Of all the creatures on the planet, the narwhal is one of the strangest looking. It's a whale which has a large protruding tusk coming out of its head; that's how it got its nickname, the unicorn of the sea. They live in the Arctic Ocean off the coast of Canada, Russia and East Greenland. However, experts say some populations of narwhal could be extinct by 2025, and it's all because of noise pollution. 

在地球上的所有生物中，独角鲸是长相最奇怪的一种。这是一头鲸鱼，头上长着一根巨大的、突出的獠牙。这就是它的绰号“海上独角兽”的由来。它们生活在加拿大、俄罗斯和东格陵兰海岸附近的北冰洋。然而，专家表示，到 2025 年，一些独角鲸种群可能会灭绝，而这一切都是因为噪音污染。 

Narwhals rely on echolocation, which they use to find food and navigate their surroundings. The animal produces a sound wave which bounces off an object. They pick this reflected sound up through their lower jaw, and information on features like size and speed passes to their ears. 

独角鲸依靠回声定位来寻找食物和导航周围环境。动物产生一种从物体上反射回来的声波。它们通过下颌拾取反射的声音，并将有关尺寸和速度等特征的信息传递到它们的耳朵。 

However, increase in human marine activity, as well as climate change, has resulted in the Arctic Ocean becoming noisier, which means it's more difficult for narwhals to rely on sound. Susanna Blackwell, who studies the effects of underwater noise on marine animals, told the BBC that there is noisier activity in the Arctic Ocean than ever because, as sea ice melts, new navigation routes are opening. And while icebergs breaking and creaking have been part of the ocean soundscape for hundreds of years, man-made noise is much harder for animals to adapt to, particularly as these changes are so sudden. 

然而，人类海洋活动的增加以及气候变化导致北冰洋变得更加嘈杂，这意味着独角鲸更难以依赖声音。研究水下噪音对海洋动物影响的苏珊娜·布莱克韦尔（Susanna Blackwell）告诉英国广播公司（BBC），北冰洋的噪音活动比以往任何时候都更加激烈，因为随着海冰融化，新的航行路线正在开辟。虽然冰山破裂和吱吱作响数百年来一直是海洋声景的一部分，但人造噪音对动物来说更难以适应，特别是因为这些变化是如此突然。 

Research published in Science Advances in 2023 recorded the reactions of narwhals to the simulated noises of oil expeditions made by a patrol vessel. The scientists tagged and tracked the creatures and found that, on hearing these sounds, they ended deep dives and stopped clicking, the echolocation signal they use for finding food underwater. This is the same reaction narwhals have to orcas, who hunt them, meaning human-made noise could trigger the creature's 'threat button'. 

2023 年《科学进展》上发表的研究记录了独角鲸对巡逻船模拟石油探险噪音的反应。科学家们对这些生物进行了标记和追踪，结果发现，当它们听到这些声音时，它们就会停止深潜并停止滴答声，这是它们用来在水下寻找食物的回声定位信号。这与独角鲸对猎杀它们的逆戟鲸的反应相同，这意味着人为噪音可能会触发该生物的“威胁按钮”。 

So, what can we do? Charlotte Findlay, a postdoctoral fellow at Aarhus University, says "noise is actually quite easy to solve. We need to either turn it off or turn it down." 

所以，我们能做些什么？奥胡斯大学博士后研究员夏洛特·芬德利表示：“噪音实际上很容易解决。我们需要要么将其关闭，要么将其调低。” 

词汇表

narwhal 一角鲸
protruding 突出的，鼓出来的
tusk （动物的）长牙
unicorn of the sea 海洋独角兽
extinct 灭绝的
echolocation （动物的）回声定位
bounce off 从…反弹
lower jaw 下颌骨
marine activity 海洋活动
marine animals 海洋动物
navigation route 航线
soundscape 声景
adapt to 适应
tag 标记，给动物植入定位芯片
track 跟踪
deep dive 深潜
click （鲸鱼等动物）发出短而尖的声音
orca 虎鲸
hunt 捕猎