In the sea, their only enemy is the shark, but when in groups, dolphins are not afraid of sharks, and will torment and often kill a solitary shark. Dolphins are amazingly agile and have athletic, muscular bodies that allow them to circle around a shark, dizzying and confusing it.
Natural predators include certain large shark species such as tiger sharks (Galeocerdo cuvier), dusky sharks (Carcharhinus obscurus), bull sharks (Carcharhinus leucas), and great white sharks (Carcharhinus carcharias). In Sarasota Bay, Florida, about 31% of dolphins have shark bite scars.
Just like we check under our beds for monsters, sharks check for dolphins before nodding off. That's right, the toughest kids on the undersea block swim in fear of dolphins. Here, we've compiled a splash of facts to tell you why.
The dolphins will slam their snouts into the soft stomach of the shark which leads to serious internal trauma. They also use their snouts to hit the gills of the shark. A well placed hit can cause enough damage to kill a shark. Often, the shark is frightened by the first blow and will swim away.
Predation. Dolphins have few natural enemies and some species or specific populations have none. The only predators that the smaller species or calves have in the ocean are the larger species of sharks, such as the bull shark, dusky shark, tiger shark and great white shark.
Biggest weakness: Pass coverage
Specifically of note, the Dolphins rank 23rd in pass defense DVOA against tight ends and 28th against running backs.
Dolphins face many threats including entanglement in fishing gear, ocean pollution, habitat loss and climate change. Ocean noise pollution from human activity like commercial shipping and military sonar poses another serious threat to the beloved marine mammal.
Sharks are often viewed as one of the ocean's top apex predators, but despite this rather prestigious classification, there's one marine animal that most sharks prefer to avoid crossing paths with entirely: the bottlenose dolphin.
In fact, they don't tend to seek out dolphins and appear to avoid them if they see too many at once, by going silent and staying submerged, he noted.
This myth is often associated with a shark safety tip: “If you see dolphins, it's safe to swim there because their presence scares away sharks.” This is simply not correct. In fact, sharks and dolphins are often found near each other for a simple reason—they eat the same food, and both go where the food is.
A shark would win in a fight against a dolphin. They are faster, larger, and more attuned to predation than others. Furthermore, their mouths are actually large enough to bite down on a dolphin and deal fatal damage.
While dolphins and sharks generally swim side by side "minding their own business," dolphins occasionally antagonize sharks when they feel threatened, Kajiura said. These more aggressive dolphins will ram sharks with their noses, or slam into them with the whole force of their bodies.
Dolphins have no sense of smell
Dolphins have olfactory tracts, but lack olfactory nerves.
In reality, dolphins have saved humans on many occasions. In two (sort of) similar incidents, one in 2004 and one in 2007, pods of dolphins circled imperiled surfers for over thirty minutes in order to ward off aggressive great white sharks.
A female dolphin may carry its deceased calf around for days, until the body is in such a state of decomposition that only the head or part of the body remains. New research published in the journal Zoology suggests that this behaviour is evidence that dolphins grieve for their dead.
Most dolphin species stick to a diet containing a variety of fish and other small aquatic life forms, such as squid, octopus, and crustaceans. The only dolphins known to hunt and eat sharks are the killer whale and “possibly” the false killer whale.
"If anything, since orcas are the largest member of the dolphin family, their intelligence is perhaps superior to other dolphins," she told me.
Do orcas have predators? Orcas are apex predators, which means they're at the very top of the food chain and they have no predators. Killer whales are some of the largest and most powerful animals in the ocean, and no other predator is able to challenge them.
The northern elephant seal and northern (Steller) sea lion have diets that are very varied. Both species are known for eating shark eggs, and the northern elephant seal is known to prey on adult sharks and rays too. Pinnipeds (seals and sea lions) aren't the only marine mammals that have snacked on a shark.
Slowly back away
Try not to thrash and splash around as you gradually swim backwards toward shore. "You must try and keep the animal in sight and very slowly and gently try and swim backwards and get into shallow water. Again, you've got to be careful -- large sharks can attack in very shallow depths."
Dolphins saving people
No one knows why, but dolphins have been saving people for thousands of years. Dating back to Ancient Greece, there are dozens of claims of dolphins rescuing people from sharks, helping drowning sailors, and guiding boats through rough waters.
Dolphins often show aggression by raking — scratching one another with their teeth, leaving superficial lacerations that soon heal. Traces of light parallel stripes remain on the dolphin's skin. These marks have been seen in virtually all dolphin species.
That's where the Navy's dolphin pods and sea lions come in. Navy spokesman Chris Haley says the animals have been defending the waters around the stockpile, holding roughly 25% of the United States' 9,962 nuclear warheads, since 2010.
Dolphins are hunters, not beggars, but when people offer them food, dolphins (like most animals) take the easy way out. They learn to beg for a living, lose their fear of humans, and do dangerous things.