Dolphin’s are playful, affectionate, curious, intelligent, social, vocal and enjoy sex — especially after a big meal. Are they the creatures humans would have been had we not left the water?
Dolphin’s are aquatic, top-predator, mammals classified as a type of whale or cetacean. There are two types of cetaceans. Balean whales filter massive amounts of small oceanic organisms like krill with comb-like sieves in their mouths. Toothed whales, on the other hand, grab prey with their teeth. Dolphins and their mistaken twin, the porpoise, are a type of toothed whale. There are about 70 kinds of toothed whales of which there are about 45 species of dolphins, porpoises and false whales, like killer whales or orcas.
Dolphins are miraculously adapted to murky rivers, as in the Amazon River dolphin or boto, shallow coasts like Hector’s dolphins of New Zealand, or in groups of 10,000 bottlenose dolphins roaming the open oceans.
Like humans, dolphins are exceptionally tactile creatures and their skin conveys different levels of information or signals to each animal. Excellent sight enables them to see in the dark. Dolphin’s range of hearing is 10 times that of humans. Each animal has its own signature whistle, which is used to keep in contact with other individuals. Adult dolphins discipline their misbehaved juveniles by driving them to the ocean floor and momentarily holding them there.
So what makes the dolphin such an effective top-level predator? It’s their marvelous combination of intelligence, made-to-order radar system, adaptable hunting techniques and intensely powerful bursts of speed.
Dolphins are innovative when faced with a new, never-encountered circumstance. This goes beyond genetic programming of behavior. Innovation allows rapid assessment of a new situation and reactions to it. Dolphins clearly understand gestures similar to sign language that chimpanzees are also able to learn. Humans and dolphins appear to be the only known animals to spontaneously interpret images on a screen without prior teaching. Dolphins are capable of highly flexible behavior and therefore are considered intelligent.
Dolphins constantly send out noises called “click trains” which sound, to the untrained ear, like old creaky doors. These complex series of sounds are the most sophisticated advanced forms of sonar, called echolocation, unrivaled by anything on the planet — man-made or otherwise. As the sonar waves move through water they encounter objects, bouncing back shapes and contents to be deciphered by the dolphin’s large brain (which is bigger than a human). Sometimes the sonar is so potent it actually stuns its prey.
Dolphins are able to quickly shift their food gather techniques by either hunting alone or in larger groups that herds shoals or bait balls of schooling fish. Killer whales, the largest of the dolphins, teach their young how to hunt sea lions, seals and porpoises by herding and then isolating them.
Most fish tend to move sideways like the sinuous movement of a snake. Dolphins and other whales move up and down as their strong bodies flex like a bounding deer. Incredible strength comes from their tail or fluke that is horizontal rather than vertical.
How is it possible for dolphins to sleep as much as one third of each day when their predators are always hunting them? They usually rest in groups that bunch tightly together. One lazy eye per dolphin remains open and, although asleep, slow methodical echolocatory clicks scan their environment for sharks and killer whales. The group essentially forms a sensory integration system, each relying on the others sonar system to detect any trouble whilst they rest.
Scientists have been able to listen to cetaceans with special underwater sound equipment called hydrophones. And the renowned OrcaLab on Hanson Island in British Columbia’s Johnstone Strait has been studying intelligence 24/7 for the past 20 years. They record and track many pods off the west coast of Vancouver Island and know each killer whale by its signature whistle. These complex exquisite creatures share common fishing grounds, belly rubbing rituals on shallow pebble beaches, escort other pods through the strait and gather with an intricate timeless symphony of indecipherable dialects that plays underwater along the southwest coast of British Columbia.
Over fishing, marine and agricultural pollution and plastic bags clogging intestines have all taken a deadly toll on dolphins. Still today some countries allow the use of 40 miles-long drift nets that senselessly kill all life in its wake including cetaceans. As informed consumers its incumbent upon us to only buy “dolphin-safe” tuna, and use organic cotton shopping bags instead of disposable plastic bags.
For at the end of the day, wild dolphins, like all other animals on Earth, including humans, are just trying to make a living and survive.
Dr. Reese Halter is an L.A.-based public speaker and founder of the international conservation institute Global Forest Science. He can be reached through www.DrReese.com.