Sharks play a vital role in maintaining the balance of our marine ecosystems, but reports from the International Union for Conservation of Nature suggest that balance is in jeopardy.
With over 300 species of sharks and rays threatened with extinction, the repercussions for our oceans could be devastating.
Some shark species have already disappeared, like the Lost Shark, or Carcharhinus obsoletus, which was last seen over 80 years ago.
Even well-known species like the great white and Shortfin mako are now considered vulnerable to extinction, while others could vanish from the oceans within the next few years.
The 11 Most Endangered Sharks
The IUCN lists all the following species as critically endangered, which means they face “an extremely high risk of extinction in the wild.”
As few shark species thrive in captivity, once we lose their wild populations, we lose the species for good.
Not only would that mean a loss of diversity, but it could also lead to the collapse of ocean food webs, causing devastation for many ecosystems, fishing operations, and tourist destinations.
#1 Pondicherry Shark
The Pondicherry shark is so rare it was thought to be extinct as long ago as the 1970s.
A small, stocky shark, the Pondicherry grows to just three feet long but has adapted to survive in both freshwater and marine ecosystems.
The species’ versatility makes finding it extremely challenging. It could be hiding almost anywhere, from deep oceans to river systems and lakes.
In 2021, researcher Forrest Galante went on a mission to find the endangered shark, and although his attempts at catching one failed, he did manage to prove that the species still exists.
Sadly, in Sri Lanka only “five species of sharks enjoy legal protection,” and the Pondicherry isn’t one of them. To make matters even worse, the Pondicherry is easily confused with the unprotected bull shark, which is possibly how one ended up at a fish market.
Pondicherry sharks are social creatures that are said to hug while mating. Although affectionate in this regard, they’re ferocious hunters that use “a slapping gesture” to ward off other predators during the chase. They feed on a wide variety of small fish, crustaceans, and cephalopods.
Once widespread “throughout the coastal Indian subcontinent,” Pondicherry sharks were hunted for meat and caught in large numbers, decimating their population. Now, only 249 individuals remain, making it one of the most endangered sharks in the world today.
#2 Great Hammerhead
The great hammerhead is one of the world’s most iconic shark species and the largest of all hammerheads.
The IUCN started listing the great hammerhead as critically endangered back in 2018, but the United States National Marine Fisheries Service (NMFS) disagrees.
Many expected the great hammerhead to be added to the Endangered Species List earlier this year and were disappointed by the NMFS’s decision to leave it off.
According to the NMFS, the great hammerhead is “not currently in danger of extinction throughout all or a significant portion of its range,” nor is it “likely to become so within the foreseeable future.”
Great hammerheads have a much wider distribution than the Pondicherry, frequenting warm and temperate waters worldwide, and yet some research suggests there are just 200 individuals left in our oceans.
According to Kristin Carden, a senior scientist at the Center for Biological Diversity, the great hammerhead “has suffered a global population decline of more than 80% over the past 70 years.” Without protection, it could disappear altogether within a matter of years.
As an apex predator, the great hammerhead plays a critical role in maintaining healthy coastal ecosystems. As such, its “extinction would have a vast ecological impact.”
The great hammerhead is “vulnerable to commercial and recreational fishing” and often dies even if released after capture.
#3 Sand Tiger Shark
The sand tiger shark, also known as the ragged-tooth shark, has a global distribution that helps it maintain some level of sustainability.
It’s considered vulnerable internationally but is only critically endangered within specific areas, including the eastern Australian coast, the western Mediterranean, and Europe.
In these areas, the sand tiger is targeted for its fins, which are primarily used for specialty dishes like shark fin soup, but also find their way into pet food products under the disguise of “fish”, “ocean fish”, “white bait” or “white fish.”
Sand tiger sharks are creatures of habit, which makes it easier for fishing operations to target them. They are also relatively social, gathering in small groups to hunt and mate. Again, this makes them a more appealing and profitable target than more elusive and solitary species.
Although sand tiger sharks have some interesting adaptations that distinguish them from other species, they may not have developed the characteristics needed to secure their future.
Sand tiger sharks are one of the few that practice intrauterine cannibalism, with the largest embryos killing their smaller siblings before they’re even born.
Unfortunately, this practice means that only two pups survive the gestation period, making their reproductive rate extremely low.
#4 Scalloped Bonnethead
This is another species of hammerhead facing possible extinction. Considerably smaller than its cousin, the great hammerhead, the scalloped bonnethead has a much smaller range, with the majority of the population occurring in the eastern Pacific Ocean between Mexico and Peru.
The scalloped bonnethead prefers shallow waters with a sandy bottom, which puts the species under severe pressure from the fishing industry.
According to the IUCN, it “is captured in commercial and artisanal longlines and gillnets, and may also be caught in trawl fisheries.”
That pressure is exacerbated further by the degradation of mangrove habitats, which act as nursery grounds for young scalloped bonnetheads.
Scalloped bonnetheads are so rare that we know very little about them. They are thought to be the smallest of the hammerhead species, reaching lengths of around three feet, and are distinguishable by their “mallet-shaped” heads.
Just how many scalloped bonnetheads remain is something of a mystery, but as there weren’t that many, to begin with, the species has little room for maneuver and could disappear before we get the chance to understand it.
#5 Scalloped Hammerhead
The global population of scalloped hammerhead sharks is declining. In 2006, the IUCN listed the Northwest and Central Atlantic population of scalloped hammerheads as endangered. In 2018, their status was escalated to critically endangered.
The scalloped hammerhead’s decline is partly due to the demand for its valuable fins, which “can sell for more than 100 USD per kg in Hong Kong markets.”
Even with the shark fin trade banned in much of the world, the scalloped hammerhead remains in danger. Often caught in pelagic and coastal bottom longline fisheries, the scalloped hammerhead suffers “from high hook mortality.”
As a ram ventilator, the scalloped hammerhead must keep moving to breathe. If hooked on a long line, they are forced into inactivity, causing them to suffocate.
Around 91.4% of all scalloped hammerheads caught as bycatch are dead before they’re even brought onto the fishing vessel, making protecting them extremely challenging.
Scalloped hammerheads only reach sexual maturity at around 10 to 15 years old and live to around 30 years, giving the females just 15 years to reproduce.
Like many other shark species, scalloped hammerheads have a long gestation period, and comparatively small reproductive output, which makes it difficult for the population to recover once it starts to decline.
Hopefully, global efforts to protect and conserve this iconic species will have a positive impact.
#6 Ganges Shark
Like the Pondicherry, the Ganges shark was thought to be extinct for several decades. Then, a few years ago, an 8-foot specimen appeared at a fish market in Mumbai.
While it’s good to know the species still exists, finding it dead at a fish market is far from ideal. According to the IUCN, there are less than 250 Ganges sharks left in the world, which isn’t that surprising when you consider that they share their habitat with around 400 million people.
As their name suggests, the Ganges shark “is largely restricted to the rivers of eastern and northeastern India,” which are heavily populated by people. As a result, the Ganges shark is subjected to pollution and other human activities, including “dams, barrages, and irrigation projects.”
The fact that the Ganges shark enters freshwater systems leads to it being confused with the aggressive bull shark and has developed a “man-eating reputation” as a result.
Unlike the bull shark, the Ganges sharks is a true river shark that potentially spends its entire life in freshwater. With its limited habitat, late maturity, and small population sizes, it’s extremely vulnerable to extinction.
Although protected under Schedule 1 of the Wildlife (Protection) Act, 1972, without better research, understanding, and education, it will likely remain one of the most endangered shark species on earth.
#7 Daggernose Shark
The global population of daggernose sharks is precarious, to say the least. The IUCN declared the species critically endangered in 2006, and there’s little sign of it recovering.
Like the Ganges, the daggernose shark has a limited distribution, occurring in just a few primary habitats in Southern America. Its preference for in-shore shallow waters brings it into constant conflict with local fishing operations, whose use of potentially fatal gill nets has only increased in recent years.
Although protected, the daggernose shark was already “within the razor’s edge of extinction” back in 2016, and researchers fear it could now be facing “reproductive collapse.”
Female dagger nose sharks only give birth every other year after a gestation period of 12 months. Giving birth to litters of between two and eight pups, the daggernose is slow to reproduce, making it particularly vulnerable to extinction.
#8 Oceanic Whitetip Shark
In 2019, the IUCN reclassified the Oceanic whitetip shark as critically endangered after it noticed “steep population declines.” Unfortunately, that’s done little to protect the Pacific Ocean population.
Attracted by lures, Oceanic whitetips are often caught by longliner boats fishing for tuna. Although not targeted themselves, the rate at which Oceanic whitetip sharks are dying due to bycatch means “we’re taking them out faster than they can replenish themselves.”
Like many shark species, Oceanic whitetips only mature relatively late in life and have small litters averaging just six pups.
These characteristics make them vulnerable to overfishing, even though they were “once among the most common pelagic shark species in the tropics.”
#9 Shorttail Nurse Shark
When the IUCN assessed the status of the shorttail nurse shark back in 2018, it listed it as critically endangered. Since then, a few positive events have occurred that could help the species survive a little longer.
In 2021, marine scientists found evidence to suggest that this diminutive shark species had expanded its range by over 2,000 km.
Not only could that expansion help them avoid conflict with the fishing industry, but it also provided them with “some degree of protection,” as they’ve expanded into Mozambique’s Ponta do Ouro Partial Marine Reserve, a large coastal marine protected area.
More good news came in July this year when three healthy baby shorttail nurse sharks hatched successfully at the Tennessee Aquarium.
Shorttail nurse sharks survive surprisingly well in captivity, and you sometimes see captive-bred specimens up for sale.
While having a species alive in an aquarium is better than losing it altogether if the shorttail nurse shark disappears from its natural habitat, it could indicate that its coral reef habitat is also collapsing.
#10 Angel Shark
There are around 23 different species of angel shark, eight of which the IUCN lists as critically endangered, making it the “third most threatened family of elasmobranchs.”
With their flat bodies, angel sharks look more like rays than sharks but share similar anatomical features, such as the positioning of the gills, with other shark species.
Although they have an almost global distribution, it is shrinking rapidly, and “they are now considered locally extinct in the North Sea.”
Angel sharks are bottom-feeders that use their flat bodies and mottled coloration as camouflage, ambushing their prey from their hiding place beneath the sand. Unfortunately, this behavior causes them to become entangled in “trawl and setnet fisheries.”
The angel shark grows slowly and has “a two or three-year reproductive cycle,” making it vulnerable to extinction.
#11 Swellshark
There are 17 species of swell shark, of which four are critically endangered. The whitefin, Indian, reticulated, and Sarawak pygmy swell sharks are all facing possible extinction.
Swellsharks are a type of catshark, but they have a unique ability that sets them apart.
As their name suggests, when threatened, the swellshark can inflate itself using either water or air. Scientists believe this adaptation makes it “harder for predators to eat them” or pry them from rocky caves.
Although commercial fishing operations don’t target swellsharks, they are frequently “caught accidentally as bycatch in commercial lobster and crab traps, gillnets and trawl nets.”
FAQ
What Shark is Most Endangered?
The Pondicherry and Ganges sharks are both close to extinction, with less than 250 individuals left in the world.
What is the Least Endangered Shark?
There are 79 different species of ground shark listed as species of least concern. These include wobbegongs, carpet sharks, houndsharks, catsharks, and sharpnose sharks.
Where are Sharks Most Endangered?
Sharks are endangered all over the world. With many species being highly migratory, local restrictions don’t do enough to protect them.
The best way to protect these ancient species is by developing international conservation and management guidelines, but these are proving difficult to implement.
Conclusion
Over a third of the world’s shark species is at risk of extinction, and we’re running out of time to save them.
According to Dr. Richard Sherley of the University of Exeter in the UK, “For every 10 sharks you had in the open ocean in the 1970s, you would have three today.”
Although there are people who would welcome a world without sharks, the reality is that we need them. Without sharks, fish populations would explode, causing shortages of marine resources, including food. Algae and plankton would start to die off, followed by the fish, “leading to a collapse of the entire marine ecosystem.”
Sharks play critical roles in our marine ecosystems, making us more reliant on them than we realize. The more we can do to raise awareness and support conservation efforts, the better it will be for our future, as well as theirs.
Nicky is a British adventurer and animal lover who spends her time exploring the natural world and writing about her experiences. Whether on horseback, underwater, running, hiking or just standing with a fishing rod in hand, she embraces everything her adopted home of South Africa has to offer.