Did you know that dolphins are extremely intelligent and their brain development is similar to that of humans? They have their own language, recognize themselves in a mirror, and show empathy. They even mourn their dead.
Dolphins are fascinating animals and universally loved by pretty much everyone. They are cute, playful, and always draw a crowd when they decide to surface.
Dolphins are spectacular animals full of magic and mystery. And those facts about dolphins we just went over hardly scratch the surface. Beneath the depths of the deep blue sea, these fun and friendly creatures will flip and splash their way into your heart. Read on to learn more about everyone’s favorite sea-faring friend.
Ready To Learn Dolphin Facts? Let’s Begin!
Dolphins are mammals found all over the world. Most of them live in shallow areas in warm and tropical oceans, but 5 species of dolphins actually live in rivers. River, or freshwater, dolphins predominantly live in South American and Asian rivers.
The most common dolphin, the bottlenose, is usually what people think of when they think of dolphins. If you’ve seen Flipper or a Dolphin Tale, you’re familiar with the bottlenose.
You can even take dolphin tours in areas where they congregate. They are often found in areas with beautiful clear water and shells.
Here are some additional fun facts about dolphins.
1. Dolphins Are Carnivores
Dolphins eat a wide variety of foods, including fish, squid, octopus, crustaceans, cephalopods, and other marine life.
Smaller dolphins usually stick to a diet of fish and other small prey. Larger dolphins, such as the killer whale (bet you didn’t know that a killer whale is actually a dolphin!) eat larger things, like sea lions, seabirds, sharks, and penguins.
To capture their food, dolphins often work together to surround and circle their prey in order to keep it from escaping. They keep circling until they have the prey forced into a small and dense ball. Once it’s trapped, the dolphins take turns swimming through the circle to pick off the fish who can’t escape.
Some other dolphins will work to force their prey into a corner or into a shallow riverbank or shallow water along the coastline. This makes it difficult for their prey to escape.
Dolphins do have teeth, but most of them don’t use them to chew their food and swallow it whole, head first, so the scales on the food do not disturb their throat. They use their teeth to defend themselves and to grip objects. They actually have two stomachs: one for food storage and one for digestion.
2. Dolphins Only Sleep with Half of Their Brain
Dolphins and whales sleep in an unusual way. Called “unihemispheric slow-wave sleep,” it basically means that they sleep with only half of their brain. When a dolphin goes to sleep, it shuts down one hemisphere of its brain and closes the opposite eye. This allows the dolphin to monitor what’s going on around them and to regulate breathing.
While they are sleeping, some dolphins are motionless at the surface of the water. Other times, they might swim slowly. Over a 24-hour period, each side of a dolphins brain gets about 4 hours of sleep.
Dolphins evolved into this sleeping style for a few reasons. They need half of their brain to control their breathing and also to watch out for danger while they rest. If they aren’t aware of their surroundings, they could be prey for bigger ocean predators.
Sleeping with half of their brain also allows certain physiological processes, like muscle movement, to continue. These processes help warm-blooded mammals, like dolphins, maintain the body heat they need to survive in the ocean.
3. Dolphins Live a Long Time
The life expectancy of dolphins vary, but the common bottlenose dolphin can live a whopping 20 to 50 years! To determine a dolphin’s age, veterinarians can count the rings inside each tooth. Each growth ring indicates one year of life.
Things that impact how long a dolphin lives include their habitat, diet, health status, species, geography, and their level of endangerment.
Dolphins in captivity generally have a shorter lifespan. Even though they are protected and well cared for, they still live a shorter time in captivity. Things like their diet, lack of a strong social structure, and a closed environment contribute to this shorter lifespan.
The most critical time for mortality is during the first two years of a dolphin’s life. This is when they are most susceptible to disease, predators, and adverse climate conditions.
4. Some Whales are Actually Dolphins
Orcas, which are very recognizable because of their black and white coloring, aren’t actually whales. In fact, they are part of the dolphin family. Sometimes called killer whales, they are the biggest members of the dolphin family and found in every ocean in the world.
Like dolphins, they are very intelligent and able to communicate. They coordinate with other whales in their pod to hunt their prey.
If killer whales are actually dolphins, why do we call them that? The name killer whale came from ancient sailors who observed orcas hunting and preying on other whale species.
They called them “asesina ballenas” which translates to whale killer. Eventually, the names were flip-flopped and the term killer whale was born.
5. A Dolphin Can Swim More than 20MPH
They didn’t call Flipper “faster than lightning” for nothing! Dolphins have been clocked at speed up to 25 miles per hour when they’re in a hurry or trying to get away from something. Their normal swim speed is about 7-8 miles per hour though.
To swim this quickly, dolphins use their tail, or fluke, to produce thrust to push them through the water. The flukes act as wings to generate a lift force that pushes them forward.
The flukes are flexible and dolphins can control that flexibility. As they swim faster, the fluke might become stiffer. Researchers are still trying to pinpoint how exactly they control the flexibility of their flukes.
6. Dolphins Do Not Have Hair
Dolphins have a few sparse hair follicles but any hairs that are present fall out before or quickly after birth. They don’t have any sweat glands either.
Their skin is usually gray to dark gray, smooth, and rubbery. The outer layer is the epidermis. The epidermis is extremely thick and constantly flakes and peels, just like humans. In fact, the epidermis of a dolphin is 10 to 20 times thicker than the epidermis of other mammals.
Their outer layer of skin is quickly sloughed off and replaced, keeping their body smooth and ensuring that they can swim efficiently.
7. A Group of Dolphins is Called a Pod
Dolphins live in social groups called pods. The number of dolphins in a pod varies, but can be anywhere from 2 to 15. Several pods might even join together for a few minutes or hours in open ocean water.
Mothers and their babies, called calves, stay together for 3 to 6 years and might even return to its mother to raise its own calves. Pods might be multi-generational or include both mother and calf pair, juveniles dolphins, and adult male dolphins.
Within the pods, there are often social hierarchies. Bottlenose dolphins, for example, show aggression and their dominance by biting, chasing, smacking their tails on the water, or body slamming other dolphins.
They can also exhibit aggression by raking, which is scratching one another with their teeth.
8. The Size of Dolphins Varies
The size of a dolphin depends on a number of different factors, like its sex, species, age, and where it lives.
The smallest dolphin is Maui’s dolphin, which does not get bigger than 5 and a half feet in length. The biggest dolphin is the orca, of course, which can be as long as 25 feet or more.
An average sized dolphin is about 8 feet long. River dolphins tend to be a little bit shorter; they can’t grow too long as their river habitat means that they have to be able to swim through small spaces and turn around sharp corners.
Males are generally larger than females and baby dolphins take many years to grow to adult size. On average, babies are between 2 and 7 feet.
9. Some Species of Dolphins Are Endangered
Some dolphins are plentiful in number, like the bottlenose. Other species are endangered and getting closer to extinction. The most endangered dolphins are Maui’s dolphin, Hector’s dolphin, Indus and Ganges River dolphins, and the Baiji.
Maui’s Dolphin
Maui’s dolphin doesn’t actually live in Maui. It lives off the coast of New Zealand and is the most endangered species of dolphin. The biggest threat is getting tangled in fishing gear.
Experts believe that the extinction of this species is imminent, especially if no action is taken to prevent the dolphins from becoming entangled.
Hector’s Dolphin
Hector’s dolphins also live off the coast of New Zealand, specifically in the shallow waters along the western shores of North Island. They are the smallest and most rare dolphins in the world. They have a unique look, with short stocky bodies, black facial markings, and a fin that looks like a Mickey Mouse ear.
Like Maui’s dolphin, they are also at risk for becoming entangled in fishing equipment. They are also threatened by water vessel traffic and pollution.
Indus and Ganges River Dolphins
The Indus and Ganges River dolphin live in the rivers of India, Pakistan, Bangladesh, and Nepal. Their numbers have been declining as a result of human activity.
Dam construction has destroyed their habitat and they are also threatened by pollution, entanglement in fishing gear, and depletion of their food supply due to over-fishing.
Baiji
The Baiji is considered to be functionally extinct. This means that during extensive surveys to count them, none were found. There might be some out there, but they have not been found.
The major threats to the Baiji is human activity. Fishing net entanglement, pollution, and destruction of the habitat all contribute to this extinction.
10. Dolphins Can Hold Their Breath Much Longer Than Humans
Most dolphins can stay underwater for as many as 8 to 10 minutes. Some species can even stay underwater for up to 15 minutes.
They breathe through a blowhole that gets covered by a muscular flap when they go under the water. This keeps any water from getting into their lungs.
The composition of dolphins’ lungs is different than humans. This is what allows them to hold their breath longer. Dolphin lungs contain more alveoli, which are tiny air sacs. Most mammals only have one layer of oxygen-carrying capillaries, but dolphins have two layers.
The membrane surrounding the lungs in a dolphin is elastic and thick, which means that they have a more efficient transfer of gases from their lungs to their bloodstream.
Dolphins also use selective circulation when they dive. The blood flow to their skin, digestive system, and extremities slows down or stops when they go underwater. Their heart, brain, and tail can still function.
The pressure of going down deep into the ocean forces air out of their lungs and into their nasal passages. Dolphins can squeeze out every last bit of oxygen to stay down as long as possible.
11. There Are Forty-Three Different Species of Dolphins
Dolphins aren’t just the grey medium-sized sea mammals that you see in the movies like Free Willy and Blackfish. There are in fact forty-three different species, six of which are found in fresh water.
The dolphin species come in a variety of fun colors like black, white, blueish, and sometimes even pink! Their color comes from their diet and environment.
The best-known species of saltwater dolphin is called the bottlenose dolphin. That’s the simple grey dolphin you see in Dolphin Tale. While the best-known species of freshwater dolphin is called the Amazon River Dolphin, a much larger and odd looking species.
12. Dolphins Work Together for Their Meals
Depending on the species, a dolphin can have as many as a hundred teeth. You would think that would make them a fierce predator. But they don’t chew their food. Instead, they use the teeth to hold the fish and then they swallow it whole. That means that they can only eat small to medium size fish.
Large dolphins are able to eat hundreds of pounds of fish a day. And since they never fully sleep, they require a lot of calories to stay full. To ensure they get enough food, they work together swimming as a pod to round up schools of fish and force them into a tight concentration so that they can plow through the fish and take as much as they want.
They also have other group hunting strategies like kicking up a lot of the mud or sand in the bottom of the water to camouflage themselves from the fish and make a net of sorts.
13. There Are Dolphins in the Amazon River
The Amazon River dolphin is also known as the “Boto” and is well-known for its pink skin. But they also come in shades of grey. Their color comes from a variety of different factors including their behavior, how close their capillaries are to the surface, their diet, and how much sunlight they are exposed to.
Their color can increase when they get excited, in a similar way to the way humans blush. They are around nine feet long and weigh about four hundred pounds when they are fully grown to make them one of the largest species of dolphin. They can live up to thirty years in the wild.
This species of dolphin is more solitary than others, typically traveling in pods of two to four. But in food dense areas of the river, it is more common to see them in larger groups.
Amazon River dolphins are also more agile than other species since the vertebrae in their necks are unfused allowing them to turn their head a full 180 degrees. This is so that they can swim through underwater obstacles like tree trunks, rocks, and large shells.
14. Dolphin Skin Is Especially Vulnerable to Environmental Elements
Dolphin skin is very unique. If you’ve ever had the opportunity to pet one, then you know that it has a soft and smooth feel kind of like a slippery river rock. This softness comes from how quickly the skin cells are able to regenerate on the surface of the dolphin. They slough off their skin all of the time and can regenerate it in as little as two hours.
Since dolphin skin cells are so active, they also react a lot to pollutants. In fact, in Sarasota, there is evidence that bottlenose dolphins are being exposed to chemical compounds from consumer products. These chemicals are known to cause cancer in humans.
If you care about dolphins, then you should take as many steps as you can to reduce your plastic use and avoid putting harmful chemicals into the environment. These magical creatures are not able to protect their own homeland, and it’s up to us as humans to realize what we are doing to their environment before they become extinct.
15. They Are Highly Intelligent
Scientists that study dolphins believe that their intelligence rivals that of a human, or that they may be even smarter than us. By using a two-way mirror, they can perform experiments and study to see how they respond to them.
Have you ever put your pet in front of a large mirror? While animals like cats and dogs generally don’t respond to mirrors at all, dolphins are much more interested and will play in front of the mirror for hours.
Dolphins are also able to recognize that they are looking at themselves rather than seeing another one of their species from the age of around six months old making them an incredible smart species. To prove this is what’s happening, scientists came up with an experiment.
They marked one side of a dolphin with an ‘X’ and didn’t mark another before letting them swim around. The dolphin that was marked swam straight up to the mirror and turned to look and see what had been drawn on it while the other dolphin didn’t show any interest. Other animals have taken the same test and the elephant and primates both are able to pass this test as well.
It’s important for humans to remember that we are not alone on this planet and that other highly intelligent creatures are dependent on humans treating their environments with care. We must work together to create a world where all creatures are respected.
16. Dolphins Have Great Social Skills and Create Strong Bonds
Dolphins typically only have one calf that stays with them for the first seven years of their life. This kind of long-term family bond is rare in animal species.
Some of the only animals that stay with their babies longer than this is elephants, who live with their family until they are at least nine years old and tamarins, a type of South American primate, that live in groups for life.
Dolphins love to swim in groups and can be found in pods of as many as a thousand different dolphins. This kind of organization is rare. To maintain their society, dolphins have very social and helpful behaviors.
If a dolphin is injured, the other dolphins will work together to help it get to the surface every thirty minutes to breathe. They have also been known to help other animals and even humans when they are in need.
17. The Largest Species of Dolphin Is the Orca
The Orca, also known as the “killer whale”, is actually a dolphin. The name references that it kills whales, not that it is a whale that kills.
Known for their distinctive coloring of black and white, orcas grow up to six tons – that’s twelve thousand pounds or around the size of a bus. They are between twenty-three and thirty-two feet in length.
As a marine carnivore, they love to feast on seals, sea lions, and whales with their teeth that can be up to four inches long. When they can’t find their ideal prey, they will settle for fish, squid, and seabirds.
While orcas prefer cold, coastal waters, they can be found anywhere between the polar regions and the equator.
They live in pods of about forty and can be both residential or transient. The residential orcas prefer fish while the transient ones are more likely to go after larger prey.
18. Dolphins Have More Brain Capacity Than Humans
When learning about dolphins, many people begin to ask themselves whether they might be as smart as humans. Their brains weigh 1600 grams to our 1300 grams.
Not only are dolphin brains large, but they also have a complex neocortex, which is the part of the brain that allows you to be self-aware and solve problems.
In addition, researchers have located gangly neurons in dolphin minds, which are the neurons that are responsible for emotions social cognition, and the ability to know what someone else is thinking.
Beyond being able to recognize themselves in a mirror, as mentioned before, dolphins also demonstrate their intelligence by being able to understand gestures that are highly complex from their human trainers.
They learn about their environments much the way small children do and can be taught to press a keyboard to release a toy to play with.
19. Dolphins Use Tools
Over the course of evolution, hunters and gathers turned to tools to better be able to find food and perform work without having to use up all of their time and energy. At the same time as humans were evolving, dolphins were as well in their own way.
Dolphins also use tools. They have been observed picking up sponges to protect their snouts while they forage for food at the bottom of the water. While scientists are still discovering all of the ways dolphins interact with tools, it’s clear they use them for lots of different porpoises.
20. Every Dolphin Has a Signature Whistle so Others Can Recognize It
Just like how humans have names so that they can recognize who they are talking to, every dolphin has a distinct whistle that signals their presence to other dolphins.
In addition to this whistle, dolphins also make tons of other sounds. Scientists are studying their language using algorithms and long-term recording devices to try to make out a pattern and decode what the dolphins are saying. Perhaps one day we will uncover some sort of “Rosetta Stone” that helps us understand the world below the sea in a whole new way.
Should Dolphins Be in Captivity?
Now that you have a better understanding of how intelligent dolphins are and how complex their lives can be, it makes you think twice about keeping them confined to captivity.
The area allocated to dolphins in a zoo is one-ten-thousandth of one percent of their territory that they have access to in the wild.
Philosophers debate on what makes a being sentient and it’s believed that dolphins have most of the necessary requirements. They are self-aware, have personalities, act ethically, are aware of their environments, and have complex emotions.
Knowing just how close to human dolphins are should make you want to fight to protect their habitats and keep them out of captivity.
Plan Your Dolphin Watching Trip to Florida
Now that you have all of these fascinating dolphin facts, you should consider taking a dolphin watching tour. Southwest Florida is an excellent place to see dolphins in their natural habitat.
We offer dolphin watching tours and almost 100% of the time, we are successful in seeing local pods of dolphins. Years of experience have perfected the art of locating dolphins.
The best part is that our dolphin tours include our shelling tours, so not only can you see dolphins splashing and playing in the Gulf, you can find beautiful shells on Shell Island, Marco Island, and Naples.
Contact us today to book your tour by calling (239) 301-8914!
