Delving into the World of Dolphins
10 Amazing Things You Didn't Know About Dolphins
How often do you drive over one of the many Lowcountry bridges and scan the water to see if you can spot a dolphin or two? There is something about these magnificent creatures that intrigue us. Maybe it's their seemingly jovial spirit that draws us in, or their willingness to get so close to us. Dolphins and humans have long had a history of interaction, dating back to ancient times. These animals arguably have the closest similarities to human intellectual and social patterns. Our beautiful coastal waters abound with dolphins and we should consider ourselves lucky to spot them, as many cultures acknowledge their appearances as an omen of good things to come. Dolphins are thought of as playful, with a friendly and calm disposition. This is true; however they are still wild animals and can be
unpredictable and aggressive.
Here are ten amazing things you probably didn't know about dolphins that will make you fall in love with them all over again, but that should also make us more cautious and respectful of our coastal neighbors.
- They use tools: Dolphins will place ocean sponges on their rostrums (snouts) to dig in the muck, protecting them from stingrays and sea anemones when they bottom feed. The development of tools is a great indication of their high intelligence.1
- Dolphins live and travel in social groups called pods: Being a matriarchal society, females usually make up the population and can include three generations. Females care for other, younger animals in the group, becoming 'aunties,' which help them learn parenting and nursing skills before they give birth themselves. They have social hierarchies and a complex social structure. Males usually pair up with unrelated males early in life and form bonds that last their whole lives.1
- Range of feelings: Dolphins can show signs of affection, anger, frustration and sadness. They are far more aggressive than people think and enjoy rough housing. They leave scratch marks from their teeth on the sides of other dolphins and often resort to physical intimidation to control young or new animals.1
- They call each other by name: Female dolphins have a specific call for each calf. Dolphins carry each calf for about one year before giving birth. After birth they will nurse up to about three years of age. Individual identity is both a dolphin and human trait. They are also some of the most vocal animals. They can use body language and at least 30 different sounds. Dolphins can also change the meanings of sounds by adding different postures.2 & 3
- Dolphins use Eco location: They are able to produce clicking sounds that bounce off objects. Echoes of these sounds come back to the dolphins and enable them to make out images of the object being investigated. They can use this to find objects under the sand, or even if it is pitch black, form detailed images of objects around them. Pretty impressive! Eco location capabilities are superior to anything man can create and the navy is currently studying this.1 & 2
- Dolphins have interesting bodies: Dolphin skin has a special quality that flows under water pressure, increasing speed. They can also collapse their rib cage to push air out of their lungs, which keeps them from getting the bends. Dolphins do not drink salt water. They get their water from the fish they eat. They can also tan in the sun making them darker in the summer, lighter in the winter.1 & 2
- Dolphins don't sleep: Dolphins rest half of their brain at a time. They do not sleep like we do. This helps them to stay aware of any predators. Also, unlike people, dolphins have to think about each breath they take. If they were to go to sleep like we do, they would not breathe.2
- They are mammals: Dolphins share five major characteristics with humans: hair at some point (whiskers on rostrum of newborns), nursing their young, giving live birth, being warm blooded and breathing air. Even though dolphins have lungs-not gills-they can hold their breath for eight to ten minutes, although they usually breathe more frequently.2
- A dolphin brain has six layers-so does a human brain, but they have 50% more cortex cells than the humans. They have very good memories, remembering signals for behaviors years after not doing the behavior. They think quickly and can get bored by simple tasks. They like to be challenged. Their memory capacity is equal to humans.
- Dolphins can recognize themselves in a mirror: Lou Herman has done studies in Hawaii on language and self-recognition with mirrors over the years. Dolphins, along with apes and humans, are the only known species that are aware of their own images and recognize themselves. 1
"Dolphins' capability to be trained shows a real intelligence. Our three-year-old dolphin never ceases to amaze me with his intelligence and ability to learn. A lot of his behaviors we didn't even have to train. He just learned them on his own by watching and mimicking other dolphins," stated Adrienne Baldwin, a marine mammal trainer at Sea Life Park in Hawaii. Dolphins and humans have many similar characteristics, intelligence being among the top of the list. Intelligence gives way to curiosity and dolphins take the opportunity to see if they can use a situation to their advantage. The experiences and interactions that most humans have with dolphins "are really only because they are curious and looking out for their own interests. They are alert to their environment and to what is happening around them," explained Nedra Hecker, retired marine mammal trainer. "We mistake this interest for playfulness."
It's true that dolphins are fascinating animals, loved and revered by millions, but there is more to them then what Hollywood portrays. For starters, they are extremely important to our environment. "They are one of a number of indicator species-any biological species that defines a trait or characteristic of the environment. Since they are a top component of their environment, it is important to study them to see if they are having problems because of man-made effects in the ocean or a loss of population numbers due to humans overfishing and the dolphins not getting enough prey items." Nedra explains. "Dolphins are protected in USA waters, by the Marine Mammal Protection Act and we need to make sure their environments remain healthy and they are not irreparably harmed by our pollution, boating, and recreational activities."
Fun Fact: Dolphin v. Porpoise:
In the USA dolphins are often mistakenly called porpoises. The only true porpoises found in the USA are Harbor Porpoises, found only in the colder waters up above Cape Cod. Dolphins have 88 cone shaped teeth, a defined beak, a pronounced forehead, and a curved dorsal fin. Porpoises are smaller, have flat, chisel like teeth, a round head and more of a triangle shaped dorsal fin.
Interesting Local Fact:
Spotted often by locals, beloved Snowball was a female albino dolphin that was captured in St. Helena Sound off the coast of Beaufort in 1962 and taken to the Miami Seaquarium, where she lived until she died in 1965. Her capture was the main catalyst in the creation of a statewide ban on the capture and removal of marine mammals in South Carolina called the Marine Mammal Protection Law, signed Oct. 21, 1972. (http://www.nmfs.noaa.gov/pr/laws/)