VOA科学技术2023 座头鲸因数量增加而减少"唱歌"求偶（在线收听）

A new study suggests the singing noises made by humpback whales might be a sign of loneliness.

一项新的研究表明，座头鲸发出的歌声可能是孤独的迹象。

Scientists who recorded humpback whale behavior in Australia discovered that fewer whales made the singing noises, also called wailing, as their population grew.

在澳大利亚记录座头鲸行为的科学家发现，随着鲸鱼数量的增加，发出哀号的鲸鱼越来越少。

"Humpback whale song is loud and travels far in the ocean," said marine biologist Rebecca Dunlop of the University of Queensland in Brisbane.

布里斯班昆士兰大学的海洋生物学家丽贝卡·邓洛普说：“座头鲸的歌声很嘹亮，在海洋中能传播很远。”

She has long studied humpback whales and helped lead the new study.

她长期研究座头鲸，并帮助领导了这项新的研究。

Her work has centered on humpbacks that reproduce near Australia's Great Barrier Reef.

她的研究重点是在澳大利亚大堡礁附近繁殖的座头鲸。

Dunlop told The Associated Press she made an unexpected find as whale numbers sharply rose following the end of commercial whaling.

邓洛普告诉美联社，随着商业捕鲸活动的结束，鲸鱼数量急剧增加，她有了一个意想不到的发现。

"It was getting more difficult to actually find singers," she said.

她说：“要真正找到歌手变得越来越难了”。

Dunlop added, "When there were fewer of them, there was a lot of singing – now that there are lots of them, no need to be singing so much."

邓洛普补充说：“当它们数量较少的时候，就会有许多歌声——现在它们数量多了，就没有必要发出那么多歌声了。”

Scientists first began to hear and study the complex songs of the humpback whales in the 1970s.

20世纪70年代，科学家首次听到和研究座头鲸复杂的歌声。

They used underwater microphones to do so.

他们使用水下麦克风来听和研究座头鲸的歌声。

Only male whales sing.

只有雄鲸才会唱歌。

Scientists think the whales sing to seek mates or show power.

科学家认为，鲸鱼唱歌是为了寻找配偶或展示力量。

Eastern Australia's humpback whales came close to disappearing in the 1960s, when their number dropped to around 200.

在20世纪60年代，澳大利亚东部的座头鲸濒临灭绝，当时它们的数量下降到200头左右。

But over time the population began to regrow, climbing to about 27,000 whales by 2015.

但随着时间的推移，鲸鱼的数量开始重新增长，到2015年攀升至约2.7万头。

That number is near estimated pre-whaling levels.

这一数字接近捕鲸前的估值。

As the density of whales increased, their singing behaviors changed.

随着鲸鱼密度的增加，它们的歌唱行为也发生了变化。

While 2 in 10 males made wailing noises in 2004, 10 years later the number had dropped to 1 in 10, Dunlop said.

邓洛普说，2004年，五分之一的雄性座头鲸会发出哀号，而10年后，这一比例下降到了十分之一。

The team's study appeared in a recent issue of Nature Communications Biology.

该团队的研究发表在最近一期的《自然·通讯生物学》上。

Dunlop said she thinks singing played a big part in bringing in mates when populations were severely reduced.

邓洛普说，她认为在种群数量严重减少时，唱歌在吸引配偶方面发挥了很大作用。

"It was hard just to find other whales in the area, because there weren't many," she added.

她补充道：“很难在这个地区找到其他鲸鱼，因为鲸鱼数量并不多”。

When humpbacks live in denser populations, males looking for mates also have to deal with competing whales.

当座头鲸生活在密度更大的种群中时，寻找配偶的雄性鲸鱼也必须与竞争对手打交道。

Dunlop explained the singing noises might bring in other possible mates.

邓洛普解释说，歌声可能会吸引其他可能的配偶。

Boris Worm is an ocean biologist at Canada's Dalhousie University.

鲍里斯·沃姆是加拿大达尔豪斯大学的海洋生物学家。

He was not involved in the research.

他没有参与这项研究。

"As animal populations recover, they change their behavior – they have different constraints," Worm said.

沃姆说：“随着动物数量的恢复，它们会改变自己的行为——它们有不同的限制”。

The research suggests the seas are still noisy with humpback whale sounds.

研究表明，海洋中仍然充斥着座头鲸的歌声。

Many humpbacks seek to bring in mates with a combination of singing and physical movements, the study notes.

研究指出，许多座头鲸试图通过歌唱和肢体动作相结合的方式寻找配偶。

The large increase in the humpback population during the study period provided valuable data about changes in the animals' behavior, said Simon Ingram.

西蒙·英格拉姆说，在研究期间座头鲸数量的大幅增加为研究动物行为的变化提供了宝贵的数据。

He studies humpback whales at the University of Plymouth in Britain.

他在英国普利茅斯大学研究座头鲸。

Ingram said humpback whales must have been singers long before whaling reduced their numbers.

英格拉姆说，座头鲸在捕鲸减少它们的数量之前很久就已经是“歌手”了。

But the new study demonstrates how necessary their complex and beautiful songs were to their survival and recovery, he added.

但他补充说，这项新研究表明，它们复杂而优美的歌声对于它们的生存和恢复是多么必要。

"Clearly singing became incredibly valuable when their numbers were very low," Ingram said.

英格拉姆说：“显然，当它们的数量非常少时，唱歌就变得非常有价值了。”

I'm Bryan Lynn.

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