|
![]() |
![]() |
![]() |
|
|
![]() ![]() Whales are the giants of the sea. If you are ever lucky enough to see a great whale swimming in the ocean, you will never forget it! Despite being huge animals, whales are not easy to spot because they glide silently along, creating hardly a ripple. They only give themselves away when they come up to breathe and send up gigantic spouts of air and water from their blowholes. Whales are divided into two groups. The baleen or whalebone whales have no teeth, only a flexible horny substance called baleen, which looks like a sieve or strainer, suspended from the upper jaw. The baleen group of whales has 10 species, including most of the enormous whales. The other group is the toothed whales which have teeth. This group has 66 species and includes sperm whales, killer whales, dolphins and porpoises. The largest of the baleen whales, the Blue Whale, may reach more than 30m long and weigh as much as 130 tonnes. That’s as much as the combined weight of 30 average-sized elephants! Toothed whales are smaller but vary in size, from 1.3m long dolphins to the 18m Sperm Whale that weighs almost 70 tonnes. ![]()
Life under water Whales are mammals which returned to the sea more than 40 million years ago and assumed a fish-like form. Their hind limbs disappeared and their front limbs evolved into flippers. Although they breathe air, whales cannot survive on land. Whales that accidentally get stranded on a beach soon die, because the great weight of their bodies crushes their internal organs. While most whales are ocean-going animals, there are some freshwater species which belong to the toothed whale group. Whales move their body through the water with the help of their horizontal tail which flaps up and down. Whales can reach astounding speeds. Killer whales can reach 60 kph, some dolphins 30 kph, while the large Fin Whale cruises along at 22 to 26 kph. Right Whales and Grey Whales are somewhat slower, with a top speed of about 11 kph.
![]() Whales have a thick layer of fat called blubber under their smooth, almost hairless skin which helps them retain their body heat. "There she blows!" Whales can dive deeply and stay down a long time. The Sperm Whale, for instance, can dive down more than 2000m and remain below the surface for up to 90 minutes! Like land mammals, whales have lungs and come to the surface of the water to breathe through their nostrils. A whale's nostrils are called the "blowhole", situated at the top of the head. A surfacing whale exhales warm air and moisture from its blowhole in a huge fountain. This was mistaken by old-time whalers for a spout of water. You can identify a whale species by the size and shape of its "blow"! What do whales eat? Whales with baleens sieve out plankton, squid and small fish from seawater. Toothed whales prey on a variety of fish and squids. Whales swallow their food whole and have a muscular compartment to their stomach which crushes their food. The song of the whale. Most whales are social animals and some travel in groups called "pods". Whales communicate with each other by singing complex songs made up of a variety of whistles, clicks, low and high-pitched moans, grunts and groans. Some of these sounds are too high or too low-pitched for us to hear, but the noise travels long distances under water. In fact, whale songs are quite beautiful, even to human ears! Raising young A Baleen whale baby is born 11 months after mating. Some toothed whales have longer pregnancies. Whales only have one baby at a time and the baby is born tail first and is fully developed. Most whales nurse their young ones for about six-seven months. Conservation Concern Whales have been hunted for centuries for their blubber, oils, meat and baleen. Overhunting in the past has brought seven of the eleven great whale species near extinction. Even though most commercial whaling stopped thirty years ago, most of these species have not recovered to their original numbers. The northern right whale shows no recovery at all and is the most endangered large whale. There may be as few as 500 blue whales left in the southern hemisphere. WWF has made saving Whales a top priority. It continues to put pressure on countries which want to resume hunting whales not to do so. WWF and other organizations were instrumental in getting the whole of the Southern Ocean and the Indian Ocean declared international Whale Sanctuaries. |
|
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |