Dolphins are perhaps one of the best loved, and most fascinating of all Mammals. Part of the Cetacean order, and Whale family, they inhabit many of the worlds oceans, along with some coastal areas and rivers too. Dolphins have long been scientifically classified using well thought out, and ordered methods, but the common names of some species can lead to confusion. Some species have ‘Whale’ in their name, and while part of the larger Whale Family, are in fact a ‘species’ of Dolphin.
This article will cover some of the common and most recognisable species of Dolphin, while also taking a look at others that inhabit coastal, oceanic, or tropical waters, and examining the Dolphins close relation, the Porpoise. Each have their own distinctive features, behaviours, and diets, although one thing they all have in common, is the use of Echolocation to locate prey and avoid danger in the waters they inhabit.
The Killer Whale
One of the most famous (thanks to the film Free Willy), distinctive, and powerful Ocean Dolphins in the world, is the Killer Whale or Orca. As one of the giants in the Dolphin world, their diet contains somewhat larger prey than many of their cousins, as they enjoy feasting on seals, sea lions, and large fish. These mammals are distinctive for their black and white colouring, for hunting in so called ‘deadly’ pods, and for being protective of their young. Commonly found in cold, coastal waters.
There are two main sub-species of Common Dolphin, the Short Beaked, and Long Beaked Dolphin. Although found in many of the world’s tropical waters, the Short Beaked variety is found offshore, while the Long Beaked prefers coastal waters. They are known for the colourful crisscross pattern on their skin, being fast movers, and relishing a diet of schooling fish and squid.
This is one of the best known, best loved, and most intelligent and playful of all the species of Dolphin. This species is commonly seen on films and television, and also a feature of many Dolphin watching trips, research, and entertainment in Marine parks. Grey in colour, they can grow up to 12 feet long, with a curved dorsal fin, and hunt both individually or as a pod. They are found worldwide in warmer waters, and have been sighted close to shore in harbours and river mouths. There has been much talk of the hunting of Bottlenose Dolphins, particularly in Russia and Turkey in the past, and there were also problems with Dolphins being trapped in fishing lines, leading to the introduction of ‘Dolphin Friendly Tuna’ on shop shelves across the world.
The Spinner Dolphins, so named for the striking way they burst out of the water and spin in the air, were first recorded by a Benedictine Monk called Dom Antoine-Joseph Pernety in 1769. There are two species of Spinner Dolphin, The Long Snouted, and Short Snouted, and while both have small fins, and grey/white colouring, their exact size, colour, and features will vary depending on their location. Spinner Dolphins are also known for having more teeth than all other Dolphin species, and travelling in massive herds of over a thousand animals. The places they have been sighted include the coast of Mexico, and the western cost of Central America.
In terms of appearance, the Spotted Dolphins are one of the most striking in the Dolphin family. Their spots tend to reflect the light, and make an interesting sight for any diver swimming with them. They may be distinct, but they are also hard to describe, with their colouring and number of spots varying depending on where they are found. There are two main sub-species here, the Pan Tropical Spotted Dolphin found across the world, and the Atlantic Spotted Dolphin. These Dolphins are known for being highly social, though they like to swim with Tuna, which has led to trouble in the fishing industry.
There are five main species of River Dolphin in existence, which are commonly found in Asia and South America, and named after the rivers they are sighted in. The Amazon River Dolphin is the largest of this sub-species, and with the Ganges River Dolphin, Indus River Dolphin, and Yangtze River Dolphin inhabit freshwater rivers and estuaries, while the La Plata Dolphin is a saltwater mammal. This species of Dolphin is sometimes confused with its close relation, the Tucuxi.
One species, the Amazon River Dolphin, has been the subject of myths, with Amazon Folklore reporting that by night the Dolphins become handsome men, and impregnate women. This may be a myth, but what is rooted in fact, is that these white, pink, yellow, brown, grey, or black creatures, exist in naturally low numbers, suffer from habit loss, and could one day become extinct.
The porpoise holds the record for being the smallest of the toothed Whales. Although they look very much like their cousins the Dolphins, there are some differences, predominately that they have thicker bodies, a blunt muzzle, and some have no dorsal fin. There are around six species of Porpoise, including the common Harbour Porpoise, found off the Atlantic and Pacific coast in America, and the Pacific based Dall’s Porpoise. Other species that have been named and recorded are the Burmeisters Porpoise, The Finless Porpoise, and the Spectacled Porpoise.
Last but by no means least, is the Narwhal, one of the most unusual of the Dolphin species. Nicknamed the ‘Unicorn’ thanks to its prominent tusk, one of two teeth the male Narwhal possesses. This distinctive feature can grow up to 8 feet long, and has been hunted, along with the animals vitamin C enriched skin in the arctic waters it inhabits.
The list above is by no means exhaustive, and there are many other species and sub species of Dolphin that have been identified and classified in our rivers and oceans. These include the little known Black Dolphin found in Chile, the Commerson’s Dolphin with its black and white markings, found off the South American coastline, the Indo Pacific Humpbacked Dolphin and Atlantic Humpbacked Dolphin. There’s also the Frasers Dolphin, Southern and Northern Right Whale Dolphin, the Rough toothed Dolphin, Hourglass Dolphin, and the False Killer Whale. All these species, along with others mentioned in this article, have their own unique features and characteristics, whether it’s the number of their teeth, their diet, colourings, length of beak, or hunting patterns. This is part of what makes Dolphins and their close cousins, a fascinating part of our marine environment, for experts and animal lovers alike.