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Endangered species – Whales
Whales belong to cetaceans together with dolphins, but they're usually much bigger than the dolphins. There are more than 70 species of whales and dolphins and the largest whale in existence is the Blue Whale, being also the largest known mammal that has ever lived, and the largest living animal, at up to 35 m (105ft) long and 150 tons. Whales live for 40 to 200 years, depending on species although there aren't many whales over 100 years. Their communication is fascinating because they communicate with each other using lyrical sounds which are extremely loud because of their size and female whales are giving birth to a single calf. But many species, especially the large ones are endangered because of the commercial whaling, which took place during the 19th and the early 20th century. These large creatures have been hunted for oil, meat, baleen and ambergris (a perfume ingredient from the intestine of sperm whales).During the 19th century, whales were hunted primarily for oil and baleen, especially because before the electricity, many American homes were lighted with whale oil. Whaling and other threats have led to at least 5 of the 13 great whales being listed as endangered and thankfully Commercial whaling is subject to a moratorium by the International Whaling Commission (IWC) but some countries are still legitimately hunting whales like for instance Norway, Iceland, Japan and Canada.There are at this moment seven species of whales in U.S. waters that are protected under the Endangered Species Act. These are the blue whale, the bowhead whale, the fin whale, the humpback whale, the northern light whale, the sea whale and the sperm whale. All seven species are listed as endangered. Luckily there are also some positive things happening as well, especially in the grey whale population that has recovered so well that is removed from the endangered species' list. But for some other species it will take even more than one century to recover assuming there won't be further whaling so there's lot of uncertainties here. We can only hope for the best. It would be a real shame and disaster if these giants would disappear from the face of the Earth but unfortunately knowing humanity this isn't just some unreal possibility. Сetaceans – китообразные Bowhead whale – полярные гринландские киты Humpback whale – горбатый китб горбач Fin whale – сельдяной кит Sperm whale – кашалот What is the largest whale? What are specific features in communication of whales? What are the reasons of whales going extinct? Поиск по сайту: |
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