Dolphins are excellent swimmers and can be seen swimming at high speeds. I have been researching their swimming techniques and wanted to share some research here.
Dolphins have many adaptations that allow them to swim. They have very little hair, few external appendages, a blubber layer that helps them float, along with powerful tails and short flippers.
Dolphins have adapted well to swimming due to evolution. I wanted to find out how they swim so well for their body size.
Adaptations
Hair
Hair is one of the defining characteristics of any mammal. However, the body of a dolphin has very little hair. The lack of thick hair allows the dolphin to swim through the water with less friction.
A dolphin’s smooth skin creates less water resistance while swimming. The body of a dolphin has little hair to disrupt or hinder water movement around their bodies.
Appendages
Any external appendages do not hinder dolphins’ movement through the water. The ears of a dolphin do not stick out to the sides like some mammals. The face also tapers at a specific point to enable the water to part in all directions, allowing it to flow smoothly around the dolphin.
Tails
Dolphins’ tails are filled with powerful muscles. These muscles move the whole body up and down in a smooth motion. As a result of this movement, the dolphins can move forward.
Dolphins swim differently from fish. Fish will move their bodies from side to side to propel themselves forward. Dolphins move their bodies up and down to be able to swim on.
The tail of a dolphin determines how fast the dolphin will swim. If the dolphin moves its body and tail more quickly, it will glide through the water more quickly. Dolphins use the tail fluke to control their direction while swimming.
They can also use their head to change direction as well. They will swim up by tilting their head to swim toward the water’s surface; if they tilt their head down, they will dive further downwards.
Blubber
Dolphins have a high-fat content called blubber. The blubber assists them in becoming buoyant. This fat layer allows them to float easier through the water, and on top of it, despite their weight.
The ability to float enables them to get to the surface quicker before they run out of air. Dolphins are mammals and need to breathe oxygen from the air.
Did you know there are 16 species of dolphins in North America? Find out what they are here.
Flippers
Dolphins have flippers on each side of their body. The flippers are used to steer the dolphin in the water. The fins are not used to propel the dolphin through the water.
The flippers also brake whenever the dolphin wants to slow down quickly. Dolphins also have a dorsal fin situated in the middle of their back, which stabilizes. The dorsal fin helps them to keep upright, avoiding a barrel rolling by accident.
Dolphins simultaneously use their tail and flippers to breach, flip, and jump from the water. When a dolphin moves to the water’s surface, they flick its tail powerfully to get adequate force to leap into the air. They also use the flippers to assist in directing themselves with flips and turns.
How do Dolphins Swim fast?
Dolphins can swim at a speed of up to 25 km per hour when trying to get away from danger or catch prey. They can keep this speed for a distance of 1500 meters. They can also swim at a rate of 7-8 miles per hour when carrying out regular tasks.
Researchers say that dolphins can also travel at a speed of 11-12.5 km/hr for extended periods. When the dolphin wants to move faster, they jump out of the water. This behavior allows them to save energy, as the friction of the water slows them down.
The swimming speed of a dolphin differs from one species to another. The bottlenose dolphin is said to travel at the highest rate of up to 20.5 km/hr, while common dolphins have 34.1 km/hr.
Other records of dolphins traveling at higher top speeds were due to that they were being pushed by the bow wave of a speed boat.
Since the 1930s, it has been a riddle to determine why dolphins swim so fast. It was until recently that scientists came to know all about dolphin speed. Controversial questions among scientists included how dolphins’ muscles can produce enough thrust for such high rates.
Frank Fish (real name), a marine biologist at West Chester University in Pennsylvania, said,” it has been controversial for a while” to establish how dolphins swim so fast.
A study published in the Journal of Experimental Biology experimented with two retired Navy dolphins. The two dolphins, Puka and Primo, swam through air bubbles.
The air bubbles were studied in their movement. Biologists could determine the forces they both generated by learning how the bubbles moved when the two dolphins swam through them.
The results indicated that a dolphin tail or fluke can produce enough thrust to speed the mammal through the water.
Frank Fish said that “the flukes are essentially wings; they generate a lift force that is directed forward, on both the upstroke and downstroke. Hence this produces the thrust that pushes the dolphin through the water so fast.”
This means that the flues are equally flexible and very important to enable the dolphin to maintain a highly excellent swimming range across a broad range of speeds.
The dolphins can control the fluke’s stiffness by changing the tension of the tendons in their tail.
Can Dolphins Swim Backwards?
Amazon River dolphins can swim backward. There is not much research on the behavior of this species of dolphin. However, they are assumed to swim in this position while searching for food or prey.
Why do Dolphins Swim Upside Down?
Dolphins swim upside down, but not all species of dolphins practice this behavior. The Commerson’s dolphin is a species that can often be seen swimming upside down.
They also display erratic swimming behavior, rarely swimming in a straight line. The Commerson’s dolphins can feed while swimming upside down.
Swimming in this unusual position gives the dolphins the advantage of swimming up on prey from below, trapping their prey between themselves and the surface of the water.
The Commerson’s dolphin ability to swim upside down gives them clear visibility of their prey.
Why do Dolphins Swim Alone?
It is rare to see dolphins alone, as they often travel in the company of others in large pods. However, sometimes, dolphins swim alone when traveling or migrating.
Dolphins swim to the water’s surface to save energy from the water’s friction on the submerged body. Dolphins swim alone to the water’s surface to orient themselves better to their surroundings. They also use this behavior to rid themselves of parasites on their skin.
How Deep do Dolphins Swim?
Only a few species of dolphin have been adequately studied over the years. Due to this, there is not enough data to tell us how deep all dolphins swim.
The bottlenose dolphin is one of the dolphin species which has been studied. These studies show that they dive to extreme depths. Bottlenose dolphins have been recorded swimming at depths of 300 meters (990 feet.).
Tuffy recorded this in 1965, a dolphin trained by the US Navy. As a side note, Tuffy was trained to locate lost divers and guide them to safety. The dolphin also carried messages and tools between the surface and an underwater habitat called Sealab II 200 (60m) feet below the surface.
Bottlenose dolphins do not always live in deep waters. The bottlenose dolphin prefers to live in relatively shallow water.
Why are dolphins mammals and not fish? Find out here
Conclusion
Dolphins have a fantastic ability to swim quickly, backward, and upside down. Their ability to swim fast assists them in escaping predators, while different positions aid in feeding.
Their body shapes, tail flukes, and the layer of fat each play a crucial role in allowing dolphins to swim well despite their weight. Dolphins have many unique adaptations enabling them to swim swiftly.
Although research on how dolphins swim is centered on the bottlenose dolphin species, many other species exist. There is an existing gap about why they swim backward and upside down.
Want to know why dolphins swim alongside boats? Find out here in an article I have written.