing takes place in the spring and summer periods. The maximum number of pups from a single mother of this species recorded is 14 pups. This was from a female measuring 15 feet (4.5 m).
What is the Maximum Lifespan of the Great White Shark?
Researchers recently believe that the male and female great white sharks reach sexual maturity at the ages of 26 and 33 years respectively. Whereby, the maximum lifespan reaches 70 years as stated in recent research by the Woods Hole Oceanographic Institution.
Examinations of the vertebral growth ring count resulted in males having a maximum age of 73 years, while the females have a maximum age of 40 years. This is for the specimens used in the study.
Interactions With its Natural Environment
Great white sharks in their natural environment tend to be the predator most of the times. However, they have a major threat which is the killer whale (popularly known as orca). The case mostly doesn’t turn out great for great white sharks especially in areas where the dietary preferences of both may likely overlap.
There are several incidents of killer whales attacking and killing great whites. A documented example is a case of the Farallon Islands off California, in the United States. Here, a female orca estimated to be around 15 – 17 feet (4.7 – 5.3 m) incapacitated a great white shark of length 10 – 13 feet (3 – 4 m). The process involved the orca inducing tonic immobility by holding the great white shark upside down and keeping it for about fifteen minutes causing the white shark to suffocate. Upon death, the orca ate the liver of the dead shark.
There are yet similar events, where killer whales impact great white sharks negatively. The orcas also generally impact the distribution of white sharks. As observed in the Farallon Islands, brief appearances of orcas resulted in great white sharks seeking out new feeding areas until the next season.
In all, there are yet occasional sightings of some great white sharks fearlessly swimming near killer whales.
Humans and Great White Sharks
Great white sharks have recorded great numbers of human encounters in several means of interaction.
Attacks on Humans
The great white shark, when compared to all other shark species, has by far the highest number of attacks on humans. In fact, as of 2012 there 272 documented unprovoked great white shark bite incidents on humans.
However, humans feared great white sharks the more after the best-selling novel by Peter Benchley, Jaws and the follow-up film adaptation directed by Steven Spielberg. This induced fear more than any documented bite incidents. Well, these works gave this shark the image of an excruciating man-eater. Though, great white sharks are responsible for 74 documented unprovoked bite incidents where the people involved died. These sharks may not really be what we take them for.
Why Do Great White Sharks Attack Humans?
Great whites in many of the bite incidents may not have targeted humans. Instead, they might just be test-bites as these sharks tend to bite unfamiliar objects to identify what it is. They also test-bite lifeless objects in the sea such as lifebuoys, flotsams, and other objects.
There are beliefs also that this shark species do not like human flesh. Probably because it is too bony for them. This follows the fact that in most bite incidents, the great white shark broke off contact after the first bite. Consequently, leading to a low proportion of fatalities when compared to overall shark attacks.
On the other hand, is also a counter hypothesis stating that the low proportion of fatalities has nothing to do with the shark not liking human flesh. Instead, it suggested that humans are often able to escape after the first bite, thus, making the attack unsuccessful. This was validated by the suggestion that a standard white shark attack pattern involves an initial devastating bite, which after, the shark waits for the prey to weaken before consumption. In all, we know that great white sharks attack humans, but the reason is only but speculations.
Attacks on Boats
Apart from human attacks, great white sharks have occasionally attacked and even sank boats sometimes. There are cases where they bumped or knocked people overboard, commonly biting the boat from the stern.
Why the shark’s attack boats are not clear, however, there are suggestions that the electrical fields generated by the boats attract them. Thus, the very sensitive ampullae of Lorenzini pick up the electrical field, and the sharks might get confused as to whether the prey is closeby or not.
Shark Control
Sometimes, humans take deliberate actions to reduce shark attacks through the process of shark control, also known as “shark culling”. This program involves the killing of sharks by a government. Environmentalists heavily criticize this approach as it causes harm to the marine ecosystem. More so, they see it as cruel, outdated, and ineffective because the techniques employed not only kill the target sharks but also kill many other marine species.
Shark control programs even while condemned by scientists is still existing of recently. Thus, great white sharks are currently killed alongside other shark species in shark culling programs in New South Wales and Queensland.
Shark Tourism
In areas where great white sharks are frequently swimming, there is a common practice of cage diving. Tourists go underwater in cages to swim with sharks. This practice is increasing in popularity and focuses on booming the tourist industry. To attract sharks, tour operators usually chum the water with pieces of fish.
Places, where cage diving is most common, include the coast of South Africa, Guadalupe Island in Baja California, and the Neptune Islands in South Australia. Great white sharks are frequent in these places. And, there are some financial leverages attached to the shark tourism industry in conserving this species.
Great White Sharks in Captivity
Keeping great white sharks in captivity is not easy because of the difficulty in getting them to eat. In the past, white sharks in captivity do not survive for long and eventually dies. However, more recently several public aquaria recorded long-term great white sharks’ exhibitions. Though, they were released back into the ocean after growing to a larger size.
No matter how successful the aquarists were in keeping these shark species, they still faced the problem of trying to get them to eat. Those that survived for some months managed to eat at some points. While others would not eat and constantly bump the aquarium walls.
Threats and Conservation
Great white sharks have killer whales (orcas) as a threat in their natural environment. Also, the increase in human fishing for this shark species poses a threat to them. It is not certain the population count or trend of this shark, and how much the threats caused the decline in its population. Nevertheless, the IUCN assessed this species as Vulnerable (VU) in their Red List of threatened species.
This assessment comes from the fact that the great white shark appears to be uncommon when compared to other widely distributed species.
10 Great White Shark Facts at a Glance
1. This Shark Has a Worldwide Distribution Excluding Antarctica.
While great white sharks occur on the coast of every continent in the world, they do not inhabit Antarctica.
2. They are the Largest Extant Predatory Fish
Since the sharks larger than the great white shark leans toward filter-feeding on small organisms, this shark as an active predator now assumes the position of the largest predatory fish.
3. Great White Sharks Can Feel the Heartbeat of Immobile Prey at Close Range
The electromagnetic receptors of this shark species are so sensitive that even if a prey decides not to move, the heartbeat will still be sensed by the shark. Thus, locating and striking it.
4. They Have Well-developed Sense of Smell
The great white shark can smell blood from up to three miles away in the water. Amazing!
5. Great White Sharks Also Scavenge
Apart from being active predators, these sharks also seek out dead animals and feed on their carcasses. For instance, carcasses of whales comprise an important part of their diet.
6. They Breach While Hunting Seals
Approaching the water surface with great speed in an attempt to capture seals, great white sharks tend to jump out of the water up to 10 feet above the surface and back in a process known as breaching.
7. Among the Fastest Predators in the Ocean
Great white sharks can reach a speed of 35 miles per hour making them one of the fastest predators in the ocean.
8. Great White Sharks Engages in “Spy-hopping”
Often, great white sharks will peak their heads above the water probably to track the smell of prey since smell travels faster in air. This is known as spy-hopping.
9. The Great White Shark has the Highest Shark Attack on Humans
Of all shark species, the great white is responsible for most attacks on humans. Although, most of these attacks are not fatal because the shark normally swims away after the first bite.
10. This is the Shark Depicted in Jaws
The best selling Peter Benchley’s novel Jaws followed by the film adaption directed by Steven Spielberg depicted the great white shark. However, this shark may not eat humans as the story portrays.
Further Reading
- “Great White Shark”, Wikipedia (edited 26 February 2020), Wikipedia.
- “Carcharodon carcharias (White Shark)”, IUCN Red List of threatened species.
- “50 Cool Facts About Great White Shark”, SharkSider.
- “White Shark (Charcharodon carcharias)“, Encyclopaedia Britannica.
- “Fun Facts About Great White Sharks”, Oceana USA.