You’re more likely to be struck by lightning than bitten by a shark. Millions of people swim in the seas each year. But an average of just 64 bites are recorded annually worldwide. Only about six of those are fatal. That’s according to the International Shark Attack File.
Still, many people fear and mistrust sharks. In truth, rather than worrying about sharks hurting us, we instead should fear for them. Sharks are vital to maintaining the oceans’ health and resilience. Yet since the 1970s, populations of the world’s sharks and their close cousins, rays, have declined by more than 70 percent. Scientists reported this in 2021. Today, one-third of shark and ray species are threatened with extinction.
Climate change, pollution and habitat destruction all take a toll on sharks. But their biggest peril is the humans who catch them. Overfishing has driven the decline of more than 90 percent of the 1,266 species assessed by the International Union for the Conservation of Nature (IUCN).
“Generally, people think that sharks are monsters — cold, unfeeling — and we don’t really have much compassion for them,” says Grant Smith. He’s managing director of Sharklife. It’s a research and education group in South Africa. “That just leaves them wide open to exploitation and harm.”
To save sharks, Smith and others believe we need to flip the script: Think of sharks as awe-inspiring wildlife instead of food or foes. This requires outreach about why sharks are more valuable alive than dead.
Animals at risk
Sharks, rays and skates are grouped together as the Chondrichthyes (Kon-DRICK-thees). The skeletons of fish in this class are made of cartilage, not bone. These fish come in all shapes and sizes. They range from the whale shark, the world’s largest fish, to the dwarf lanternshark, which can fit in the palm of your hand. They live all across the world, from tropical reefs to polar straits.
As predators, many sharks influence the entire food web. By eating fish, marine mammals and crustaceans, they keep populations of other animals in check. This, in turn, affects the growth of coral, algae and marine plants.
Sharks have survived on Earth for at least 400 million years. But their biology makes them especially vulnerable to threats such as overfishing. Why? They grow slowly and don’t reproduce until fairly late in life. The Greenland shark, the world’s longest-lived vertebrate, lives up to 400 years. Females, however, don’t breed until they are 150. Great whites can live to age 70 and females aren’t ready to have babies until they are about 15 years old. And while some sharks lay eggs, most give birth to only a few pups at a time after a long pregnancy.
This slow life cycle means sharks “can’t keep pace with how fast we’re removing them from the environment or how fast their habitat is changing,” explains Jodie Rummer. A fish physiologist, she works at James Cook University in Townsville, Australia.
Overall, we know very little about most shark species. That’s especially true for those that dwell in the deep. This lack of knowledge makes it challenging to protect them. Luckily, that’s starting to change as scientists learn more about sharks.
Researchers now discover about one new shark or ray species each month, says Rachel Graham. She’s the executive director of the conservation group MarAlliance. One-fourth of the more than 1,200 known species of sharks, skates and rays have been identified just since 2001.
Fishing sharks to extinction
Rima Jabado is visiting a rural village on the coast of Oman in the Middle East. She drives up to a port. Men there are unloading hundreds of dead sharks from their boats. The shark scientist smiles to disarm the skeptical fishermen. This is often how she begins her fieldwork. She’s out to catalog the hauled-in species and interview the fishermen.
Jabado chairs IUCN’s Shark Specialist Group. Across Africa and Asia, she and her colleagues identify, measure and collect genetic samples from dead sharks and rays.
“People thought I was kind of crazy,” Jabado laughs. “Not a lot of people are interested in spending days with dead sharks at a fish market.” But it’s an effective, if grisly, way to figure out what is (or was) in different parts of the ocean.
A global decline in sharks
The relative abundance of sharks and rays worldwide, as measured by fishing data, has dropped since the 1950s. This graph shows that decline by dividing the total weight of fish caught by the amount of effort it took to catch them.
For instance, from 2010 to 2012, she and her colleagues collected data at a bustling fish market in Dubai. That’s in the United Arab Emirates, another Middle Eastern country. Sharks there are auctioned daily for sale in international markets. More than 12,000 sharks here were identified from more than 30 different species. Many of them were destined for Asia, Jabado’s team reported in 2015 in Biological Conservation.
Talking with fishers and fish sellers also reveals how people use sharks and rays, Jabado says. In Mauritania, in West Africa, people catch many sharks each day but don’t eat them. Instead, people ship the meat to other countries in Africa.
Skins of critically endangered rays wallpaper elevators in luxury hotels in Monaco, a country in Europe. Around the world, shark liver oil is widely used in makeup and skincare products. And in China, the bodies of small sharks become chew toys for pets.
A 2024 IUCN report, led by Jabado, compiled data from 353 scientists in 158 countries. These show where sharks are caught and where they are shipped. Indonesia, India and Spain account for about one in every three sharks killed worldwide. The United States and Mexico round out the top five shark-fishing countries. The European Union imports nearly one-fourth of all shark and ray meat globally.
Only about one in four sharks are caught intentionally. The rest are what’s known as bycatch. They fall prey to the many nets, hooks and traps that had targeted tuna, cod, shrimp and other seafood.
Sadly, the demand for shark and ray meat has nearly doubled since 2005. As overfishing has cut supplies of other seafood, more people are turning to these sharks and rays as a protein source. And many rural communities depend on sharks for food and income. This creates pressure to overfish.
Shark fishing can be sustainable. But to do that, the animals must be responsibly harvested. And quotas must be set and enforced by authorities.
For instance, 85 percent of the volume of sharks caught in the United States are spiny dogfish. These sharks are certified as a sustainable seafood source by the Marine Stewardship Council. Commercial harvests of spiny dogfish are carefully monitored and regulated. This abundant shark, roughly a meter (yard) long, is mainly exported to the European Union for fish and chips.
Shark fins used to go into a popular soup in many Asian countries. But this has declined in the last 20 years due to media efforts that highlighted the gruesome practice of harvesting the fins. This led many nations, including China, to ban shark finning.
Another kind of fishing
One balmy April weekend off the palm tree–lined coast of Key West, Fla., dozens of excited anglers head out in boats. Each team’s goal: hook as many bull sharks as possible in two days to win the Spanish Fly Shark Tournament.
Catch-and-release tournaments like this one are popular in some countries. The United States, Australia and South Africa are among them. At these events, sport fishers hope to land a shark for the thrill of it. Between 2005 and 2015, more than 66 million sharks were hauled in by recreational anglers along the U.S. Atlantic coast alone.
Most sport-fishing rules require releasing an animal once it’s been landed, photographed and measured. But many sharks get injured or die in the process. When they are pulled up from the water, their internal organs can be crushed and their vertebrae damaged.
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A global review of catch-and-release research found that roughly one in every seven sharks, on average, will die after released. Some species, such as hammerhead or blacktip reef sharks, are more sensitive to fishing than others. Pregnant females of any species are especially susceptible to the stress of capture. It often leads to premature birth or the loss of the pregnancy. That’s according to a 2023 review in Conservation Physiology.
“Catch-and-release is still harm,” says Smith, of Sharklife. Many people would frown upon this type of sport for charismatic land animals, such as lions, he argues. “Would you be allowed to exhaust an animal and then suffocate it for a while, starve it of oxygen, take a few pictures, everybody says, ‘Good’ — and then let it free?”
If people were snapping gleeful photos with a dead or injured dolphin, Smith says, “there would be an absolute public outcry.” He hopes we can “close the public empathy gap” and treat sharks, too, with respect and compassion. He’s now advocating to change rules for recreational shark-fishing in South Africa in ways that would limit harm.
Turning fear into fascination
A dozen children play at a century-old family fishing camp on a sandy spit of Isla Partida. It’s off Mexico’s Baja California. Fathers and uncles sit in the shade mending fishing nets. These men are the fourth generation to make a living by chasing fish — including sharks — from dawn to dusk. Most hope their children will not follow in their footsteps.
Paloma AnilΓ³ CalderΓ³n LeΓ³n, 15, wears a T-shirt with a hammerhead shark. It’s the logo of a local conservation group, Pelagios KakunjΓ‘. Paloma wants to be a marine biologist when she grows up. Her mother, Ana LeΓ³n, and father, Malaeel Salgado CalderΓ³n, are all for it. “There are very few fish left today,” CalderΓ³n says. It takes more and more time and fuel to find sharks, he says. So there is little profit from fishing.
Now, CalderΓ³n hopes to get paid to study sharks instead of kill them.
His family is part of a project led by Pelagios KakunjΓ‘. It aims to train 30 fishers in Baja California as field technicians. Each will drive a boat to find sharks. Then they will collect blood and tissue samples. They also will drop cameras to collect videos and place sensors underwater to track temperature and water chemistry.
One species they’re searching for is the scalloped hammerhead.
“Coming to Baja in the ’80s and ’90s, … there were hammerheads everywhere,” says James Ketchum. He’s a shark ecologist who cofounded Pelagios KakunjΓ‘ in 2010. The collapse of shark populations in Baja was sudden, he says. By 2012, “there was nothing,” Ketchum recalls. “I was basically crying underwater.”
Scalloped hammerheads near Isla Partida declined by 97 percent in the last 50 years. Ketchum is part of a team that reported this, last year, in Marine Policy. Overfishing, they concluded, was the main cause.
In 2012, Mexico banned shark fishing from May through July. This protects vulnerable species during their breeding season. And sharks are starting to come back.
Last year, researchers captured and tagged a juvenile hammerhead for the first time in Cabo Pulmo National Park. That’s a marine protected area near the southern tip of Baja California.
Other fishers are joining the growing ecotourism industry. Baja is a world-class destination for swimming with or watching mako, blue, thresher and white sharks. Shark-related tourism generates more than $300 million a year globally. That number is expected to double in the next 20 years, according to the IUCN report.
A success story
Two scientists scuba dive in the teal water off the island of Rangiroa in French Polynesia. They are searching here, in the middle of the South Pacific, for great hammerhead sharks. When they spot one, they film the animal for identification. A laser plate measures its body at 4 meters (13 feet) long. Next, they deploy a spear gun to place a tracking tag on this fish. It also collects tissue for analysis. It’s a little like giving a human a shot with a needle; the shark swims away unharmed.
The three-year Tamataroa Project is supported by the groups L’Εil d’AndromΓ¨de and Gombessa Expeditions. The data it collects will help reveal why endangered great hammerheads gather off this island from December through April, what they eat and from where they’re migrating.
Over the last 70 years, populations of these sharks globally have dropped by an estimated four-fifths. Luckily, Rangiroa still has large groups of these sharks. The area also boasts abundant gray and blacktip reef sharks. Manta rays, stingrays and spotted eagle rays thrive here, too.
There’s at least one clear reason why sharks thrive here: A law banned shark fishing in 2006.
An analysis of nearly 14,000 observations collected by divers from 2011 through 2018 found an increase in the overall abundance of sharks and rays in French Polynesia, including here in Rangiroa. Divers sighted 20 species of sharks and seven species of rays. This demonstrates the fishing ban is helping endangered species recover, a 2023 study concluded.
Polynesians’ willingness to protect sharks stems in part from the “grand cultural link” between people and sharks, says Tatiana Boube. She’s a shark ecologist at the University of French Polynesia in Tahiti. “In Polynesian culture, mankind is at the same level as any other life.” For some Polynesian families, sharks are a totem animal.
French Polynesia’s success shows that the people who live closest to these animals need to be on board with keeping them alive, Boube says. It also offers hope that sharks will return in force to Baja and other coastal regions where local people are changing fishing practices.
Once people are committed to conserving sharks, they are more willing to create and uphold rules that help keep sharks alive, says Graham of MarAlliance.
The most positive sign that the currents might be shifting in the sharks’ favor, Graham says, is a change in attitude and behavior. She points to reactions from people in Belize in Central America as one example. “Instead of ‘Oh my god, I’m so scared. … They need to kill the shark,’” Graham says, “It’s ‘Oh my goodness, we got to see a great hammerhead! It was huge.” Now everybody is excited, in a good way.
Her grand vision is that everyone sees a shark every time they swim in the ocean. For that dream to come true, Graham says, “we need a shark hero in every community.”
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