Chapter one Understanding Whales, Dolphins & Porpoises
Chapter one
Understanding Whales, Dolphins & Porpoises
The world of Whales, Dolphins & Porpoises
Whales, dolphins & porpoises belong to a single group of marine mammals known as the cetaceans.
A tool of 81 different species are currently recognized by whale experts although, as research progress, new ones of are still being discovered. A strange skull, for example, was found in the Juan Fernandez Islands, off the coast of Chile, in June 1986. After nearly a decade of painstaking examination and scientific discussion, a team of whale experts finally concluded that this discovery was to science. It was named Bahamonde’s beaked whale in 1996, making it the most recent cetacean species to be formally recognized. Although believed to be a living species, no live representatives of this whale have yet been seen. Meanwhile, a number of other cetaceans species have been split in recent years. In 1995, for example, the common dolphin was officially separated into two distinct species, now known as the long-beaked common dolphin and the short-beaked common dolphin.
Infinity Variety
Inevitably, whale, dolphins & porpoise share many features in common. Yet they also come in an impressive variety of shapes, sizes & colors; live in many different marine & freshwater habitats; & have developed a bewildering variety of adaptations for survival in their underwater world.
Some live in shallow water close to shore, or in major rivers & estuaries, while others live so far out to sea that they probably never set eyes on land from the day they are born until the day they die. Some are fairly common & widespread, while others are on the verge of extinction.
They range in size from several small dolphins & porpoises, as little as 4 feet (1.2 m) in length, to the enormous blue whale, which can grow to more than 98 feet (30 m) in length, almost as long as a Boeing 737.
Some species are brightly coloured, with a motley collection of spots & stripes, several have striking black & white markings, while others are a relatively drab brown or gray. Some are long & slender, others short & robust. Some have tall, scythe-shaped dorsal fins; others species have much smaller, triangular fins at all. There are even variations among individuals of the same species: between males & females, youngsters & adults, & among populations in different parts of the world.
Physical Variation
The short beaked common dolphin. Atlantic spotted. At the far right, pilot whale, & the small dorsal fin of a humpback whale.
Special Appeal
There is something special & particularly appealing about cetaceans. This is difficult to put into words, & impossible to prove, yet it is a feeling shared by a great many people. Some claim it is because of their apparent intelligence; others are in awe that air-breathing mammals, like us, are able to thrive in such an alien underwater world. Some people are inspired by their ability to explore place out of our reach, experience, things we will never experience, & see things we will never see.
Others see them as we would like to see ourselves-free, graceful, compassionate, peaceful, & full of energy.
Undoubtedly, the amazing sense of mystery surrounding these enigmatic creatures is itself a major part of their appeal. We now know that many of our early assumptions about them were wrong or, at least, were not entirely accurate. Yet the more we learn about these incredible creatures, the more intriguing their story become.
Record Beakers
Perfectly adapted to life underwater, whales, dolphins, & porpoises are the record breakers of the animal kingdom. Here are a few examples:
Understanding Whales, Dolphins & Porpoises
The world of Whales, Dolphins & Porpoises
Whales, dolphins & porpoises belong to a single group of marine mammals known as the cetaceans.
A tool of 81 different species are currently recognized by whale experts although, as research progress, new ones of are still being discovered. A strange skull, for example, was found in the Juan Fernandez Islands, off the coast of Chile, in June 1986. After nearly a decade of painstaking examination and scientific discussion, a team of whale experts finally concluded that this discovery was to science. It was named Bahamonde’s beaked whale in 1996, making it the most recent cetacean species to be formally recognized. Although believed to be a living species, no live representatives of this whale have yet been seen. Meanwhile, a number of other cetaceans species have been split in recent years. In 1995, for example, the common dolphin was officially separated into two distinct species, now known as the long-beaked common dolphin and the short-beaked common dolphin.
Infinity Variety
Inevitably, whale, dolphins & porpoise share many features in common. Yet they also come in an impressive variety of shapes, sizes & colors; live in many different marine & freshwater habitats; & have developed a bewildering variety of adaptations for survival in their underwater world.
Some live in shallow water close to shore, or in major rivers & estuaries, while others live so far out to sea that they probably never set eyes on land from the day they are born until the day they die. Some are fairly common & widespread, while others are on the verge of extinction.
They range in size from several small dolphins & porpoises, as little as 4 feet (1.2 m) in length, to the enormous blue whale, which can grow to more than 98 feet (30 m) in length, almost as long as a Boeing 737.
Some species are brightly coloured, with a motley collection of spots & stripes, several have striking black & white markings, while others are a relatively drab brown or gray. Some are long & slender, others short & robust. Some have tall, scythe-shaped dorsal fins; others species have much smaller, triangular fins at all. There are even variations among individuals of the same species: between males & females, youngsters & adults, & among populations in different parts of the world.
Physical Variation
The short beaked common dolphin. Atlantic spotted. At the far right, pilot whale, & the small dorsal fin of a humpback whale.
Special Appeal
There is something special & particularly appealing about cetaceans. This is difficult to put into words, & impossible to prove, yet it is a feeling shared by a great many people. Some claim it is because of their apparent intelligence; others are in awe that air-breathing mammals, like us, are able to thrive in such an alien underwater world. Some people are inspired by their ability to explore place out of our reach, experience, things we will never experience, & see things we will never see.
Others see them as we would like to see ourselves-free, graceful, compassionate, peaceful, & full of energy.
Undoubtedly, the amazing sense of mystery surrounding these enigmatic creatures is itself a major part of their appeal. We now know that many of our early assumptions about them were wrong or, at least, were not entirely accurate. Yet the more we learn about these incredible creatures, the more intriguing their story become.
Record Beakers
Perfectly adapted to life underwater, whales, dolphins, & porpoises are the record breakers of the animal kingdom. Here are a few examples:
- The blue whale is largest animal on Earth. They heaviest ever recorded was a female weighing 209 tons (190 tonnes), caught in the Southern Ocean in 1947. The longest was another female, also landed in the Southern Ocean, in 1909, measuring 110 feet, 2 inches (33.5 m) from the tip of her snout to the end of her tail.
- The low-frequency pulse made by blue Whales & fin whales, when communicating with members of their own species across enormous stretches of ocean, have been measured at up to 188 decibels-the loudest sounds emitted by any living source.
- The longest & most complex songs in the animal kingdom are sung by male humpback whales. Each song can last for half an hour or more & consists of several main components.
- The humpback whale also undertakes the longest documented migration of any individual mammal (a record previously believed to be held by the gray whale). One humpback, for example, was observed at its feeding grounds near the Antarctic Peninsula & , less than five months later, was seen again at its breeding grounds off the coast of Colombia. The shortest swimming distance between these two locations is 5,176 miles (8,334 km).
- The sperm whale is believed to dive deeper than any other mammal. The deepest known dive was 6,560 feet (2,000 m), recorded in 1991. It was made by male sperm whale diving off the coast of Dominica, in the Caribbean. Indirect evidence suggests that sperm whales may be able to dive to depths of at least 10,000 feet (3,000 m). The record for the longest dive by any mammal is also held by the sperm whale; on November 1983, biologist working in the southwest Caribbean listened to five sperm whales clicking underwater during a dive lasting an astonishing 2 hours 18 minutes.
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