Реферат на тему Humpback Whale Essay Research Paper Humpback WhaleIntroductionAs
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Humpback Whale Essay, Research Paper
Humpback Whale
Introduction
As the boat sways up and down, hours take years to complete, and the anticipation grows to see that one element of the whole trip. That element being the site of the enormous tail fin of a humpback whale. These trips are often taken via television for most people, but there are a select few who see the real thing. The humpback whale is usually unseen and forgotten. But this beautiful creature has been around a long time and if forgotten someday could be extinct.
Discussion
The humpback whale as seen in the eyes of the famous writer, Herman Melville, “He has a great back on him like a peddler; or you might call him the Elephant and Castle whale (Ellis, 59). ” The description of the hump was near perfect, but as for the name he was not even close. The humpback is a shorter and stockier whale, on the average they reach about fifty feet in length and thirty-two tons ( not including blood ). Generally the colors are black above and white below, but many combinations have been seen (60). The humpback whale has a very large head and spacious mouth cavity. The two long rows of baleen plates strain the water for minute organisms. Its skull is very symmetrical and the brain cavity is small. The whale breathes through a blowhole on the top of the body and nostrils above the mouth. As for the fins, the dorsal fin is small and some lack them, the swimmers allow this huge creature to leap from the water (Grzimek 327). The humpback whale belongs to the phylum Chordata, class Mammalia, and the order Cetacea. This aquatic animal belongs in the suborder Mysticeti, these are the baleen whales which have three families and several species. The family is called Balaenopteridae, meaning true fin backed whale. The genus name is Megaptera meaning great wing, and this separates it from other genus. And lastly the species name that is Megaptera novaeangliae (Cousteau 84). The common everyday term is humpback whale.
The humpback whale tends to migrate singly, in pairs, or occasionally in larger schools. They migrate to cold ocean regions where food is plentiful. They have a short food chain compared to most mammals. Phytoplankton turns sunlight into energy and this energy is consumed by zooplankton. The zooplankton and phytoplankton are then eaten by small fish. The whale in turn eats the fish, making it a predator of the sea. The food chain completes when waste products and dead whales decompose. Their filter feeding method is quit simple, and very effective (Kauffman 55). They take huge amounts of water into their mouth using a gulping method and then when they push the water out, they put their tongue up so the water must pass through the baleens. The food is then trapped and falls toward the rear of the mouth. The two gulping methods humpback whales use are the lunge feeding and bubble net feeding. Lunge feeding is used when food is abundant, the whale simply swims through prey with its mouth open engulfing prey. Bubble net is used when prey is less abundant, the whale plunges below the prey and discharges bubbles from the blowhole. The bubbles form a net and stun the prey and the whale simply swims upward and fills its mouth (56). Humpback whales consume nearly a ton of food daily and that is how it’s done.
The humpback whale breed in the same areas every year. The offspring of humpback whales is known as a calf and it is a live birth. A normal pregnancy bears one calf a year, but there are known cases of them having twins. The calf usually weighs from 990 to 14,300 pounds (Schilling, 1). The newborn calf can reach lengths of twelve to fourteen feet. The humpback mother and her “escort,” stay with the calf nursing it and teaching how to dive, hold its breath, breach, and many other survival tips. The humpbacks reach sexual maturity at the age of seven. And the oldest known humpback died at the age of forty-seven in Australian waters (Ellis, 62). Humpback males have unique mating rituals. The male points his head down in the water and his tail up, and repeats certain sounds for long periods of time. These “songs” can be become hauntingly beautiful, but the females love them (Wursig, 1).
The humpback whale most spectacular activity of all, is breaching: the whale throws itself out of the water, flippers extended, and then lands on its back or side and makes a awesome splash. This activity is graceful, but it has a specific function among whales. When the water is…
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