Building a road through wilderness certainly has a visible effect on local flora and fauna - you're physically paving over a slice of what was once habitat. But roads have less obvious effects, too. Like the introduction of traffic noise, which also takes a toll. You can see an oil spill but you can't see you know a traffic noise spill. So convincing people that it's important I think is a little more difficult.
在野外建造一条公路对当地的动植物肯定会有显而易见的影响——公路直接铺设在栖息地上。但公路也会带来不太明显的影响。比如交通噪音的引入，这同样会产生负面影响。你能看到原油泄漏，但你看不到交通噪音。所以，我觉得让人们相信这很重要会更困难。
Heidi Ware, an ornithologist at the Intermountain Bird Observatory in Boise, Idaho. She and her colleagues studied the reactions by birds to the sounds of vehicles. And they did it without paving the great outdoors. Instead, they mounted 15 pairs of speakers on Douglas fir trees, along a ridge near Boise, and played traffic noise. They thus created what they call a "phantom road" through the wilderness, which boosted local noise levels about 10 decibels higher than those in the surrounding forest.
海蒂·韦尔，爱达荷州博伊斯山间鸟类观察站的鸟类学家。她和同事研究了鸟类对汽车声音的反应。不过，他们不是在野外铺设公路，而是在博伊斯附近一条山脊上的花旗松树上安装了15对喇叭。这样，他们就在野外制造了一条他们所说的“幽灵公路”。那里的噪声水平比周围树林增强了大概10分贝。
Turns out just the sounds of traffic scared away a third of the area's usual avian visitors, and cut species diversity too. And birds of multiple species weren't able to pack on as much fat to fuel their migrations, when they were forced to dine to the soundtrack of traffic.
结果显示，交通噪声吓跑了三分之一该地区的鸟类常客，也降低了物种多样性。并且，在被迫听着交通噪声进食之后，许多鸟类都无法囤积足够多的脂肪来支撑它们迁徙。
Follow-up experiments in the lab found that, when it's noisy, birds spend a lot less time head down, pecking at food, and a lot more time scanning their surroundings. You can imagine if you take away that ability to listen for predators, birds need to compensate by looking around more. It sort of wastes their time, right? So instead of spending their time eating they have to spend their time doing other things. The study is in the journal Proceedings of the National Academy of Sciences.
实验室里的后续实验发现，当很吵的时候，鸟儿们花在低头啄食的时间少了很多，而花在观察周围环境的时间却多了很多。你可以想象，如果把监听捕食者的能力拿走了，鸟儿们就要通过更多观察周围来弥补这个能力的缺失。这其实会浪费它们的时间。它们没有把时间花在进食上，而是花在了其他事情上。该研究发表在《美国科学院论文集》。
Ware says Yosemite, Glacier and Rocky Mountain National Parks all have roads that are busy enough to produce these effects. And, short of closing park roads to traffic, she says things like rubberized asphalt and lower speed limits could help cut the noise. Glacier National Park is going to put up signs, that instead of showing your speed and preventing people from speeding, it's gonna show how loud their car is on the road. Which, hopefully, will continue to encourage wilderness lovers to leave no trace - visible or audible.
韦尔称约塞米蒂、冰河和落基山国家公园都有繁忙的公路能够产生这样的影响。除了关闭公园里的公路之外，她说，铺设橡胶沥青和降低限速等等都能帮助减少噪音。冰河国家公园将设置路标，显示你的车在路上有多吵，而不仅仅显示车速，防止人们超速。希望这能继续鼓励喜欢野外的人在开车路过时不留痕迹——不管是看得到的还是听得到的痕迹。
