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Dolphins of the World. DOLPHINS OF THE WORLD. Introduction : All dolphins belong to the cetacean family. This order includes whales, dolphins, and porpoises.
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DOLPHINS OF THE WORLD • Introduction: • All dolphins belong to the cetacean family. This order includes whales, dolphins, and porpoises. • There is some debate over how many different species of dolphins there really are. Some say there are 32 different species, while others 33. It all depends on whether the White Whale is considered a dolphin. • Points of interest: • Dolphins sleep only with one half of their brain at a time! Remember Dolphins are conscious breathers. Should they sleep and go unconscious as we do they would simply suffocate or drown. Sleeping Dolphins can be seen as resting, floating at the surface, with one eye open.After a time, they will close the one eye and open the other one. • Cetaceans can taste, but have no sense of smell. • Only 5 specific species live in fresh water.
Dolphin Facts: • 1. Dolphins are mammals. As all mammals, dolphins nurse their young from mammary glands. • 2. Dolphins can swim up to 260 m. below the surface of the ocean. However they are mainly shallow divers as they need to reach the surface to breathe. • 3. Dolphins can stay up to 15 minutes under water. • 4. Dolphins use a technique called echolocation. This technique uses the same principles of a radar, and it is used to find food and navigate. 5. Dolphins are social beings. Dolphins live in groups and cooperate among each other for activities like getting food and calf-raising.
7. The largest dolphin is the Orca, also known as “killer whale”. Orcas grow up to 6.1 meters long and belong to the toothed cetacean family just like dolphins do. • 8. The most popular dolphin is the “bottlenose dolphin". Bottlenose dolphins are the ones we have seen on television, movies and aquatic shows. Bottlenose dolphins can grow up to 2.8 meters. • 9. Dolphins communicate by making a unique signature whistle that may help individual dolphins recognize each other, collaborate and perform several other kinds of communication. • 10. The fastest dolphins can reach up to 32 km/h.
Haeviside's Dolphin • Heaviside's dolphins are a small, short-beaked dolphin found only off the southwest coast of Africa • Heaviside's dolphins are about 1.7 meters (5 ft 7 in) long and have no pronounced beak. Their body shape is stocky rather than sleek, and they have blunt oar-shaped flippers. • The name Heaviside's dolphin came about because the UK surgeon and scientific collector, Captain Heaviside, was its discoverer.
Black Dolphin • The Black Dolphin is one of the smallest of all of the cetaceans. (4-6 feet - Weight: 65-145 lb ) • Other Names Used: White-Bellied Dolphin; Chilean Black Dolphin; Chilean Dolphin. • Black Dolphins are found along the coastal waters of Chile
Hector's Dolphin • The Hector's Dolphin is only found off the coast of New Zealand. • It is one of the rarest dolphins in the world. • It is also one of the smallest dolphins in the world – it can fit inside a bathtub. • There is a distinctive finger-like swoosh of white that extends from the belly, along the flanks towards the tail. The rest of the body is grey.
Commerson's Dolphin • This dolphin is also known as the Piebald Dolphin and the Skunk Dolphin (due to the similar coloring it has to a skunk). • This is one of the smaller types of dolphins. They only grow to be about 5 feet in length. They are quite round and don’t weigh more than 100 pounds. • Many people will tell you that they are the most beautiful dolphin. They are among the most active. They can do some amazing leaps very high out of the water and have been seen swimming upside down which is quite comical.
Bottlenose Dolphin • This robust dolphin has a short, stubby beak - hence the name "bottlenose". The bottlenose dolphin has more flexibility in its neck because 5 of the 7 neck vertebrae are not fused together as in the other oceanic dolphins. There are 18-26 pairs of sharp, conical teeth in each side of its jaw. • The color is generally light to slate gray on the upper part of the body shading to lighter sides and pale, pinkish gray on the belly. • It may weigh as much as 1,430 pounds (650 kg) • An adult may consume 15-30 pounds (8-15 kg) of food each day including fish, squid, and crustaceans.
Common Dolphin • Common dolphins are colorful and elaborate, with a complex crisscross or hourglass color pattern on the side • The back is dark gray-to-black from the top of the head to the tail dipping to a V on the sides below the dorsal fin. The flanks are light gray behind the dorsal fin and yellowish-tan forward of the dorsal fin, forming an hourglass pattern. • Its belly is white and there are large dark circles around the eyes connected by a dark line that runs across the head behind the beak and a black stripe runs from the jaw to the flippers.
The Northern Right Whale Dolphin • This species has a slender streamlined body with a short beak, sloping forehead, slim tailstock, and small flukes. They are the only species of dolphin without a dorsal fin found in the North Pacific Ocean. They are also recognized by a mostly shiny black coloration on the dorsal side and a contrasting less-visible white ventral side. • Northern right whale dolphins are capable of long leaps and bounces spanning more than 20 ft (7 m) over the surface of the water.
Spotted Dolphin • The upper body of the Atlantic spotted dolphin is a dark graycolor. They have a chunky beak with a spot of white on the end. The older the dolphin, the more spots. • The typical family group of the Atlantic spotted dolphin can consist of 50 individuals but is usually somewhere between 5 and 15. They are very vocal and active at the surface. • For reasons we don't yet understand, in the eastern tropical Pacific the spotted dolphin swims with yellowfin tuna. Millions of dolphins have been killed in the pursuit of tuna, with the spotted dolphin accounting for 80% of the casualties.
Southern Right Whale Dolphin • Southern right whale dolphins are the only dolphins without dorsal fins in the southern hemisphere. They are smaller than northern right whale dolphins and have more white on their head and sides. • They have slim, graceful bodies which are black on the upper side and white underneath. Their flippers are mainly white and are small and curved. Their flukes are small with a notch in the middle. Their beaks are small but distinct. They have between 43 to 49 teeth in each row of both jaws.
Spinner Dolphin • So called for their high, spinning leaps, spinner dolphins are known as playful, eager bow-riders. • They spend daylight hours at depths of up to 3,000 feet, but at night migrate towards the shore to hunt. Using their whistles, they call members of the school back together to unite in defence. • Over the next two hours the dolphins enter a resting state. • As the spinners awaken from their rest, some members begin to spin, urging the school to move out into the ocean. For the next hour or more, the spinners perform this zig-zag pattern. Finally they head offshore for another night of hunting.
Striped Dolphin • Striped dolphins have a unique look. They feature long strips of dark blue on their lighter colored blue bodies. They also have stripes of either pink or white on their belly. • The males and females are the same size - about 8 ½ feet in length. They average a weight of 350 pounds. • The striped dolphin will reproduce at about 12 years of age. In the wild they have a life span of about 60 years so there is plenty of time for mating to occur.
White-Beaked Dolphin • The white-beaked dolphin grows up to 3.1 meters (about 10 feet) and is sturdy and plump-looking. The body is mostly black or grey with a pale saddle behind the dorsal fin and white bands on the flanks. The belly is white and although called the white-beaked dolphin the beak is sometimes grey or even darker. • They are typically seen in groups of 5 to 50 and occasionally in schools of several hundred. They are attracted by boats and often bow ride. They are very acrobatic and have a distinctive “rooster tail splash” when swimming fast.
Clymene Dolphin • Clymene dolphins, sometimes known as the "short-snouted spinner dolphin," are relatively small in size. • They are a distinct species from the similar-looking "long-snouted spinner dolphin”. They appear physically similar to both striped and spinner dolphins. • These dolphins are recognized by a tricolored pattern on their sides that includes a dark gray cape, moderately gray flanks, and a white or pale gray underside. They also have distinct black lips that appear similar to a "moustache”.
Atlantic White-Sided Dolphin • The Atlantic White-sided Dolphin is named for its coloration. This species has a black dorsal region that fades to gray along its sides and a distinctive white coloration running along its ventral surface most of the length of its body. • Atlantic white-sided dolphins are capable of holding their breath for nearly 5 minutes.
Dusky Dolphin • The Dusky Dolphin is one of the most acrobatic of all dolphins. • It is known for its extraordinary high leaps and jumps. It is highly inquisitive and usually easy to approach. It also seems to enjoy contact with boats. They eagerly ride bow waves and may leap a dozen times in a row. Usually when one animal will start jumping, the others in the group will join in. • They are found in coastal temperate waters of New Zealand, Southern Africa, and South America.
Pacific White-Sided Dolphin • Pacific white-sided Dolphins are so named because of the white colouration on their sides and underneath. They are dark gray on top and have a pale gray streak along each side, starting above the eyes and then widening towards the tail. • They have small dark beaks and dark rings around their eyes. • Pacific white-sided dolphins are found throughout the temperate waters of the North Pacific Ocean from Japan to North America, and from the coasts of Alaska down to Baja, Mexico.
Peale’s Dolphin • Peale's dolphin is a small dolphin that inhabits the southern tip of South America. It has a small beak, and its coloration is a complex pattern of white, gray and black. They generally have a white belly, a gray area going from near the eye to the midpoint of the side, a black back and tail, and a white stripe on the flank. • It is sometimes mistaken for the dusky dolphin or the hourglass dolphin. • Peale's dolphins grow to as large as 7 feet and weigh up to 250 pounds. They feed on fish, molluscs, crustaceans, squid and octopus.
Hourglass Dolphin • Other names : skunk dolphin, Wilson's dolphin, and Southern White-sided dolphin. • It is most easily recognized by its unique white "hourglass" marking against a largely black body. Its underside is also white, though both sides of the fluke are black. The two white patches that make up the hourglass shape are often connected by points or at least a thin white line. • They feed on small fish, crustaceans, and squid. • Usually found in groups of 7-10, these dolphins are not at all shy when encountered and often bow ride, even approaching slower moving vessels. Sometimes they'll spin while riding the waves. When they bowride, they swim in long low leaps and may resemble a porpoising penguin.
Risso’s Dolphin • The Risso’s dolphin is one of the largest and most distinct dolphin in appearance. From a distance the distinct markings on their bodies may make it appear that a Risso’s dolphin has been involved in some type of battle. These markings will likely be more apparent as they get older. They are the result of battles with each other and with their prey over the course of their lives. • The coloring ranges from various shades of gray. The distinctive markings on them are white. • Another unique feature is that they have seven sets of teeth on their lower jaw but none on the top. They feature one dorsal fin and two flukes. They range in length from 10 feet to about 12 ½ feet. Males can weigh up to 1,100 pounds with females weighing much less at about 650 pounds.
Fraser’s Dolphin • The Fraser’s Dolphin is also well known as the Sarawak dolphin in some areas. This is a very large sized species that can be up to 8 ½ feet in length. However, they don’t weigh more than 200 to 300 pounds. The coloring of the Fraser’s dolphin ranges from dark gray, dark black, or dark blue. They don’t have a different color on their belly like most species of dolphins do. They also have a band of black around their eyes that is quite similar to that of the raccoon. • They are known to reside in the Atlantic, Pacific, and Indian Ocean areas. They have also been seen in the areas off the coast of France and Uruguay. The Gulf of Mexico is another common location for them.
Irrawaddy Dolphin • The species is found off the coast of South-East Asia, where in some areas it is severely threatened • It is identified by a bulging forehead, a short beak, and 12-19 teeth on each side of each jaw. The pectoral fin is broadly triangular. • When diving, this dolphin breathes at intervals of 70-150 seconds; the head appears first and then disappears, and then the back emerges, but the tail is rarely seen.
Rough-Toothed Dolphin • It is so-named because of the thin line of enamel that runs vertically along their teeth. They also have slender noses and conical shaped heads. Their flippers are set back on their bodies, which causes them to be confused with the Spinner, Spotted and Bottlenose Dolphins. • The flanks of the Rough-toothed Dolphins are a light grey color while the dorsal fins and backs are a darker gray. • The Rough-toothed Dolphins enjoy deep, offshore warm-temperate waters. They have been spotted near Hawaii, the Bahamas and Ogasawana, near Japan, and also off the Coast of Brazil. In the Eastern Pacific Ocean, the population is estimated around 150,000.
Pygmy Killer Whale • They are found around Japan, Hawaii and in the warmer eastern areas of the North Pacific Ocean It is also found in the West Indian area and around tropical western Africa in the Atlantic Ocean as well as in the Indian Ocean and the Gulf of Mexico. • They are very similar in appearance to the melon-headed whale and the false killer whale. The shape of the head, the dorsal fin and the flippers of pygmy killer whales are different from the other two. The head is rounded and lacks a beak. They have an underslung jaw and white lips, and usually a white patch on the tip of the lower jaw. There are usually 8-11 pairs of teeth in the upper jaw and 11-13 pairs of teeth in the lower jaw.
Melon-Headed Dolphin • They have a head that looks like a melon, with a very subtle beak. The head’s profile curves smoothly downward. They have 21-25 small slender teeth in each jaw. The body is dark grey to black in colour. There is a triangular "mask" on the face of these whales, as well as a cape that dips low below the dorsal fin. • The Melon-headed whale is seen along most of the African coast. • They are highly social, seen swimming in large groups of a few hundred and with other species, especially Fraser's dolphins. • Melon-headed whales feed on squid and small fish.
Indo-Pacific Humpbacked Dolphin • They are happiest in water temperatures between 15-36° Candare found in both the Indian and Pacific Oceans, from Northern Australia and Southern China to Indonesia to Southern Africa. The Humpbacked Dolphinsare also known to enter rivers, estuaries and mangroves. • They have a robust body, elongated hump on back, and a long slender beak. • It’s fatty hump begins to grow as it gets older. Those living west of Indonesia have very distinguishable humps; whereas those in the east have no humps. • They sometimes lie on their sides and wave their flippers.
Tucuxi Dolphin • The Tucuxi Dolphin resembles a small Bottlenose Dolphin. Both the Tucuxi and Bottlenose Dolphins are a light gray to bluish-grey in color on their backs, with a pinkish to light gray on the belly areas. The beaks of the Tucuxi is slender and long, similar to the Bottlenose Dolphins. • The Tucuxi has a freshwater and marine species.
Short-Finned Pilot Whale • Similar in appearance to long-finned pilot whale. Black in color, some individuals posses a light gray or white patch on the chin. Lighter, gray markings shaped like an anchor is present on the chest. The have muscular bodies with a thick tail . The forehead bulges over a beakless mouth. • The name pilot whaleis believed to originate from the idea that the pods or herds were piloted by a leader whale. • Due to their strong herding behavior, pilot whales are targeted by drive fisheries for their meat, blubber and oil. They are also incidentally taken by drift nets and trawlers.
Long-Finned Pilot Whale • Pilot whales are a slow swimming species that do not undertake long distance migrations, but primarily follow their prey. An adult male may be up to 6 m long (about 18 feet) and weigh about 3.5 tons. • Long-finned pilot whales are black with a pale anchor-shaped pattern on the throat and belly, and long flippers. They have a bulbous forehead, and low, swept-back dorsal fin. • Pilot whales are limited to the cooler parts of the globe. The northern and southern populations are separated by a band of warm tropical water so they can not meet.
Atlantic Humpbacked Dolphin • These dolphins are about a meter (3 feet) in length when born. When they are young, they do not have a hump. As they grow older, the hump will form just in front of it's dorsal fin, giving the dolphin its name. They are generally gray in color, with a lighter color along their underside, but can be slightly speckled. • Found along the west coast of Africa, they prefer shallow coastal waters, but may also be seen in estuaries and rivers, though they don't travel far upstream. They sometimes travel with and can be confused with bottlenose dolphins. However, as the dolphin ages, the hump does make them distinctive. They closely resemble the Atlantic Humpbacked dolphin, though the two species never mix.
False Killer Whale • The False killer whale is actually a member of the dolphin family, and is not a whale. Its resemblance to whales deceives people into thinking that it's a whale. When observed from a distance these animals look exactly like killer whales, however, when observed closely these are more slender and black in color as compared to killer whales. • It’s not only the appearance that makes these marine animals similar to whales. This species, just like killer whales, hunts its prey by a technique called herding, wherein a large group of false killer whales encircle the prey and pounce on it all at once.
Short-Finned Pilot Whale • The origin of the name is unclear, but two species are generally recognized: the short-finned pilot whale and the long-finned pilot whale. They are similar in appearance except for the pronounced difference in flipper length between the two species. • Short-finned pilot whales have a unique hunting style. It uses a fast, torpedo-like dive technique to hunt prey. When hunting prey, short-finned pilot whales can reach speeds of 32 kms. per hour (20 miles/hour) and hold that speed for up to 200 meters (650 feet).
Killer Whale • Killer Whales are the largest member of the dolphin family, and are known for their playfulness. • Many are found along the southwest coast of Canada but can be found in oceans worldwide. Natural-Born Killer: Also known by the name orca, it is an excellent hunter. All types of fish — from herring to white sharks, to marine mammals such as whales and seals, and even turtles and birds — are not safe when the orca is nearby. Orcas use several inventive techniques to catch their prey. One method is when large groups of orcas work as a team to herd victims together before attacking from different angles. Orcas will also frequently force seals and sea lions to beach, giving the hunter an easy catch in the shallow water. Tipping over ice floes to unbalance a tasty meal is another trick.