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Christmas bird-watching is in full swing in the U.S.A. When the holiday season comes, some Americans are likely to watch and count birds in the sky with great interest every day. This activity began in the early part of the last century. It has a one-hundred-year history. At that time, there was a so-called “holiday hunting” custom. In order to celebrate the holiday, the hunters went out to kill birds and beasts. By 1900, there were 27 bird lovers who decided to count birds instead of killing birds. Since then, Christmas bird-watching was held every year. It has been continued to the present.
There were 42000 people who took part in the bird-watching last Christmas, from December 16 the year before to January 3 next year. They were in the United States and Canada, Central America, South America and the Caribbean, watching and counting birds in the sky. The whole viewing area was divided into 1600 points. Each birdwatcher was responsible for 25 meters, and was demanded to write down the types and quantities of birds within 24 hours.
A birdwatcher described what he had watched vividly in his diary—“when I looked up, I saw a beautiful “landscape” in the sky: red-crowned cranes were driving up in cunning wedges that split the air. They were so neatly arranged, coordinating their movements. I was excited and breathtaking. Interestingly, the “human” shape always maintains 110°”.
“Why do red-crowned cranes choose to use ‘human’ shape when flying in formation?” He continued, “In my opinion,there are four reasons: First, the ‘human’ shape can make red-crowned cranes use increasing air which is produced by each other’s wings when they are swinging in the sky. It can increase the glide time and save physical ability. Second, the ‘human’ shape will enhance communication among the birds. The orders and the relevant information issued by the lead bird can be conveyed to each member in this migratory group unimpeded, accurately, rapidly and conveniently. Third, such a formation will help to find the birds left behind because of feeling run down as fast as possible, so that the young, the weak, the sick birds can get everyone’s help and encouragement. Finally, the ‘human’ shape shows not only beauty but also unity. It can give enemies a deterrent. They will be terrified and did not dare to attack the birds. The migration security of the birds will be ensured.”
Environmental experts admired and evaluated Christmas bird-watching highly. They pointed out that it made perfect sense. On the one hand it could enhance the human awareness of environmental protection. On the other hand it could provide first-hand information on birds.
在美国,圣诞节前后观鸟达到高潮。每当节日来临,一些美国人都饶有兴趣地天天观察和数一数天上的飞鸟。这项活动始于上世纪初,已有百年历史。当时的圣诞节有一个所谓的“节日猎杀”习俗,届时猎人们纷纷出动,捕杀飞禽走兽,以庆祝节日。到了1900年,有27名鸟类爱好者决定改用数鸟来代替对鸟类的捕杀。从此以后,圣诞数鸟的活动年年举行,一直持续至今。
去年的圣诞数鸟活动共有4.2万人参加,从前一年12月16日到第二年元月3日,他们在美国和加拿大、中美洲、南美洲以及加勒比海等地观赏和数鸟。整个观察区域分成1600个点,每一个观鸟者要求负责25米的区域范围,并且记下24小时之内所看到的鸟的种类和数量。
有一位观鸟者在观察日记中这样生动地加以描写——“当我抬头遥望天空时,看到一道美丽的‘风景’: 丹顶鹤以‘人’字形飞行,它们排列得那么整齐,动作如此协调,令人叹为观止。有趣的是,‘人’字形的角度永远保持110°”
“那么丹顶鹤在编队迁飞时,何以要选用‘人’字形呢? ”他继续写道,“我分析有4个原因:首先,这种形状的飞行可以让丹顶鹤利用彼此间的翅膀在摆动时所产生的上升气流,从而增加滑翔时间,节约体能。其次,‘人’字的编队能够增进鸟与鸟之间的‘交流’,领头鸟发出的有关信息和命令可以畅通无阻,准确、迅速、方便地传达给这个迁飞集体中的每一个成员。第三,这种编队有利于及时发现因体力不支而掉队的伙伴,使年幼的、体弱的、生病的鸟得到大家的帮助和鼓励。最后一点是,‘人’字形的队伍不但充满美感,而且显得团结,能够给天敌以一种威慑力量,使其望而生畏而不敢发起进攻。确保迁飞的安全。”
环境专家对圣诞数鸟活动大加赞赏,给予了高度评价。他们指出,此举很有意义,一方面可以增强人类保护环境的意识,另一方面能提供有关鸟类的第一手资料。
There were 42000 people who took part in the bird-watching last Christmas, from December 16 the year before to January 3 next year. They were in the United States and Canada, Central America, South America and the Caribbean, watching and counting birds in the sky. The whole viewing area was divided into 1600 points. Each birdwatcher was responsible for 25 meters, and was demanded to write down the types and quantities of birds within 24 hours.
A birdwatcher described what he had watched vividly in his diary—“when I looked up, I saw a beautiful “landscape” in the sky: red-crowned cranes were driving up in cunning wedges that split the air. They were so neatly arranged, coordinating their movements. I was excited and breathtaking. Interestingly, the “human” shape always maintains 110°”.
“Why do red-crowned cranes choose to use ‘human’ shape when flying in formation?” He continued, “In my opinion,there are four reasons: First, the ‘human’ shape can make red-crowned cranes use increasing air which is produced by each other’s wings when they are swinging in the sky. It can increase the glide time and save physical ability. Second, the ‘human’ shape will enhance communication among the birds. The orders and the relevant information issued by the lead bird can be conveyed to each member in this migratory group unimpeded, accurately, rapidly and conveniently. Third, such a formation will help to find the birds left behind because of feeling run down as fast as possible, so that the young, the weak, the sick birds can get everyone’s help and encouragement. Finally, the ‘human’ shape shows not only beauty but also unity. It can give enemies a deterrent. They will be terrified and did not dare to attack the birds. The migration security of the birds will be ensured.”
Environmental experts admired and evaluated Christmas bird-watching highly. They pointed out that it made perfect sense. On the one hand it could enhance the human awareness of environmental protection. On the other hand it could provide first-hand information on birds.
在美国,圣诞节前后观鸟达到高潮。每当节日来临,一些美国人都饶有兴趣地天天观察和数一数天上的飞鸟。这项活动始于上世纪初,已有百年历史。当时的圣诞节有一个所谓的“节日猎杀”习俗,届时猎人们纷纷出动,捕杀飞禽走兽,以庆祝节日。到了1900年,有27名鸟类爱好者决定改用数鸟来代替对鸟类的捕杀。从此以后,圣诞数鸟的活动年年举行,一直持续至今。
去年的圣诞数鸟活动共有4.2万人参加,从前一年12月16日到第二年元月3日,他们在美国和加拿大、中美洲、南美洲以及加勒比海等地观赏和数鸟。整个观察区域分成1600个点,每一个观鸟者要求负责25米的区域范围,并且记下24小时之内所看到的鸟的种类和数量。
有一位观鸟者在观察日记中这样生动地加以描写——“当我抬头遥望天空时,看到一道美丽的‘风景’: 丹顶鹤以‘人’字形飞行,它们排列得那么整齐,动作如此协调,令人叹为观止。有趣的是,‘人’字形的角度永远保持110°”
“那么丹顶鹤在编队迁飞时,何以要选用‘人’字形呢? ”他继续写道,“我分析有4个原因:首先,这种形状的飞行可以让丹顶鹤利用彼此间的翅膀在摆动时所产生的上升气流,从而增加滑翔时间,节约体能。其次,‘人’字的编队能够增进鸟与鸟之间的‘交流’,领头鸟发出的有关信息和命令可以畅通无阻,准确、迅速、方便地传达给这个迁飞集体中的每一个成员。第三,这种编队有利于及时发现因体力不支而掉队的伙伴,使年幼的、体弱的、生病的鸟得到大家的帮助和鼓励。最后一点是,‘人’字形的队伍不但充满美感,而且显得团结,能够给天敌以一种威慑力量,使其望而生畏而不敢发起进攻。确保迁飞的安全。”
环境专家对圣诞数鸟活动大加赞赏,给予了高度评价。他们指出,此举很有意义,一方面可以增强人类保护环境的意识,另一方面能提供有关鸟类的第一手资料。