自1970年以來，北美已經(jīng)有近30億只鳥類消失

自1970年以來，北美已經(jīng)有近30億只鳥類消失

If your backyard bird feeder seems a little less popular these days, it's not your imagination.

如果你的后院喂鳥器現(xiàn)在看起來不那么受歡迎，那不是你的想象。

Grassland birds like meadowlarks were particularly affected over the past half-century. (Photo: Jack Dean III/Shutterstock)

The number of birds in the U.S. and Canada has plummeted over the past 50 years, dropping by 29%, according to a study published in the journal Science. That's an overall decline of 2.9 billion birds since 1970.

發(fā)表在《科學(xué)》(Science)雜志上的一項(xiàng)研究顯示，美國和加拿大的鳥類數(shù)量在過去50年中大幅下降，下降了29%。自1970年以來，鳥類總數(shù)下降了29億。

The study found there were large losses for every type of bird, from songbirds to those that migrate long distances.

研究發(fā)現(xiàn)，從鳴禽到長距離遷徙的鳥類，每一種鳥類都有很大的損失。

For the analysis, researchers included citizen scientist data from information collections such as the North American Breeding Bird Survey and the Audubon Christmas Bird Count. They also used data from 143 weather radar stations to look for declines in migratory bird populations. Additionally, they studied 50 years of data collected from on-the-ground monitoring.

為了進(jìn)行分析，研究人員收集了來自北美種鳥調(diào)查和奧杜邦圣誕鳥類統(tǒng)計(jì)等信息收集機(jī)構(gòu)的公民科學(xué)家數(shù)據(jù)。他們還利用143個氣象雷達(dá)站的數(shù)據(jù)來尋找候鳥數(shù)量下降的情況。此外，他們還研究了50年來從地面監(jiān)測中收集的數(shù)據(jù)。

Grassland birds, such as meadowlarks and sparrows, were particularly affected. They experienced a 53% drop in population — more than 720 million birds — since 1970. So many of these birds have likely disappeared due to modern agriculture and development, as well as pesticide use.

草原鳥類，如草地云雀和麻雀，受到的影響尤為嚴(yán)重。自1970年以來，它們的數(shù)量下降了53%——超過7.2億只。由于現(xiàn)代農(nóng)業(yè)和發(fā)展，以及殺蟲劑的使用，這些鳥類中的許多可能已經(jīng)消失了。

Shorebirds were also hard hit because of their sensitive coastal habitats. Their populations were already "dangerously low," researchers said, but they've since lost more than one-third of their numbers.

濱鳥也因其敏感的沿海棲息地而遭受重創(chuàng)。研究人員說，它們的數(shù)量已經(jīng)“低得危險(xiǎn)”，但自那以后，它們的數(shù)量減少了三分之一以上。

The researchers tracked spring migration using radar in the night skies. They found that in just the past decade, it dropped by 14%.

研究人員利用夜空中的雷達(dá)跟蹤春季遷徙。他們發(fā)現(xiàn)，就在過去的十年里，這個數(shù)字下降了14%。

"It's imperative to address immediate and ongoing threats, both because the domino effects can lead to the decay of ecosystems that humans depend on for our own health and livelihoods — and because people all over the world cherish birds in their own right. Can you imagine a world without birdsong?"

“我們必須應(yīng)對迫在眉睫的和持續(xù)不斷的威脅，這既是因?yàn)槎嗝字Z骨牌效應(yīng)可能導(dǎo)致人類賴以生存和健康的生態(tài)系統(tǒng)的衰退，也是因?yàn)槿澜绲娜藗兌家宰约旱姆绞秸湎B類。你能想象一個沒有鳥鳴的世界嗎?”

Success stories

成功的故事

Swans and other waterfowl have recovered due to conservation efforts and wetland protection. (Photo: Phil Wood [CC BY-ND 2.0]/Flickr)

It wasn't all bad news, as researchers found a few promising bright spots.

這并不全是壞消息，研究人員發(fā)現(xiàn)了一些有希望的亮點(diǎn)。

They said waterfowl, like ducks, geese and swans, have made a "remarkable recovery" over the past 50 years. Researchers credit conservation efforts made by hunters, as well as government funding for wetland protection and restoration.

他們說水禽，像鴨子、鵝和天鵝一樣，在過去的50年里已經(jīng)有了“顯著的恢復(fù)”。研究人員將此歸功于獵人為保護(hù)濕地所做的努力，以及政府為濕地保護(hù)和恢復(fù)提供的資金。

The study also found that the bald eagle has made an amazing comeback since the 1970s, when the pesticide DDT was banned and endangered species legislation began offering protection to the birds.

該研究還發(fā)現(xiàn)，自上世紀(jì)70年代殺蟲劑DDT被禁止、瀕危物種立法開始保護(hù)禿鷹以來，禿鷹已經(jīng)驚人地卷土重來。

"It's a wake-up call that we've lost more than a quarter of our birds in the U.S. and Canada," said coauthor Adam Smith from Environment and Climate Change Canada.

“這是一個警鐘，在美國和加拿大我們已經(jīng)失去了超過四分之一的鳥類，”來自加拿大環(huán)境和氣候變化的共同作者亞當(dāng)·史密斯說。

"But the crisis reaches far beyond our individual borders. Many of the birds that breed in Canadian backyards migrate through or spend the winter in the U.S. and places farther south — from Mexico and the Caribbean to Central and South America. What our birds need now is an historic, hemispheric effort that unites people and organizations with one common goal: bringing our birds back."

但是，這場危機(jī)遠(yuǎn)遠(yuǎn)超出了我們各國的邊界。許多在加拿大后院繁殖的鳥類會遷徙到美國或在更遠(yuǎn)的南部地區(qū)過冬——從墨西哥和加勒比海到中美洲和南美洲。我們的鳥類現(xiàn)在需要的是一項(xiàng)歷史性的半球努力，它將人類和組織團(tuán)結(jié)在一起，實(shí)現(xiàn)一個共同的目標(biāo):把我們的鳥類帶回地球。”