蓝鲸的资料英语

下面的应该足够了吧The Blue Whale (Balaenoptera musculus) is a marine mammal belonging to the suborder of baleen whales. At up to 33 metres (110 ft) in length and 181 metric tonnes (200 short tons) or more in weight, it is believed to be the largest animal to have ever lived on Earth,[2] though some recent, albeit controversial, dinosaur discoveries may contradict this long-held belief (see Bruhathkayosaurus).Blue Whales were abundant in nearly all oceans around the world until the beginning of the twentieth century. For the first 40 years of the century they were hunted by whalers almost to extinction. Hunting of the species was outlawed by the international community in 1966. A 2002 report estimated there were 5,000 to 12,000 Blue Whales worldwide[3] located in at least five groups. More recent research into the Pygmy subspecies suggest this may be an underestimate.[4] Before whaling the largest population 239,000 (range 202,000 to 311,000) was in the Antarctic[5] but now there remain only much smaller (around 2,000) concentrations in each of the North-East Pacific, the Antarctic, and the Indian Ocean. There are two more groups in the North Atlantic and at least two in the Southern Hemisphere.Since the whaling ban, it is not well known whether the global Blue Whale population is increasing or remaining stable. In the Antarctic, best estimates show a significant increase at 7.3% per year since the end of illegal Soviet Union whaling, but numbers remain at under 1% of their original levels.[5] It has also been suggested that Icelandic and California populations are increasing but these increases are not statistically significant. The total world population was estimated to be between 5,000 and 12,000 in 2002 although there is great uncertainty in available estimates for many areas.[3] The Blue Whale remains listed as "endangered" on the IUCN Red List of threatened species as it has been since the list's inception. The largest known concentration, consisting of about 2,000 individuals, is the North-East Pacific population that ranges from Alaska to Costa Rica but is most commonly seen from California in summer. Sometimes this population strays over to the North-West Pacific; infrequent sightings between Kamchatka and the northern tip of Japan have been recorded.In the Southern Hemisphere, there appear to be two distinct subspecies, the Antarctic blue whale and the poorly-understood Pygmy blue whale, found in Indian Ocean waters. Recent abundance estimates for the Antarctic subspecies range from 1100[15] to 1700.[5] Research into the number of Pygmy Blues is on-going. Estimates from a 1996 survey were that 424 pygmy blue whales were in a small area south of Madagascar alone,[16] thus it is likely that numbers in the entire Indian Ocean are in the thousands or more. If this is true, the global numbers are much higher.[4]Migratory patterns of these subspecies are not well known. For example, pygmy blue whales have been recorded in the northern Indian Ocean (Oman, Maldives, Sri Lanka) where they may form a distinct resident population. In addition, the population of Blue Whales occurring off Chile and Peru may also be a distinct population. Some Antarctic blue whales approach the eastern South Atlantic coast in winter, and occasionally their sounds are heard off Peru, Western Australia, and in the northern Indian Ocean. In Chile, the Cetacean Conservation Center, with support from the Chilean Navy, is undertaking extensive research and conservation work on a recently discovered feeding aggregation of the species off the coast of Chiloe Island.In the North Atlantic, two stocks are recognized. The first is found off Greenland, Newfoundland, Nova Scotia and the Gulf of Saint Lawrence. This group is estimated to total about 500. The second, more eastern group is spotted from the Açores in Spring to Iceland in July and August; it is presumed that the whales follow the Mid-Atlantic Ridge between the two volcanic islands. Beyond Iceland, Blue Whales have been spotted as far north as Spitsbergen and Jan Mayen though such sightings are rare. Scientists do not know where these whales spend their winters. The total North Atlantic population is between 600 and 1500.Human threats to the potential recovery of Blue Whale populations include the accumulation of polychlorinated biphenyl (PCB) chemicals within the whale's blood, causing poisoning and premature death, and the ever-increasing amount of noise created by ocean traffic. This noise drowns out the noises produced by whales (see whale song), which may make it harder for whales to find a mate.Efforts to calculate the Blue Whale population more accurately are supported by marine mammologists at Duke University who maintain the OBIS-SEAMAP (Ocean Biogeographic Information System - Spatial Ecological Analysis of Megavertebrate Populations), a collation of marine mammal sighting data from around 130 sources.[17]蓝鲸（学名Balaenoptera musculus，英文blue whale）是一种海洋哺乳动物，属於须鲸亚目。蓝鲸被认为是曾经生存过的最大动物，长可达30米，重140吨或更多。直到20世纪初，世界上许多海洋中的蓝鲸还是很丰富的。20世纪的前40年，它们被捕鲸者猎杀几乎灭绝。1966年国际社会将捕猎这一物种定为非法。现在世界上的数量在三千到四千头之间。这些蓝鲸位於四个（也许五个）群体中。最大的群体在东北太平洋。有两个群体在北大西洋，一个在南极水域。在印度洋发现的蓝鲸可能是，或者不是南极群体的一部分。禁止捕鲸以来，全球蓝鲸的数量基本保持不变，大概3000－4000头。从受胁物种红色列表创立开始，蓝鲸就已经被列为红色列表上的濒危物种。位於太平洋东北部的蓝鲸种群是最大的，由大约2000个体组成，集中在阿拉斯加到哥斯大黎加之间，但在夏季常见於加利福尼亚。这个种群是长期以后蓝鲸数量回升的希望。有些时候他们会漂泊到太平洋西北部；曾有记载出现在堪察加半岛和日本北端之间。南大洋蓝鲸种群的数量在750-1200头之间，该种群迁移的方式还没良好理解。它们可能是，也可能不是区别於斯里兰卡东北沿海时常出现不确定数目的种群。南大洋种群的一部分蓝鲸接近南太平洋的东海岸。在智利，人们发现了蓝鲸聚集於智鲁岛沿岸觅食，因此智利鲸类保护中心，在智利海军的支持下，对其进行广泛的研究和保护。在北大西洋生活著两个蓝鲸种群。第一个位於格陵兰，纽芬兰，新斯科舍和圣劳伦斯湾。估计有500头左右。第二个更靠东，春季出现在亚述尔群岛，而七八月份则出现在冰岛；据推测鲸群沿大西洋中脊在这两个火山岛之间活动。除了冰岛，虽然及其少见，蓝鲸还出现在更远的斯瓦尔巴群岛和扬马延岛。科学家不清楚这些蓝鲸在哪里过冬。整个北大西洋的种群数量在600-1500之间。人类对蓝鲸种群的恢复造成威胁，多氯联二苯化学品会在蓝鲸血液内聚集，导致蓝鲸中毒和夭折，同时日益增加的海洋运输造成的噪音，掩盖了蓝鲸的声音（见鲸歌），导致蓝鲸很难找到配偶。