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Highway Crossings Protect Migrating Pronghorns--and Motorists

Ever hear of the pronghorn antelope¹ in the American west? Well, it’s not really an antelope—it’s actually more closely related to giraffes than to true antelopes². And the last known migration³ of pronghorns occurs between Grand Teton National Park and the upper Green River Basin in western Wyoming. The so-called "path of the pronghorn" stretches more than 150 miles and is one of the longest mammal migration corridors that remain in North America.

听说过美国西部的叉角羚吗?嗯，这并不是羚羊——实际上它与长颈鹿的关系比与真正的羚羊更密切。已知的叉角羚最后一次迁徙，发生在大提顿国家公园和怀俄明州西部上绿河流域之间。所谓的“叉角羚之路”绵延150多英里，是北美现存最长的哺乳动物迁徙走廊之一。

That stretch is also the only federally designated wildlife migration corridor. The trouble is that the corridor intersects with roads and fences, presenting obvious problems to the animals. So Wyoming officials built eight wildlife crossings along some 12 miles of U.S. highway 191: two overpasses⁴ and six underpasses. But having a crossing doesn't mean wildlife will use it. So researchers decided⁵ to assess the impacts of the $9.7 million investment.

该区域也是联邦唯一指定的野生动物迁徙走廊。问题是，这条走廊与道路和栅栏交叉，给动物们带来了明显的问题。因此，怀俄明州的官员在美国191号高速公路12英里处修建了8个野生动物通道:2个立交桥和6个地下通道。但是有个十字路口并不意味着，野生动物会使用它。因此，研究人员决定评估这970万美元投资的影响。

"We're out in the field, on spotting scopes, watching these animals as they're approaching brand-new structures. This was a perfect setting, because we had been studying these pronghorn, these animals on their long-distance migration, for about a decade."Wildlife Conservation Society biologist Renee Seidler, now at the Idaho Department of Fish and Game.

“我们在野外观察，观察这些动物，看着它们接近崭新的结构。这是一个完美的环境，因为我们研究这些叉角羚，这些长途迁徙的动物，已经有十年了。野生动物保护协会的生物学家Renee Seidler说。

She focused her observations on an area called Trapper's Point. Twice a year, between one and two thousand pronghorn, along with some three thousand mule⁶ deer pass through the area. Archaeological evidence indicates that pronghorn have been moving through Trapper's Point for at least six thousand years. But now they have to contend with highways and fast cars. Before the wildlife crossings were built, the 12 miles of the two-lane highway 191 saw an average of 85 animal-vehicle collisions each year.

她的观察集中在一个叫做“猎人点”的区域。每年两次，大约有一千只叉角羚和三千多只叉角羚穿过这个地区。考古证据表明，叉角羚已经在猎人的穴居地活动了至少6000年。但现在他们不得不与高速公路和高速汽车竞争。在建立野生动物通道之前，191号双线高速公路长达12英里，平均每年发生85起动物车辆相撞事故。

"We looked at how many times an animal would attempt to use the crossing structure before they were able to successfully get to the other side. And the success rate of crossing within that definition increased over time."

“我们观察了一只动物在成功到达另一边之前会尝试多少次穿越结构。”随着时间的推移，在这个定义范围内交叉的成功率增加了。

In other words, the pronghorn eventually learned to use the crossing. And that's good news for motorists too: Seidler found a 70 percent reduction in wildlife-vehicle collisions. The results are in the journal Global Ecology and Conservation.

换句话说，叉角羚最终学会了穿越。这对开车的人来说也是个好消息:Seidler发现野生动物车辆碰撞事故减少了70%。研究结果发表在《全球生态与保护》杂志上。

Four years after the crossings were built, every single pronghorn successfully used them to avoid the highway and complete their migration."These are migrations⁷ that have been compared to migrations on the Serengeti in Africa. These are stellar, long-distance migrations, and I think as a culture we should hold innate⁸ pride in that… Wyoming did a really good thing when they put in these crossing structures and fences, so that these animals can continue their migration."

在十字路口建成四年后，每只叉角羚都成功地避开了高速公路，完成了迁徙。这些移民被比作非洲塞伦盖蒂平原上的移民。他说:“我认为这是一种非常重要的迁徙方式。这是一种明星级的长距离迁徙。我认为，作为一种文化，我们应该对这一点保持固有的自豪感。怀俄明州做了一件很好的事情，他们在这里设置了这些交叉结构和栅栏，这样这些动物就可以继续迁徙了。”