Sharks have a fearsome reputation as ruthless killers, their razor-sharp teeth and powerful jaws the stuff of nightmares. But are they really as dangerous to humans as pop culture makes them out to be?
If you’re short on time, here’s a quick answer: While shark attacks do occur, they are actually very rare. Most sharks have little interest in eating humans.
In this comprehensive article, we’ll examine the facts about shark behavior and attacks to determine whether sharks can reasonably be considered friendly to humans. We’ll look at different species of sharks and their temperaments, analyze statistics on different types of shark attacks, explore why sharks occasionally bite humans, and provide tips for safely coexisting with these predators of the deep.
Shark Attack Statistics and Fatality Rates
Incidence of Unprovoked Attacks
Shark attacks on humans are actually quite rare considering how many people swim and surf in the ocean every year. According to research from the International Shark Attack File (ISAF), there are around 80 unprovoked shark attacks worldwide each year on average.
For perspective, that’s just a tiny fraction of the millions of people who enjoy ocean activities annually. Put simply, your chances of getting attacked by a shark are extremely low.
That said, certain circumstances can slightly increase the risk of encountering an aggressive shark. For instance, areas with large populations of shorebirds and seals tend to have more incidents since sharks may confuse humans for their usual prey.
Activities like surfing and boogie boarding also attract sharks due to splashing and arm movements resembling injured animals. But even in higher risk situations, attacks are still very uncommon occurrences.
Fatality Rate from Shark Attacks
Perhaps the most reassuring statistic about shark attacks is the relatively low fatality rate. According to the Florida Museum of Natural History, the worldwide fatality rate from unprovoked shark attacks is just under 10 percent.
This means that in about 9 out of 10 incidents, the victim survives with varying degrees of injury, often due to timely medical treatment.
Advances in emergency medicine have significantly improved survival rates over the past few decades. With rapid response, bleeding can be controlled, wounds repaired, and risk of infection minimized. However, precautions like avoiding swimming at dawn/dusk or with open wounds can further reduce risk of incidents and potential fatalities.
Declining Attacks in Recent Years
The frequency of shark attacks seems to have decreased in the last few years, contrary to popular belief. According to ISAF data, the 2010s saw an average of 84 unprovoked attacks per year worldwide compared to 93 per year in the 2000s.
Fatalities also dropped from 7.5 to 4.4 annually when comparing the previous and most recent decade.
Scientists have proposed several factors that may be contributing to the decline in attacks. Improvements in beach safety practices, advances in medical treatment, and greater public awareness about shark behavior in certain situations have all likely played a role.
But ultimately, the risk was already extremely low, and the recent decrease is just a bit of extra re-assurance that sharks pose minimal threat to beachgoers and ocean enthusiasts.
Shark Behavior and Tendencies by Species
Dangerous Sharks: Great Whites, Tigers and Bulls
The great white, tiger, and bull shark species have more reported unprovoked attacks on humans than other sharks. Their large size, speed, and sharp teeth make them formidable predators. Great whites in particular have a reputation for aggression, likely due to high-profile attacks and their portrayal in films like Jaws.
However, these species do not intentionally hunt humans. Most bites occur when sharks mistake humans for seals or investigate unknown objects out of curiosity. According to the Florida Museum’s International Shark Attack File (ISAF), unprovoked shark attacks caused an average of just 6 fatalities worldwide per year from 2013-2017.
While great white, tiger, and bull sharks top the list for unprovoked bites, their behavior depends greatly on the situation. Encounters in their natural habitat do not always lead to aggression. However, bites are more likely when sharks’ normal behavior patterns are disrupted.
Less Aggressive Species
The majority of over 500 known shark species are not considered threats to humans. Many mid-size and smaller sharks inhabit coral reefs and small ranges along coastlines. Species like blacktip, spinner, and nurse sharks tend to be curious but not aggressive in close encounters.
According to the ISAF, blacktip, spinner, and nurse sharks were together responsible for around 25 unprovoked bites worldwide from 2013-2017. In comparison great white sharks in the same period caused approximately 100 unprovoked bites globally.
Whale sharks, despite their massive size up to 18 meters long, feed only on plankton and small fish. They allow swimmers to approach them without showing signs of aggression. The basking shark is another enormous but docile filter feeder.
Why Sharks Occasionally Bite Humans
While shark bites on humans are extremely rare considering how many millions of people enter the ocean each year, what motivates these incidents?
According to marine biologists, sharks most often bite humans due to mistaken identity or curiosity. The splashing movements of swimmers and surfers can resemble injured prey animals. Sharks may also investigate unfamiliar objects in their domains out of instinct.
In some cases, shark bites occur under unusual circumstances. Activities like fishing and spearfishing may attract sharks with blood from hooked fish. Opportunistic bites can then occur. In addition, some bites arise from situations of self-defense when humans provoke sharks by capturing them or interfering with mating and birthing behaviors.
In the end, while a small number of shark species have more reported attacks, humans are not part of sharks’ normal diets. Caution is warranted in shark habitats, but in most cases they prefer to avoid contact.
Tips for Safely Coexisting with Sharks
Avoid Areas with Known Shark Activity
If you know an area has a lot of shark activity or sightings, it’s best to avoid swimming or surfing there. Sharks are more likely to be found near seal colonies, steep drop offs, sandy bottoms, and areas with runoff from streams and storm drains.
Pay attention to any warning signs or alerts from local authorities about increased shark activity in certain locations. Being aware of your surroundings and staying clear of hotspots will lower your chances of an encounter.
Stay Close to Shore
When you’re at the beach, swim, surf and play closer to shore if possible. Most shark attacks on humans happen in deeper waters farther away from land. It’s recommended to stay in water less than 10 feet deep.
Sharks tend to frequent deeper sections of the open ocean and are less common along the shoreline and in shallow reef areas.
Avoid Dusk, Dawn and Night Swimming
Sharks are most active at dawn, dusk and night when their prey is abundant. Limit ocean activities during twilight hours and avoid going in the water altogether after dark. Sharks’ vision and sense of smell improves after sundown, heightening the chance of an encounter.
Early morning and evenings are feeding times for many shark species, so it’s safest to stay dry during those high risk periods.
Don’t Wear Shiny Jewelry
It’s wise to remove watches, rings and other shiny jewelry before entering the ocean. The glint and shine of jewelry can mimic the flickering scales of fish, attracting sharks that mistake it for prey. Wearing or flashing flashy accessories increases the likelihood of grabbing a shark’s attention.
To be extra cautious, stick to plain swimwear and dark wetsuits without reflective logos or designs.
Conclusion
While the prospect of a shark attack rightly frightens us, we must remember that fatal shark attacks are extremely rare events. For our own safety and for shark conservation, we would do well to respect these apex predators and take reasonable precautions without vilifying them.
With greater understanding and a few safeguards, humans and sharks can peacefully coexist in the oceans.