| 翻訳と辞書 |
| captive killer whales ： ウィキペディア英語版 |
captive killer whales
Killer whales were first captured live and displayed in exhibitions in the 1960s, soon becoming popular attractions at public aquariums and aquatic theme parks due to their intelligence, trainability, striking appearance, playfulness in captivity and sheer size. As of December, 2014, there are 57 orcas in captivity worldwide, 35 of which are captive-born.〔(The Fate of Captive Orcas in 2014 )〕 The practice of keeping killer whales in captivity has become controversial.〔(【引用サイトリンク】title=Orcas in captivity )〕
==Orcas==
(詳細はoceans, from the frigid Arctic and Antarctic regions to warm, tropical seas.
Killer whales are intelligent, versatile and opportunistic predators. Some populations feed mostly on fish, and other populations hunt marine mammals, including sea lions, seals, walruses and even large whales. They are considered an apex predator, having no natural predators in their environment. There are up to five distinct killer whale types, some of which may be separate races, subspecies or even species. Killer whales are highly social; some populations are composed of matrilineal family groups, which are the most stable of any animal species. The sophisticated social behavior, hunting techniques, and vocal behavior of killer whales have been described as manifestations of culture.
Although killer whales are not an endangered species, some local populations are considered threatened or endangered due to pollution by PCBs, depletion of prey species, captures for marine mammal parks, conflicts with fishing activities, acoustic pollution, shipping vessels, stress from whale-watching boats, and habitat loss.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「captive killer whales」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|