Otherwise known as Carcharodon Carcharias, the Great White is considered to be the largest apex predator as they are at the top of the ocean food chain.
Often misunderstood and feared due to their ferocity and terrifying teeth, these creatures are actually very interesting. These sharks are highly important in maintaining a healthy ecosystem.
Evidence of Great White Sharks’ ancestors dates back more than 400 million years ago, making them even older than dinosaurs.
Over this time they have evolved to have six highly refined senses which even includes electromagnetism.
This is the ability to orient themselves within a magnetic field they generate themselves or from disturbances in the Earth’s field.
Scientists have often deliberated on the lifespan of the Great White shark. Recent research has disproved what we once thought.
Here we’re going to look at the current understanding of their lifespan and what potential threats there may be to their populations.
Anatomy Of A Great White Shark
The world’s largest predatory fish measures on average a whopping 4.5 to 6.4 meters in length and between 520 to 770 kg in weight.
Females come in a little smaller at around 3.4 to 4.1 meters long, which makes them still pretty big. Despite their large size, Great Whites can swim at a speed of up to 60 kilometers per hour when they are targeting their prey.
The most prominent characteristic of this shark is the teeth, which have been vilified on our screens for decades. With around 3000 triangular teeth it’s not hard to see why.
The teeth and jaw work together to create an extremely strong grip which can eat around 20 to 30 pounds of flesh in one bite meaning their prey don’t stand a chance.
Sharks aren’t born with this powerful jaw, it starts to develop in the first year of their life, so they tend to feed on smaller and softer animals before this.
Where Do Great White Sharks Live?
These sharks like to live in temperate waters (between 12 to 24℃) with lots of fish concentrated around Australia, New Zealand, South Africa, the North Atlantic and the Northeastern Pacific.
They may venture further in search of food, however, they can usually be found to return to these highly productive temperate waters.
Typically they are found in shallow waters, near the surface which is why they tend to get into altercations with humans.
On occasion, they have been found to travel into the depths of the ocean, with sightings occurring at 1000 meters (3280 ft).
Average Lifespan Of A Great White Shark
The age of a shark can be determined by counting the growth rings that have formed on the vertebrae. These rings are laid down year by year, similar to the way we measure the age of a tree.
Catch and release programs are also used to determine the age of shark however is much more difficult to carry out and is less precise.
As mentioned, scientists have only recently made the discovery of the true lifespan of this giant predator. Previously it was thought that Great Whites only lived between 20-30 years, but this is far from the case.
Research from 2014 found the real average lifespan is actually 40-70 years. This makes them the longest-living Chondrichthyan fishes. The oldest Great White shark ever recorded was 73 years old.
Although Great Whites can live as long as human beings, they are classified as ‘vulnerable’ by the World Conservation Union.
This is the red list in regard to endangered species. So, how do these enormous apex predators become endangered? One explanation may lie in their life cycle.
Life Cycle Of A Great White Shark
The life cycle of this creature can be broken down into five stages: pups, young of the year, juveniles, subadults and adults.
Pups are around one meter long when born and immediately swim off to fend for themselves, unfortunately this means that many do not survive past the first year of their lives.
Many sharks tend to remain near to their birthplace until they reach adulthood.
Growing slower than initally thought, it may take a Great White 15 years to reach adulthood which is another blow to their population numbers as many do not survive.
During adulthood sharks spend most of their time hunting for food which is no surprise considering the size of them. Unlike most animals, they don’t really sleep.
They rest or ‘nap’ instead, especially in the colder months when energy conservation is important. It is thought that these illusive creatures only rest for around 10% of the day.
Reproduction
Males reach sexual maturity at 26 years old with females taking a longer at 33 years old. Female sharks are pregnant for 12-22 months and usually produce between 2-14 pups.
Fertilized eggs hatch inside the female where the pups continue to grow before birth.
Cannibalism can occur with the offspring, the first hatched consume the unfertilized eggs as a form of nourishment until they are born.
Sometimes the hatched will eat their siblings too. This behavior is called oophagy and also occurs in other shark species.
The longer gestation periods and oophagy mean that females don’t end up producing enough offspring to sustain their populations.
Feeding Behavior
As you can imagine, these carnivorous giants can easily eat large mammals such as elephant seals and sea lions.
They are actually pretty important in keeping these numbers at bay, maintaining the balance of the ocean. Other food sources include dolphins, fish such as tuna and seabirds.
Sometimes described as opportunistic scavengers, the Great White will feed on carcasses of thinks like whales and basking sharks.
This extremely long surviving species has been known to feed on plankton, small crustaceans or whatever they can get hold of when times are tough, making sense as they’ve survived five mass extinctions on Earth.
Threats To Great White Sharks
Population data for these sharks is unreliable, but the general consensus between scientists is that the populations are rapidly declining. Broadly speaking, the biggest threat to the Great White shark’s lifespan is human activity.
Predators
Although you may not think it, the Great White shark does have a natural predator: the killer whale. There have been reports of Orcas killing Great Whites and eating their livers.
Researchers say they target the liver as they are high-fat and ‘delicious’. Threat from predation is real but does not cause as significant a population decline as human threats.
Overfishing
Overfishing is globally the biggest threat to the lifespan of a shark. Overfishing leads to a decrease in food sources for sharks and other marine life.
Getting caught in fishing nets such as big trawling nets results in the animals instinctively trying to struggle to break free which leads to suffocation or strangulation if not noticed. Many fishermen do not free the sharks.
Demand For Shark Products
Demand for shark based products such as the notorious shark fin soup mainly found in East and SouthEast Asia are slowly starting to decline, but this barbaric practice still occurs and has an impact on the population.
On the other hand, there has been a rise in popularity of shark meat in other areas of Asia.
Chinese medicine is a big consumer of shark products, which they believe filters out toxins from the body. Specific body parts and oils can be used in products such as cosmetics in certain countries.
Shark leather, teeth and jaws are among other popular parts of the body that are exploited for tourism and general human consumption.
Other threats include pollution, ocean acidification, climate change and coastal development. These all have a greatly damaging impact on the ecosystems where sharks live and hunt, making survival even harder.
Final Thoughts
The average lifespan of a Great White shark is 40-70 years old. Although they have a long lifespan various threats can limit this.
Their own reproduction rates and gestational periods slow down the process of producing enough young to boost population numbers.
Human activity is by far the biggest global threat to Great White sharks.
Overfishing and shark fishing means that many may not reach sexual maturity before they are fished which means they don’t have a chance to reproduce, further impacting their population numbers.
These misunderstood creatures live a very mysterious life and the majority of scientists still have no understanding of various behaviors and processes of these sharks.
It is important that we continue to protect them to further study them and for the preservation of their ecosystem.
We hope you found this article interesting and we have answered your Great White questions.
If you’ve never dived with sharks before, then we urge you to try it. My name is Mikayla Adams and I have swum with sharks six times so far.
The beauty of sharks up close and personal is too precious to put into words - there’s nothing like it that I’ve ever experienced. Not only that, but to be in close proximity to one of the ocean’s most ferocious predators is such a thrill!
