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白鸦的出现让温哥华岛的神秘之处更加鲜活

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2019年08月18日

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White raven sightings keep Vancouver Island mystery alive

白鸦的出现让温哥华岛的神秘之处更加鲜活

When photographer Mike Yip saw a flash of white on Vancouver Island in British Columbia in late May, the bright movement looked familiar. It wasn't the first time he had seen white ravens.

今年5月底,摄影师叶锦添(Mike Yip)在不列颠哥伦比亚省温哥华岛看到一道白色闪光时,这种明亮的运动看起来似曾相识。这已经不是他第一次看到白乌鸦了。

This time, the rare birds were two youngsters who were still with their parents. When he saw them again two weeks later, the birds were on their own.

这一次,稀有的鸟类是两只仍然和父母在一起的幼鸟。两周后,当他再次看到它们时,这些鸟已经独立了。

Photo: Mike Yip/www.vancouverislandbirds.com

Yip, a retired teacher who is a bird photojournalist, spotted the ravens in Coombs, a small community west of Qualicum Beach.

叶是一名退休教师,也是一名鸟类摄影记者。

Yip said he first heard of white ravens in the '90s before he was even interested in birding, but didn't see his first ones until 2007. Since then, he has photographed nine different white ravens.

叶说,他第一次听说白乌鸦是在90年代,那时他甚至对观鸟都不感兴趣,但直到2007年才第一次看到。从那时起,他已经拍摄了9只不同的白乌鸦。

But he rarely sees adult birds.

但他很少看到成年白乌鸦。

"With one or two white ravens born almost every year for 20 years, one would expect a lot of white ravens in the area. However, that is not the case," he tells MNN. "All the white ravens that I've seen have been first-year birds. I have never seen or heard of an adult white raven. My theory is that none of the ravens survive the the winter. They probably die of hypothermia because their feathers lack the thermal quality and strength of regular feathers."

“在过去的20年里,几乎每年都会有一到两只白乌鸦出生,人们预计这个地区会有很多白乌鸦。然而,事实并非如此。“我见过的所有白乌鸦都只有一岁。我从未见过或听说过成年白鸦。我的理论是没有一只白鸦能过冬。它们可能死于体温过低,因为它们的羽毛缺乏普通羽毛的热量和强度。”

Yip says his theory is supported by the observations of a friend whose neighbor fed ravens for several years. By late November, only the black siblings would show up, while the white siblings mysteriously disappeared. In addition, he says, two times over different years, there were reports of white raven bodies being found.

叶说,他的理论得到了一位朋友的观察结果的支持。到11月底,只有黑鸦兄弟姐妹会出现,而白鸦兄弟姐妹却神秘地消失了。此外,他说,在不同的年份里,有两次发现了白鸦尸体的报道。

This year's birds have blue eyes, which suggests they could have a genetic defect that prevents them from forming certain melanin pigments, Ben Freeman, a researcher at the University of British Columbia's Biodiversity Research Center, told the Vancouver Sun.

不列颠哥伦比亚大学生物多样性研究中心的研究人员本·弗里曼在接受《温哥华太阳报》采访时表示,今年的海鸟有蓝色的眼睛,这表明它们可能有基因缺陷,无法形成特定的黑色素。

Albino animals have no melanin anywhere in their bodies. Leucism is a partial loss of pigmentation.

白化病动物体内没有黑色素。白斑是色素沉着的部分丧失。

"Judging by the pictures, it's very close to albino, or leucistic," he said. "The genes that code for very white birds are in the area and could be turning up more often due to inbreeding."

“从照片上看,它非常接近白化病,或者说就是白化病,”他说。“为非常白的鸟类编码的基因就在该地区,由于近亲繁殖,这种基因可能出现得更频繁。”

Some situations make it easier than others to see Vancouver Island's white ravens, says Yip, who runs the site VancouverIslandBirds.com.

经营温哥华岛鸟类网站Vancouver islandbirds.com的叶先生说,有些情况下,看到温哥华岛的白乌鸦比其他情况要容易。

"Just after fledging, the raven family usually hangs around a location for a few weeks while the parents teach the fledglings survival skills. Sometimes the location is known and accessible to the public, and sometimes the location is unknown and sightings are just accidental. Last year the fledglings hung around a farm and the public was welcome to visit. This year there was no known location so sightings have been accidental and irregular."

刚孵出雏鸟时,乌鸦一家通常会在一个地方逗留几周,由父母教雏鸟生存技能。有时这个位置是已知的,公众可以进入,有时这个位置是未知的,目击只是偶然。去年,这些雏鸟在一个农场附近玩耍,欢迎公众参观。今年没有已知的地点,所以目击事件是偶然和不规则的。”


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