Dolphins are not only the sweet-natured, lovable mammals we have all been led to believe. They also have a darker side—with some disturbing tendencies that may just surprise you! When you hear the word “dolphin,” you might picture a cute, silvery mammal frolicking happily in the ocean with his dolphin friends. Or perhaps you imagine a well-behaved trained dolphin at Sea World who is ever so happy to perform tricks for nothing other than a bit of a fish reward.
Since the 1964 TV show Flipper, the dolphin has been seen as a smart, sweet, and playful creature. I mean, at one point in our lives, didn’t we all want to grow up and be marine biologists so that our job could be to “play with the dolphins?”
While it’s true they are extremely intelligent (so much in fact that the U.S. Navy uses them), and they can be kind and playful at times, these beloved creatures have a darker side you might not be aware of. Here are ten reasons you may be happy you decided on another career.
Related: 10 People Killed By Animals You Wouldn’t Expect
10 They Can (and Do) Bite Humans
With 80 to 100 teeth, bottlenose dolphins have ample force to bite and tear their prey. But sometimes, they use those teeth to bite humans.
In 2012, an eight-year-old girl was bitten on the hand by a captive dolphin at Sea World in Orlando, Florida. The young girl was tossing fish into the dolphin’s mouth when she ran out and raised the paper plate up in the air. This is when the dolphin leaped out of the water and grabbed the little girl’s hand in its mouth. It then pulled her toward the water before letting go.
Wild dolphins also bite. According to the National Oceanic and Atmospheric Administration, dozens of bites have been reported, with people even being pulled underwater by wild dolphins.
One report includes a woman who started out by feeding a pair of wild dolphins. She then decided to jump in the water to swim with them. This proved to be a bad decision as one of the dolphins bit her leg and clamped down. The dolphin was not letting go, making the woman use force to rip her leg out of its mouth. Her actions caused injuries that landed her in the hospital for a week-long stay.
9 They Attack (and the Attacks Can Be Fatal)
Dolphins are not afraid to attack humans, and when they do, the attacks can sometimes prove fatal. An example is an attack from San Paulo, Brazil, in 1994.
Two men were on the beach and noticed a dolphin in the water swimming close to the shore. The men decided to walk into the water and approach the wild dolphin. At first, things seemed fine; the dolphin was floating on the surface and letting the men pet it. But then the dolphin turned and rammed both men. One of the men sustained internal injuries so damaging he sadly passed away. The most likely reason the dolphin attacked was that it was under stress. 
8 They Are Coordinated Assassins
Dolphins coordinate their attacks with one another, with each dolphin having a purpose in the hunt. One of the most popular methods dolphins use to trap fish is to corral them into a “bait ball.” The dolphins will act together and swim around the fish, closing in more and more so that the bait ball forms. As the fish swim in the small, tight area, the dolphins will take turns bombarding through the swarm, grabbing up prey as they go along.
If the dolphins live in shallower waters, the dolphins will work as a team and push the fish toward the shore. Once the fish are in place, the dolphins will thrust themselves on the shore. The force of their bodies forces the water (and the fish) to get pushed up with them. The dolphins simply open their mouths, and the fish slide right in.
7 They Hunt in Packs
While dolphin groups, or “pods” as they are called, are typically comprised of 10–15 dolphins, there may be more to the group when they hunt…a lot more. Hunting packs have been recorded to have 1,000 or more members. These are called “super pods” and would put fear into any prey they decide to pursue! 
6 They Beat Up Their Food
Remember your mom telling you not to play with your food? Yeah, dolphins didn’t get that message. And when they play with their food, things get downright violent.
One of the ways dolphins “play” with their food is called fish-kicking or fish-whacking. The name really says it all. In this method, the dolphins use their tail flippers much like a baseball bat to smack the fish. This sends the fish flying high into the air, leaving them stunned when they fall back down into the water. A stunned fish makes an easy meal. The dolphin simply swims over and swallows him whole.
Another meal they enjoy “playing” with is the octopus. Because the tendrils of an octopus can still be active even after death, the dolphins must make sure all the tendrils are inactive before consuming. They do this in a few violent ways.
The first way is to hold the octopus in its mouth, rise to the surface, and then slam the octopus down onto the water. They do this with such force that it breaks the octopus’s body apart. If that doesn’t work, with the octopus in its mouth, the dolphin will thrash its head side-to-side on top of the water, which also rips the octopus’s body apart. They will also toss the octopus across the water, thus breaking them into pieces.
5 They Murder Other Animals for Fun
Dolphins, unlike most other animals, seem to murder for reasons unrelated to food. Most of their aggression is directed to porpoises, although there is no known reason as porpoises are not a food source or rival dolphins in any way.
Emerging evidence shows that dolphins are “wielding their beaks as clubs and slashing away with rows of sharp teeth. They have been found to bludgeon porpoises to death by the hundreds.” With no known reason for the deaths, it might seem the dolphins might just enjoy the process, and that is dark!
4 They Kill Each Other’s Babies
In 2013, scientists from Savannah State University made history by being the first to record a wild bottlenose dolphin giving birth. Sadly, immediately after the birth, they also recorded two male dolphins attacking the newborn calf. Luckily this calf survived the half-hour attack due to its mom fighting so hard to defend it.
But other calves have not been so lucky. There have been reported cases of bottlenose dolphin calves being found that died from blunt force trauma and bite marks that match those of adult bottlenose dolphins.
3 Males Physically Assault Females During Mating
When male dolphins want to mate, things get ugly. And since the males work together and gang up, the females don’t stand much of a chance of warding off these attacks.
It starts when two or three (or more) males work as a team to chase one female and isolate her from the rest of the pod. In the process, the males will show aggression toward her by hitting her with their tails, charging, biting, or even slamming their bodies into hers.
The male dolphin will then make a sound calling the female over to him. If she ignores the call, the males will again threaten or attack her. These sessions can last for hours or even days. This whole mating ritual shows dolphins are not the sweet-mannered mammals we thought they were!
2 Dolphins Share the Way They Kill
Dolphins are great hunters, whether they are hunting in coordinated attacks or solo. They have an arsenal of varied techniques to choose from for different prey. What makes them freaky is that they can constantly add new methods to their arsenal. How? By learning from one another.
One technique that has been passed on from one to another is referred to as “shelling.” This process consists of chasing a small fish into a shell. The dolphin will then insert their beak into the shell and bring the whole thing out of the water. They will shake the shell, and as the water drains out, the fish falls right into their mouth.
With being able to learn from one another, dolphins are always able to evolve and hone their hunting skills, making them better predators.
1 They Can Be Jerks Just for Fun
When you are in the ocean and see dolphins jumping in the waves, you may want to go over and get a closer look. Think again.
On April 27, 2018, in Western Australia, Andrew Hill was on a paddleboard when a pod of dolphins appeared behind him in the surf. Hill tells the news, “Eight or nine of them decided to catch that wave and surf straight at me, which has happened lots of times in the past to me, and generally they just take off to one side left or right.”
Hill was a little winded but was able to get back on his board and did not sustain any injuries. He added, “It’s good to see dolphins. Surfers like seeing dolphins, but obviously, I’d prefer them to stay a little bit further away than they did yesterday.”
+ It’s Not All Dark and Dangerous
And it’s not just humans they like to have fun with. Sometimes, a dolphin will do something that is harmful to itself—but all in the name of a bit of fun. Dolphins like to find pufferfish, making a game out of “playing catch” and getting a little high from the toxins as well.