白鴉的出現(xiàn)讓溫哥華島的神秘之處更加鮮活

白鴉的出現(xiàn)讓溫哥華島的神秘之處更加鮮活

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，攝影師葉錦添(Mike Yip)在不列顛哥倫比亞省溫哥華島看到一道白色閃光時，這種明亮的運動看起來似曾相識。這已經(jīng)不是他第一次看到白烏鴉了。

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.

這一次，稀有的鳥類是兩只仍然和父母在一起的幼鳥。兩周后，當他再次看到它們時，這些鳥已經(jīng)獨立了。

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.

葉是一名退休教師，也是一名鳥類攝影記者。

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.

葉說，他第一次聽說白烏鴉是在90年代，那時他甚至對觀鳥都不感興趣，但直到2007年才第一次看到。從那時起，他已經(jīng)拍攝了9只不同的白烏鴉。

But he rarely sees adult birds.

但他很少看到成年白烏鴉。

"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."

“在過去的20年里，幾乎每年都會有一到兩只白烏鴉出生，人們預計這個地區(qū)會有很多白烏鴉。然而，事實并非如此。“我見過的所有白烏鴉都只有一歲。我從未見過或聽說過成年白鴉。我的理論是沒有一只白鴉能過冬。它們可能死于體溫過低，因為它們的羽毛缺乏普通羽毛的熱量和強度。”

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.

葉說，他的理論得到了一位朋友的觀察結(jié)果的支持。到11月底，只有黑鴉兄弟姐妹會出現(xiàn)，而白鴉兄弟姐妹卻神秘地消失了。此外，他說，在不同的年份里，有兩次發(fā)現(xiàn)了白鴉尸體的報道。

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.

不列顛哥倫比亞大學生物多樣性研究中心的研究人員本·弗里曼在接受《溫哥華太陽報》采訪時表示，今年的海鳥有藍色的眼睛，這表明它們可能有基因缺陷，無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.

白化病動物體內(nèi)沒有黑色素。白斑是色素沉著的部分喪失。

"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."

“從照片上看，它非常接近白化病，或者說就是白化病，”他說。“為非常白的鳥類編碼的基因就在該地區(qū)，由于近親繁殖，這種基因可能出現(xiàn)得更頻繁。”

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

經(jīng)營溫哥華島鳥類網(wǎng)站Vancouver islandbirds.com的葉先生說，有些情況下，看到溫哥華島的白烏鴉比其他情況要容易。

"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."

剛孵出雛鳥時，烏鴉一家通常會在一個地方逗留幾周，由父母教雛鳥生存技能。有時這個位置是已知的，公眾可以進入，有時這個位置是未知的，目擊只是偶然。去年，這些雛鳥在一個農(nóng)場附近玩耍，歡迎公眾參觀。今年沒有已知的地點，所以目擊事件是偶然和不規(guī)則的。”