- Education and Science»
- Life Sciences»
- Marine Biology»
- Marine Life
Dolphins or Porpoises?
Since coming to Naples, Florida, I have marveled at the nature around me. It is so abundant and beautiful and I never tire of watching it - it truly is so entertaining. As I've mentioned before, the beach and the Gulf of Mexico are two of my favorite places, and the day I discovered dolphins playing in the Gulf and entertaining us on the beach with their jumps and flips, I was totally smitten. I love dolphins and they seem to love us. They are the most delightful, beautiful,and athletic beings in the Gulf. I watch for them every time I go to the beach, and they never fail to show up, amaze me, and entertain me.
But, I also got to thinking exactly what are the differences between dolphins and porpoises? Although I was loving watching these dolphins, was I ever watching porpoises and didn't realize it? Everyone on the beach claimed they were dolphins. Okay, then what are porpoises, and how do I tell the difference? So, I've done some research and I'll share with you what I have learned.
Dolphins are marine mammals who are closely related to porpoises and whales. Dophins specifically belong to the Delphinidae family and are the largest in the cetasean order. Found in the shallow seas of the continental shelves, dolphins are carnivores and they eat mostly fish and squid. They are one of the most intelligent of animals with a friendly countenance and playful attitude as evidenced in the Gulf. This is what has made them so popular with humans
The long, sleek. streamlined, fusiform body of the dolphin is adapted for fast swimming. The fluke, or tail fin, is used propel them in the water. The pectoral fins along with the tail are for directional control. The dorial fin gives stability to the dolphin while swimming. The head of the dolphin contains a melon which is a round organ used for echolocation. Echolocation is a form of sonar hearing and communicating that the intelligent dolphin uses. Dolphins also breathe through the blowhole on top of the head, and their brains are large and highly complex.
Dolphins have very acute eyesight, both in and out of the water. They can hear frequencies ten times or more above adult hearing. Surprisingly, most of their hearing is down with the lower jaw. It conducts sound to the middle ear via a fat-filled cavity in the lower jawbone. The dolphins' teeth act as an antennae to receive incoming sound and they can pinpoint the exact location of an object. This is how they find food to eat and navigate under water in which they are submerged most of the time.
Very active in their social life, dolphins live in pods or schools of up to a dozen individual dolphins. They can temporarily merge into superpods of a thousand or more at a time. They can establish strong social bonds with themselves, other fish, and human beings. They will stay with an ill dolphin by bringing them to surface for air if needed. They have been known to protect human swimmers from sharks by swimming circles around the swimmers. They will even charge sharks to shooo them away from swimmers.
Their unique language has fascinate scientists for years. Dolphins are capable of a broad range of sounds:
- frequency - modulated whistles
- burst-pulsed sounds
- clicks which are directional and for echolocation
Are they talking to us? Dolphins, being so intelligent, have been easily trained and can be counted on to help human beings. They adapt well to captivity and scientists and researchers have been able to test their language abilities and playful attitudes. Dolphins occasionally leap above the water surface and complete acrobatic twists and turns as they leap. Play is such an important part of the dolphin culture and they will playfully interact with swimmers. They are not afraid to come close to us swimming in the Gulf. When in the water I have never felt intimidated or afraid of dolphins. They enjoy riding the waves and will jump over me when lying on my "floatie" on the gulf. They are playful and entertaining and I always feel safe around them.
Porpoises resemble dolphins in looks and both share some similaries but there are distinct differences between the two. Porpoises belong to the Phocoenidae Family and are related to dolphins and whales. But they are distinct in looks from dolphins. They are smaller and stouter than dolphins. With small rounded heads and blunt jaws instead of beaks, they have a distinctive different look from dolphins. Porpoises teeth are spade shaped, while dolphins have conical teeth. Their dorsal fin is triangular rather than curved as in the dolphin.
Porpoises live in all oceans, but not in the seas, and live mostly near shore. There are freshwater porpoises also called finless porpoises. The best known of all the porpoises are the harbor porpoises found across the northern hemisphere.
Like dolphins, porpoises are carnivores and find food and communicate with each other through using sounds and echolocution in sonar form. Fossil evidence has shown scientists and researchers that porpoises diverged from dolphins and other cetaceans. Most porpoises are found in the shallow oceans around the north Pacific and spread to the European coasts and the southern hemisphere.
The small size of porpoises means they lose body heat to the water more rapidly than do dolphins. Their stout shape may be an adaption to reduce the heat loss. Their thick blubber also insulates them from the cold. This requires them too eat more frequently than dolphins rather than depending on their fat reserves. They bear their young more quickly than dolphins, producing a single calf each year. Pregnancies last eleven months. The average life span of a porpoise is eight to ten years.
Porpoises are also found together most commoly in small groups of fewer than ten individual porpoises called pods. They are very fast swimmers and can attain speeds of 34 mph or more. They are far less acrobatic and more wary of other fish and human beings than dolphins. Therefore, they are rarely held in captivity in zoos or aquariums as they are not as capable of adapting to tank life or as easily trained as dolphins.
So, I have to admit, I'm glad it is dolphins that inhabit the Gulf of Mexico. I see them every time I visit the beach and Gulf, and look forward to them as friends of the sea. I can't help wondering though, what do they think of us?
Dolphin Tale - The Movie
I highly recommend that everyone see the film, Dolphin Tale, a true story that takes place in Clearwater, Florida. It is an excellent film for all ages, and you will be inspired by Winter, a female dolphin and her journey to recover from an amputated tail. The movie can be enjoyed on every level. It is a true feel good movie and the main theme is that anyone with any type of disability can learn from and be inspired by this disabled dolphin, Winter, and her "tale." It is also the story of what alternative education can do to engage a young boy in learning.
But, the greatest theme is that we are all "family forever." It doesn't matter what shape we are in, whether we can walk or not, whether we have been severely injured --- we are all in this together --- and we are also in this with the animal life here on earth. We are "family forever" with Winter, the injured dolphin, and we have to look after one another and take care of one another.
We also see evidence of dolphin intelligence as Winter "talks" and communicates with the boy who found her and cut her free from a fishing trap. Winter actually recognizes him by sight and definitively knows who her rescuer is. She is playful with him and literally pulls her friend into the pool to swim and play with him.
This is a feel good movie that everyone will enjoy and at the same time meet a new friend in Winter, the injured dolphin, who receives a new tail in the end!
You can see and meet Winter at the Clearwater Aquarium in Clearwater, Florida or meet Winter on her web site --- http://www.seewinter.com.
- Marine Life - Ocean Animals, Plants and Habitats
Explore the world of marine life, including ocean animals and plants, through images and species profiles of marine vertebrates, invertebrates and plants, including whales, dolphins, porpoises, seals, sharks, sea turtles, fish, shellfish, and more. F
- The Marine Mammal Center : Home
- Dolphin World–(800)667-5524-You can swim with dolphins in Florida, Hawaii, Caribbean, and Mexico
From $79 - Dolphin World is your swim with dolphins place. You can do this incredible experience of swimming with the dolphin in Florida or Hawaii or Mexico or the Caribbean. Find out where to swim with dolphins from this website.
- ACS - American Cetacean Society
The American Cetacean Society; whale and dolphin conservation, education, and research from the oldest cetacean conservation group in the world.