The most common form of defense is speed; dolphins are incredibly fast swimmers and can outrun most species of shark, meaning they are often able to evade attack by simply outswimming their opponent.
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.
The group of swimmers were saved by the dolphins. For 40 minutes the dolphins swam around the swimmers, slapping their tails on the water to divert the shark and keeping the people safe. The shark eventually swam away without attacking the dolphins or the swimmers.
Speed plays a vital part in the hunting capacities of the orcas and the great white, but it's safe to say that the orca is the faster of the two. It is the second fastest marine mammal and can reach up to 56 kilometers per hour(35 mph), while the great white cruises at around 40 kilometers per hour (15mph).
Hour after hour of small bite after small bite, the orcas would slowly whittle megalodon down. Still, if there were a single mistake, megalodon would easily dispatch the orca in a single bite, but another would always be there to take its place.
Although the great white shark has a fearsome reputation, in a straight fight it is outclassed by the orca. Not only are orcas much bigger, they are also smarter. Great whites are now known to be warm blooded but orcas still have much higher metabolic rates because they breathe air.
Some scientists believe that dolphins instinctively come to the assistance of other injured dolphins and that it's a small step for them to help humans too. However dolphins obviously realise that humans aren't dolphins. Some scientists think dolphins help humans merely because they are curious.
There are many harmless sharks that are perfectly safe to swim with. One of the most common and least dangerous sharks is the nurse shark. Nurse sharks are docile sharks and they grow to a maximum of 15ft long, compared to the equally-as-gentle whale shark (which can grow to around 62ft)!
Killer whale
Orcas are the real apex predators of the ocean. Killer whales may be the only animals on our list that actually prey on great white sharks. Otherwise known as orcas, these intelligent mammals belong to the dolphin family and are probably the top predators in the entire ocean.
Although dolphins may seem curious, many of their behaviors are often misinterpreted as “friendly” when they actually are, in fact, signs of disturbance or aggression. If a dolphin approaches you in the water, do not engage, pursue, or otherwise interact with the dolphin, and take immediate steps to move away.
DO NOT TOUCH the dolphins. If the dolphins want physical contact with people, they will initiate it. If you try to touch one dolphin, then all the dolphins invariably leave the area. Not only does this adversely affect dolphin behavior but it irritates the other people with your group since everyone loses on the swim.
Dolphins appear to have a special affection for pregnant women. They have been known to swim up to an expecting woman and make buzzing sounds near her stomach. This is thought to be because dolphins might be able to detect a pregnant woman's developing fetus by using echolocation.
In addition, research has found that large marine animals such as whales and sharks sequester comparatively large amounts of carbon in their bodies. When they die naturally, they sink to the seafloor, where they are eaten by scavengers.
Only about a dozen of the more than 300 species of sharks have been involved in attacks on humans. Sharks evolved millions of years before humans existed and therefore humans are not part of their normal diets. Sharks are opportunistic feeders, but most sharks primarily feed on smaller fish and invertebrates.
Fighting the Shark
Usually, a hard blow to the shark's gills, eyes or snout (end of its nose) will cause it to retreat. These are really the only vulnerable areas on a shark. If you have a spear gun or pole, use it! A sharp object is a good way to inflict enough pain to scare away the shark.
Dolphins also have the advantage of speed as they can swim faster than most shark species. Of course, the biggest advantage dolphins have over sharks is intelligence, especially through echolocation (when dolphins send sound waves through the ocean).
Some sharks such as the nurse shark have spiracles that force water across their gills allowing for stationary rest. Sharks do not sleep like humans do, but instead have active and restful periods.
Sharks and dolphins are two of the most formidable creatures in the ocean, but while sharks are often seen as fearsome predators, they are known to be intimidated by dolphins.
Great white sharks, to be exact. But the true ruler of the sea is the killer whale. Killer whales are apex predators, which means they have no natural predators. They hunt in packs, much like wolves, which are also at the top of their food chain.
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.
While the majority of dolphins in the US are bred in captivity, they are not domesticated animals. Pushing people into deeper water, head-jerking, and biting causing broken bones, skin abrasions, and other injuries have all been reported with direct contact interactions with dolphins.