The Sea of Cortez in La Paz, Mexico is home to one-third of the world's dolphin population due to its abundance of smaller sea creatures, such as squid, crabs and fish that dolphin feed on. Renowned for their playfulness, intelligence and affection towards humans and each other, dolphins can't help but amuse snorkelers and divers with their seemingly smiling faces. There's no denying dolphins are almost magical creatures, complete with their own special language and gregarious personalities.
The sleek, gray bodies of bottlenose dolphins have a dorsal fin on their backs and two side fins to allow for rapid swimming and make them one of the most easily recognizable of all marine creatures. As well, they feature a long, beak-shaped nose for which they are named. Their real nose, however, is the blowhole on the top of their heads. Full-grown adults range anywhere from 2 to 4 meters long and weigh from 150-650 kilograms. Typically, 20% of their bodyweight is blubber to help keep dolphins warm underwater.
Living in small groups called pods, bottlenose dolphins are rarely alone in the Sea of Cortez. It is not uncommon for smaller pods to join other pods to form a large group; however, these groups are continually changing. Dolphins are natural predators and do occasionally behave aggressively. This is generally illustrated by head-butting and fighting amongst each other for rank, as well as showing aggression toward certain sharks and smaller species of dolphin. Overall, dolphins are extremely friendly creatures and have even earned the nickname "Man's best friend of the sea." There are several noted cases of dolphins rescuing injured divers by raising them to the surface of the sea.
Romance and courtship are huge factors in dolphin reproduction. Courtship practices involve males playing, nuzzling, yelping and posing for the female in order to gain consideration. Gestation lasts about a year, and the single calf is born in shallow water with the aide of a "midwife," or helper dolphin. Calves are nursed for up to a year and a half and stick very closely to their mother for the first 6 years. Dolphins are famously attached to their young and have very nurturing, almost human-like maternal instincts. Mothers typically care for their young alone; males are not involved.
Flipper, the beloved "rescue" dolphin, was featured on a long-running TV sitcom and was often helping families in need and protecting their human friends. This series sparked the notion that humans and dolphins could communicate with one another. Scientists have more than enough evidence that dolphins absolutely do have their own language. These mammals make a series of clicks, buzzes, squeaks or screeches that serve two distinct purposes: navigation and communication. Of all the animal species, only humans and dolphins possess a language so complex. To communicate with each other, dolphins generate high-pitched whistles and clicks to express alarm or sexual excitement. As well, dolphins are natural mimics and are often found imitating sounds made by their trainers.
To navigate their way underwater, find food or judge distances, dolphins use their echolocation navigation system. Simply, this means they produce a series of high-pitched sounds and are thus able to navigate by the way their sound "bounces" off an object. A dolphin can then evaluate how close or far they are from an object, and how big or small that object is. In one scientific test, a dolphin was able to locate an object approximately the size of a marble in an area the size of a football field.
As their nose lies in their blowhole which stays closed underwater, bottlenose dolphins have a very weak sense of smell. Their sharp eyesight, however, accompanies their amazing sonar ability so dolphins are able to see even in dim light, such as underwater. Dolphins' pupils perfectly adapt and allow them to easily find their way through the Sea of Cortez.
Zoos and theme parks often have dolphin entertainment as a major draw. Because of their intelligent, clever nature, dolphins easily learn to follow directions and enjoy the awe and applause they gain from delighted crowds. Dolphins in La Paz, Mexico are very similar; although there is no trainer, they are often found swimming in the water near scuba divers and snorkelers and love following the waves created by boats, much to the amusement of the lucky swimmers and boaters.