From a young age, we learn that dolphins are delightful mammals, joyfully leaping through the oceans and seas with their pods. They are often seen performing playful tricks in marine shows for a meal of fish and are renowned for their friendly interactions with humans, even saving lives from drowning or defending against aggressive predators. While these perceptions are accurate—dolphins are indeed intelligent creatures and are utilized by the U.S. Navy—they also possess darker traits that may surprise you. This article will explore some of these unsettling behaviors.

Dolphins Bite Humans

With around 80 to 100 teeth in their jaws, dolphins naturally use these to tear apart their prey. However, they occasionally use these teeth on humans. In 2012, an eight-year-old girl was bitten on the hand by a captive dolphin at SeaWorld Orlando, Florida, while feeding it. The dolphin suddenly lunged, grabbing her hand and pulling her toward the water before releasing her.

Wild dolphins also exhibit this behavior. According to the National Oceanic and Atmospheric Administration, there have been numerous reports of dolphin bites, with some dolphins even pulling people underwater. One report describes an incident where a woman feeding a pair of wild dolphins decided to swim with them. This decision turned out to be a mistake when one dolphin bit her leg, causing severe injuries and a week-long hospital stay.

Attacks on Humans – Sometimes Fatal

Dolphins are not averse to attacking humans, and these attacks can occasionally be fatal. In 1994, in São Paulo, Brazil, two men on the beach noticed a dolphin swimming near them and decided to wade closer. Initially, everything seemed fine, but suddenly the dolphin turned and collided with them. One man suffered internal bleeding and died from the injuries. It was speculated that the dolphin was under stress, which might explain the aggression.

Coordinated Attacks on Prey

Dolphins are known to coordinate their attacks when hunting. One common technique involves corralling fish into a “bait ball.” Dolphins swim together around the fish, gradually closing in until they form a tight cluster. The fish are then trapped, and the dolphins take turns feeding. In shallow waters, dolphins work as a team to drive fish towards the shore. As the waves return to the sea, the fish are swept into the waiting mouths of the dolphins.

Hunting in Groups

Dolphin pods usually consist of 10 to 15 individuals, but these numbers can swell during hunts. Some hunting groups have been recorded with over 1,000 dolphins, creating a formidable force that instills fear in any prey they pursue.

Playing Rough with Their Food

Unlike many animals that avoid playing with their food, dolphins engage in vigorous play with their prey. One popular method is “fish slapping,” where dolphins use their tails to smack fish into the air, causing them to spin and become disoriented upon hitting the water again. This makes the fish an easy target for the dolphins.

Octopuses are another favored plaything. Dolphins ensure that an octopus is inactive before eating it by keeping it in their mouths, bringing it to the surface, and then forcefully slamming it down to break its body. If this doesn’t work, dolphins may repeatedly slam their heads above water to tear the octopus apart.

Killing Other Animals for Fun

Dolphins sometimes kill other animals for reasons beyond food. Most of their aggression is directed towards manatees, despite manatees not being a food source or competition. Evidence shows that dolphins use their beaks and sharp teeth to inflict severe injuries on manatees, often leaving them battered and dead.

Killing Their Own Young

In 2013, a team from Savannah State University made history by recording the first documented dolphin birth. Unfortunately, shortly after the birth, two male dolphins attacked the newborn. Thankfully, the calf survived due to its mother’s protective efforts, but some other calves weren’t so lucky. Reports indicate that several deaths among young dolphins were due to body collisions and bite marks consistent with those from adult dolphins.

Males Physically Assault Females During Mating

When male dolphins seek to mate, their behavior can be aggressive towards females. Males often work in groups to isolate a female from the pod, using their tails, bites, or body slams to subdue her. The male dolphins may then vocalize to attract the female, and if she doesn’t respond, they may escalate their aggression. This process can last for hours or even days, revealing that dolphin mating rituals involve significant aggression.

Sharing Hunting Techniques

Dolphins are exceptional hunters, utilizing a variety of strategies to capture prey. They continuously develop and share new techniques, adapting their methods based on the nature of their prey. Their ability to learn from each other enhances their hunting skills, making them highly effective predators.

Heavy-Handed Playfulness

While seeing dolphins leap through the waves is a thrilling experience, it’s not always a positive interaction. On April 27, 2018, in Western Australia, Andrew Hill was paddleboarding when a group of eight or nine dolphins approached him. This was a familiar occurrence, but this time, one dolphin knocked him off his board and into the water. Hill was unharmed but remarked, “It’s great to see dolphins, and surfers love seeing them, but after what happened yesterday, I’d prefer they keep their distance.”