Unlike fish that have gills and can breathe underwater dolphins require air to breathe and must come to the surface of the water when they need oxygen.
When you combine all three types of marine mammals there are over 85 different species of cetacean.
When it comes to the dolphin species there are currently around 40 different species of dolphin that live in the ocean today.
Dolphins are extremely intelligent and playful animals.
They are also one of the most acrobatic species known inhibit the sea.
In fact dolphins are able to dive up to 1000 feet under the ocean, jump over 25 feet high and swim faster than 30 miles per hour.
Depending on the species of dolphin and where they are located their diets can vary significantly.
Note: The killer whale and false killer whale are both dolphins, not whales.
In terms of size dolphins vary greatly from Maui’s dolphin which measures in at around 4 feet and weighs about 90 – 110 pounds to the killer whale which can grow to 30 or more and weigh as much as 22, 000 pounds.
Most species of dolphin have slim streamlined bodies that are created to give them great speed and agility and a few species have rounder and more stocky bodies.
In order to swim and pick up speed dolphins use their tail for propulsion and their fins for stabilization which helps them turn, roll and navigate through the water.
Unlike some whale species that have two blowholes, dolphins are born with a single blowhole.
Also unlike some whales species most dolphins make small migration trips or stick to a single area all year long rather than taking large journeys to new destinations.
When dolphins do migrate it is usually to follow their food source since it is a vital component of their survival.
Dolphins typically prefer tropical climates, however some species such as the killer whale may be found living in colder climates as well.
Most species belong to one of two ecosystems.
Coastal dolphins prefer to stay near the coast in shallow waters, which is where the majority of dolphins appear to be.
Off shore dolphins are typically larger than coastal dolphins and prefer to live further out in the ocean.
Because coastal dolphins live in and around the coast line they are often limited in their range of travel so they end up staying in or near the safer coastal waters where they are less likely to be threatened by larger marine mammals and other threats found in the ocean.
On the down side these dolphins are also more likely to suffer from water pollution, fishing hazards such as getting caught in fishing nets and being struck by large boats.
Offshore dolphins are larger and do not live near the coast line so they are more likely to migrate during seasonal changes and/or when their food supply migrates.
As a species dolphins are extremely intelligent and social creatures often traveling together in groups of 2 - 30 dolphins.
In some cases such as during feeding periods or social activities dolphin groups may be much larger containing several hundred dolphins at a time.
In addition to gathering together for social events dolphins also form large pods or groups as way to protect themselves against predators.
Dolphins communicate with one another by creating a series of clicking and whistling sounds.
They also use various body language signs such as leaping out of the water, slapping their fins against the water and bumping into one another.
These sounds and signs allow dolphins to communicate affection, alert other dolphins of nearby danger and inform others of food they have found among other things.
Interestingly each dolphin has a slightly different frequency when it communicates.
This allows other dolphins in the area to distinguish which one in the groups is communicating.
These sounds can also be used to help a dolphin find other dolphins that belong to its pod or help a mother keep track of her children.
In addition to communicating with one another through sound dolphins use echolocation to help them track prey and navigate the ocean, which is especially useful during times when visibility is low such as at night-time or during deep dives.
When it comes to giving birth the average gestation period for a female dolphin is 11 – 17 months depending on the species.
Female dolphins typically produce offspring every 2 – 6 years and will raise their young for several years after they are born.
Female dolphins usually mature between the ages of 5 - 13 while males usually mature between the ages of 6 – 14, although some species may mature at later ages.
Unlike certain whale species that have a feeding season and mating season dolphins can bare offspring all year-long, however dolphins are more likely to mate during the warmer months.
During mating periods adult male dolphins can become aggressive and competitive sometimes fighting with other males or herding off the female to limit her chances of becoming impregnated by other males.
Some males dolphins will even create factions fighting and fending off other factions trying to mate with their females.
10 Awesome dolphin facts for kids
1) The largest known dolphin is the killer whale (yes the killer whale is a dolphin) which is able to grow to lengths of over 30 ft. long.
2) All species of dolphin are capable of using echolocation to hunt for food and navigate the ocean in completely dark environments.
3) Sound travels 4 times faster in water than it does on land and dolphins have an excellent sense of hearing allowing them to maintain awareness of their environment and react quickly when necessary.
4) Although dolphins have teeth not all species use their teeth when hunting for food and some dolphins swallow their prey whole.
5) Depending on the species some dolphins can be found traveling in all of the worlds major oceans from the tropical environments near the equator to the polar regions around the northern and southern polar hemispheres.
6) Some species of dolphin are known to hold their breath for over 15 minutes when searching for food.
7) The fastest dolphins can reach speeds of over 30 miles per hour for short bursts when frightened or trying to capture prey.
8) The personalities of dolphins can vary just as much as a humans and although dolphins are known for being extremely social and acrobatic there are several species that are more reserved and prefer to remain distant and undetected.
9) Dolphins are so intelligent that some species have been used in the military to find underwater mines and look for passengers lost at sea.
10) Some dolphins have unfused necks allowing them to turn their head a full 90 degrees so they can maintain constant awareness of their environment.