Before we take a look at whale watching, we should take a moment to get to know these magnificent animals ... What's a Cetacean? Cetaceans are mammals that live their entire lives in the water and include whales, dolphins and porpoises. They have hair, breathe air, are warm-blooded and bear live young that drink their mother's milk. There are two types of cetaceans: the toothed whales, which (obviously) have teeth and include all porpoises and dolphins. (Dolphins and porpoises have different types of teeth: dolphins' teeth are sharp, while porpoises have flatter, shovel-shaped teeth.) And the baleen whales, which have giant comb-like structures on their jaws that are used to sift food, such as shrimp-like krill, from the water. Humpbacks (that pass by my neighbourhood) and Blue whales are baleen whales. Baleen whales can eat up to 9,000 pounds of fish and krill daily. This hearty appetite is due to the fact that they don't eat all year round, usually feeding about half the year in the cold, nutrient-rich waters of their summer feeding grounds. They store huge amounts of fat or blubber to get them through the breeding season. The largest whale is the Blue whale, which can grow up to 100 feet long and weigh up to 190 tons, and the deep-diving Sperm whale can go down 5,000 feet and stay down for more than an hour. Whale Songs In the late 1960s, whale biologist Roger Payne discovered that humpback whales "sing" to each other and themselves. After researching this phenomenon, scientists now know that while both male and female humpbacks can produce sounds, only the males appear to produce organised songs with distinct themes and melodies, and almost always on breeding grounds. Apparently the males often sing while suspended deep below the surface, their long front flippers jutting rigidly from their sides. The songs can last up to 20 minutes and can be heard more than 20 miles away. The male may repeat the same song dozens of times over several hours and whales in the same geographic area sing in very similar "dialects." Song patterns can change gradually over time, so new songs emerge every few years. Researchers still aren't sure exactly how the whales produce the sounds and since whales don't have vocal cords, they probably sing by circulating air through the tubes and chambers of their respiratory system. But no air escapes during the concerts -- and their mouths don't move! There are some theories about why the whales sing, and while scientists originally believed they were a mating call, used to advertise the male's availability to passing females, they've since come up with another theory. Some researchers now believe that the singing humpbacks are actually issuing threats, not singing love songs, because many of the whales approaching singers were other males and the meeting would often end in a tussle. We may never know exactly why these whales produce their songs of creaks, groans and moans. This is an excellent place to begin your acquaintance with whales and has links to sites around the globe: http://www.physics.helsinki.fi/whale/ The south-east coast of New South Wales provides one of the best places to observe whales during their northern migration: http://www.sapphirecoast.com.au/whales/default.htm This region was once the centre of whaling operations that took hundreds of mammals each season to be turned into oil, perfume and corsets for rich ladies! (Read about ambergris and perfume here: http://www.write101.com/W.Tips374.htm ) Queensland (the north-east coast of Australia) has information on the behaviour and habitat of the Humpback whale (the most common whale in this part of the world): http://www.dkd.net/whales/ You can subscribe to a free newsletter that gives you weekly updates of the movement of whales around the world: http://www.whales-online.org/ You'll also discover all the ways our modern way of life threatens the survival of these wonderful mammals. |
