加利福尼亚蓝鲸歌唱的秘密

This is Scientific American's 60-second Science, I'm Susanne Bard.

这里是科学美国人——60秒科学系列，我是苏珊娜·巴德。

Blue whales off California’s coast sing at night—until it’s time to start migrating, and they switch to daytime song.

加利福尼亚海岸附近的蓝鲸在夜间唱歌——直到开始迁徙时，它们才会在白天唱歌。

During the summer, blue whales in the Northeastern Pacific spend their days feeding on massive amounts of tiny plankton called krill.

在夏季，东北太平洋的蓝鲸以大量称为磷虾的微小浮游生物为食。

In fact, krill is all they eat.

事实上，他们以吃磷虾为食。

“It really is remarkable that such a small animal is able to sustain the largest life form that’s ever existed on this planet.”

“如此小的动物能够维持这个星球上有史以来最大的生命形式，这真的很了不起。”

Stanford University marine ecologist Will Oestreich.

斯坦福大学海洋生态学家威廉·奥斯特赖希。

“And to maintain themselves at that body size, they have pretty extreme feeding habits.”

“为了保持这样的体型，它们有非常极端的进食习惯。”

A blue whale consumes many tons of krill every day.

一头蓝鲸每天要消耗数吨磷虾。

Eating keeps the ocean giants occupied during daylight hours, when they dive hundreds of feet below the surface, where krill congregate in dense swarms.

当蓝鲸白天潜入地表以下数百英尺，这里是磷虾密集聚集的地方，进食使海洋巨兽忙得不可开交。

But at night, when their prey disperse, the whales start to sing.

但是到了晚上，当它们的猎物散去时，鲸鱼开始唱歌。

“And they’ll sing for 10, 12 hours straight.”

“他们会连续唱 10、12 个小时。”

The song you just heard was sped up 10 times.

你刚刚听到的歌曲被加速了 10 倍。

“Which brings the sound up more into human hearing range.”

“这使声音更接近人类的听觉范围。”

Speeding up the song enables researchers to more easily study whales’ deep and resonant songs, which can be heard by other whales across vast distances in the ocean.

加快歌声速度使研究人员能够更轻松地研究鲸鱼发出的深沉而嘹亮的歌声，这些歌声可以被海洋中相隔很远的其他鲸鱼听到。

“It’s very likely that song in blue whales is related to some sort of reproductive function, whether that’s attracting a mate or warding off other males.”

“蓝鲸的歌声很可能与某种生殖功能有关，无论是吸引配偶还是躲避其他雄性。”

Since 2015, the Monterey Bay Aquarium Research Institute has been recording the songs of blue whales with an underwater microphone attached to the seafloor.

自 2015 年以来，蒙特雷湾水族馆研究所一直在用连接在海底的水下麦克风录制蓝鲸的歌声。

“24/7, 365 days a year, giving an audio feed of all of the sounds being produced in and around Monter.

“一年365天，每天24小时，每天24小时，提供Monter及其周边所有声音的音频信息。 ”

When Oestreich and his team analyzed the blue whales’ singing behavior across seasons, they noticed an unusual pattern.

当奥斯特赖希和他的团队分析蓝鲸跨季节的歌唱行为时，他们注意到了一种不寻常的模式。

As summer gave way to fall and winter, the whales changed when they sang.

随着夏天让位于秋天和冬天，鲸鱼在唱歌时发生了变化。

“There was more song during the daytime than during the nighttime.”

“白天的歌比晚上多。”

To learn more, the scientists tagged individual whales to keep tabs on both their feeding and singing behavior.

为了了解更多信息，科学家们对个别鲸鱼进行了标记，以密切关注它们的进食和歌唱行为。

As summer krill concentrations wane, the whales begin a long southward migration to their breeding grounds off the coast of Mexico and Central America.

随着夏季磷虾密度的下降，鲸鱼开始向南迁移到墨西哥和中美洲海岸附近的繁殖地。

“Once they start migrating, feeding at depth isn’t really a part of the equation anymore.

“一旦它们开始迁徙，在深海觅食就不再是问题的一部分了。 ”

So they switch their primary time of song production to the daytime.”

因此，他们将主要的歌曲制作时间改为白天。”

Knowing when to leave is crucial.

知道什么时候离开很重要。

“It’s really critical that the timing of this transition from feeding to migration be synched with other things happening in their habitats.”

“从进食到迁徙的过渡时间与栖息地中发生的其他事情同步，这一点非常重要。”

The researchers think the seasonal change in singing patterns signals the start of migration, which means ...

研究人员认为，歌唱模式的季节性变化标志着迁移的开始，这意味着......

“We’re now able to determine when the population has switched from feeding to migration.”

“我们现在能够确定人口何时从进食转变为迁徙。”

The study is in the journal Current Biology. [William K. Oestreich et al., Animal-borne metrics enable acoustic detection of blue whale migration].

该研究发表在《当代生物学》杂志上。 [威廉·奥斯特赖希等人，动物传播指标使蓝鲸迁徙的声学检测成为可能]。

The blue whale song recording is courtesy of John Ryan and the Monterey Bay Aquarium Research Institute.

蓝鲸歌曲录音由 约翰·瑞安 和蒙特雷湾水族馆研究所提供。

Blue whales are endangered, but being able to monitor what they’re up to in real time could be a boon to conservation efforts—if we’re willing to listen.

蓝鲸濒临灭绝，但如果我们愿意倾听的话，能够实时监控它们的活动可能对保护工作大有裨益。

Thanks for listening for Scientific American's 60-second Science. I'm Susanne Bard.

谢谢大家收听科学美国人——60秒科学。我是苏珊娜·巴德。