Can a dolphin eat a shark?

Following up on the general fascination with dolphins brutalizing sharks, I would like to take a minute and answer a question addressed to me by one of my readers.

Can a dolphin eat a shark?

The answer is yes and no. First of all, dolphins are carnivorous mammals so they eat meat. They persist solely on eating fish. They will eat shark if sharks are fed to them in small quantities. In fact, they will probably eat any other meat if it is "served" right.

At the same time, dolphins do not attack sharks with the aim to eat those. They eat relatively small fish which they can take in at once. They do not have the capacity to tear off chunks of meat from a large animal. So in reality, a dolphin cannot eat a shark, unless the shark is a very small baby shark. Even so, dolphin would probably prefer to eat the kind of fish they usually eat. It is very rare in the animal kingdom that you can introduce a new type of food to an animal which it will like a lot better than what it is used to.

Pictures of the frilled shark

So here are some pictures of the frilled shark.

A drawing of the frilled shark.

A photo of a stuffed specimen.

A line drawing of the frilled shark, showing its long body and face.

A frilled shark in a Japanese museum. It is called Rabuka in Japan.

Can a dolphin kill a shark?

So here is the question: Can a dolphin really kill a shark?

One thing is clear. Sharks can kill dolphins and sometimes they do. From Janet Mann's book Cetacean Societies: Field Studies of Dolphins and Whales, for example, we learn that at least a third of the examined bottlenose dolphins near Queensland had scars from shark attacks. Dolphins near the Natal coast of South Africa also had scars from shark bites. Dolphin remains in sharks' stomach are also known to be found. But, as Mann points out, no actual cases of sharks attacking dolphins have been observed.

But what about the other way around? We know that a dolphin would not eat a shark but can it inflict injuries that would result in death? In his book The Living Sea, Jacques Cousteau writes that "sea mammals can kill a shark by ramming it at high speed, as dolphins have demonstrated in oceanarium tanks." Now I am no expert in this field so I would have to take professor Cousteau's word for this.

In other words, sharks and dolphins can both be deadly to each other. The other interesting question would be whether they can be friends...