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Populations of frogs, salamanders and other amphibians¹ are declining around the world—even in protected areas, like U.S. national parks. Ecologists needed a simple method to track the animals’ numbers. Now, researchers have found an effective way to keep tabs on amphibians—using that concert and party favorite: glow sticks. Green glow sticks, to be specific.

青蛙、蝾螈和其他两栖动物在世界各地数量锐减，甚至在美国国家公园等保护区也出现这种状况。 生态学家需要一个简单方法来跟踪动物数量变化情况。现在，研究人员已经找到了一种有效方法来监视两栖动物——发光棒(音乐会和派对最喜欢的物品)。 具体来说是绿色的发光棒。

“What we do know is that their eyes are particularly sensitive to green light.”David Munoz, a PhD candidate in the ecology program at Penn State University.To test the idea, Munoz and colleagues set up minnow traps with and without glow sticks at a dozen vernal pools in Centre County, Pennsylvania. The critters gather at the pools to breed.

“我们知道，动物眼睛对绿光特别敏感。”宾夕法尼亚州立大学生态学专业的博士候选人David Munoz为了测试这个想法，他和的同事们设置了带有和没有荧光棒的捕蝇器，他们在宾夕法尼亚州中心县的十几个春季水池里进行了测试，这些水池是生物聚集和繁殖的良好场所。

For a month, they trapped and tracked numbers of the Jefferson salamander, the Spotted² Salamander, the Wood Frog and the Eastern Red-spotted newt. “Right before we left for the day, around 4pm, we’d activate³ the glow stick and hang it on the little minnow trap, come back the next day to see what we got.”

一个月后，他们对蝾螈、斑点蝾螈、木蛙和东方红点蝾螈的数量进行了追踪研究。“在我们离开的那一天的下午四点左右，我们会启动发光棒，挂在小鱼圈上，第二天会回来看看得到了什么。

Traps with glow sticks were vastly more productive. “We were really surprised by how strong of an effect our glow sticks had on our captures. So, by just putting a glow stick in one of these minnow traps we increased the capture rates for our spotted salamanders and our Jefferson salamanders between on average two to four times.” And for the Eastern Red-spotted newt, the glow stick traps lured⁴ six times as many.

带有荧光棒的陷阱是非常有作用的。“我们真的很惊讶，发光棒对我们的拍摄效果很有帮助。 所以，只要把一根发光棒放在其中的一个小陷阱中，就可以提高蝾螈的捕获率，大约平均两到四倍。“而东方红点蝾螈则引诱发光棒陷阱多达六倍。

“You know, these salamanders and these amphibians are going to these sites to breed. And so what are they looking for? They’re looking for other individuals…and so what we think is that the glow stick is either making the movement of other salamanders more apparent, or it's potentially just a simple visual cue…their eyes are sensitive to this type of light, so they might be attracted to it.”

“这些蝾螈和两栖动物正在去这些地方进行繁殖。那么它们在寻找什么呢?它们正在寻找其他个体...所以我们认为，发光棒要么让其他蝾螈的运动更明显，要么可能只是一个简单的视觉提示...他们的眼睛对这种类型的光非常敏感，所以可能会被它吸引。”

Regardless of the reason, Munoz hopes his team’s glowing discovery will benefit amphibians. “In order to help manage those species, and help bring them back, or reverse those declines, we need to understand what’s causing those declines. And the way we do that is by monitoring populations.”

不管原因如何，Munoz希望他的团队的这一发现将有利于两栖动物。“为了帮助管理这些物种，并帮助恢复这些物种数量，或者扭转这样的下滑趋势，我们需要了解造成这些物种下降的原因。而我们这样做的方式是通过监测种群数量变化来达到目的。”

Another nice thing about glow sticks: they’re cheap. “It gives scientists a new tool, and essentially⁵ a better tool to help achieve that monitoring on a cost effective basis.”

发光棒的另一个好处是：它们很便宜。“它为科学家们提供了一个新的工具，而且从本质上讲是一个更好的工具，它可以帮助实现成本效益的监测。”