研究人员曾认为南极海域无鲨鱼 却意外拍到其踪迹


2026年2月18日 / 美国东部时间凌晨4:51 / 美联社

澳大利亚墨尔本— 一条外形笨拙如桶的睡鲨在昏暗无光的海底深处悠然游弋,阳光无法穿透如此深的海域,这一景象令人意外。

西澳大学研究员艾伦·贾米森本周表示,在此之前,许多专家认为南极寒冷水域中不存在鲨鱼,直到这条睡鲨小心翼翼地短暂出现在摄像机镜头前。这条拍摄于2025年1月的鲨鱼体型庞大,估计长度在10至13英尺之间。

这张由视频截图制作并经西澳大学发布的图片显示,2025年1月,一条睡鲨在南极海域游入摄像机镜头范围。图片来源:Minderoo-UWA深海研究中心、Inkfish、Kelpie地球科学公司(美联社)

“我们下潜时本没指望看到鲨鱼,因为通常认为南极不会有鲨鱼,”贾米森说,“而且这绝非小型鲨鱼,它体型巨大,就像个‘铁桶’。”

Minderoo-UWA深海研究中心的摄像机位于南极半岛附近的南设得兰群岛海域,该中心致力于研究全球海洋最深处的生物。这一区域位于南极圈以南,属于南极洋(Southern Ocean)范围,其定义为南纬60度以南的海域。

该中心周三允许美联社发布这些图像。

这条鲨鱼在1608英尺深的海域活动,水温接近冰点,仅34.29华氏度。

海床上,一条鳐鱼静止不动,似乎未受鲨鱼经过的影响。鳐鱼与鲨鱼同属软骨鱼类,其分布范围已被科学家证实可达南极海域,因此并不意外。

贾米森称,西澳大学研究中心成立时,他查阅了所有记录,未发现南极洋有其他鲨鱼的记录。

独立于该研究中心的查尔斯达尔文大学保护生物学家彼得·凯恩也表示,此前从未有鲨鱼在如此南纬地区被记录。

凯恩指出,气候变化和海洋变暖可能正促使鲨鱼向南半球更寒冷水域迁移,但由于南极地区偏远,关于其分布变化的数据十分有限。

“睡鲨行动缓慢,或许早已在南极活动而无人察觉,”凯恩说,“这条鲨鱼在正确的地点,摄像机也在正确的位置,拍到了珍贵的影像,这意义重大。”

贾米森表示,南极洋的睡鲨种群可能十分稀疏,难以被人类发现。

拍摄到的鲨鱼保持在约1640英尺深度游动,海床向更深水域延伸。鲨鱼选择这一深度是因为这里是多层海水(从海面到海底依次递减温度)中最温暖的一层。

南极洋因海水密度差异形成明显分层:底部寒冷且密度大的海水与上层融化冰原带来的淡水难以混合,导致从海面到约3280英尺深度形成稳定的垂直分层结构。

贾米森推测,其他南极鲨鱼可能也栖息在同一深度,以鲸鱼、巨型鱿鱼及其他海洋生物的尸体为食,这些生物死亡后会沉至海底。

南极海域特定深度的研究摄像机十分稀少,且仅在南半球夏季(12月至2月)期间运行。

“一年中其余75%的时间无人观测,这也是为何我们偶尔会有此类意外发现,”贾米森解释道。

Researchers didn’t think there were sharks in Antarctica waters. Then one was caught on camera.

February 18, 2026 / 4:51 AM EST / AP

Melbourne, Australia— An ungainly barrel of a shark cruising languidly over a barren seabed far too deep for the sun’s rays to illuminate was an unexpected sight.

Many experts had thought sharks didn’t exist in the frigid waters of Antarctica before this sleeper shark lumbered warily and briefly into the spotlight of a video camera, researcher Alan Jamieson said this week. The shark, filmed in January 2025, was a substantial specimen with an estimated length of between 10 and 13 feet.

In this image made from video and released by the University of Western Australia, a sleeper shark swims into the spotlight of a video camera in Antarctica in January 2025. Minderoo-UWA Deep-Sea Research Centre, Inkfish, Kelpie Geoscience via AP

“We went down there not expecting to see sharks because there’s a general rule of thumb that you don’t get sharks in Antarctica,” Jamieson said. “And it’s not even a little one either. It’s a hunk of a shark. These things are tanks,” he added.

The camera operated by the Minderoo-UWA Deep-Sea Research Centre, which investigates life in the deepest parts of the world’s oceans, was positioned off the South Shetland Islands near the Antarctic Peninsula. That’s well inside the boundaries of the Antarctic Ocean, also known as the Southern Ocean, which is defined as below the 60-degree south latitude line.

The center on Wednesday gave The Associated Press permission to publish the images.

The shark was 1,608 feet deep, where the water temperature was a near-freezing 34.29 degrees Fahrenheit.

A skate appears in frame motionless on the seabed, seemingly unperturbed by the passing shark. The skate, a shark relative that looks like a stingray, was no surprise since scientists already knew their range extended that far south.

Jamieson, the founding director of the University of Western Australia-based research center, said he couldn’t find any record of another shark found in the Antarctic Ocean.

Peter Kyne, a Charles Darwin University conservation biologist independent of the research center, agreed that a shark had never before been recorded so far south.

Climate change and warming oceans could potentially be driving sharks to the Southern Hemisphere’s colder waters, but there was limited data on range changes near Antarctica because of the region’s remoteness, Kyne said.

The slow-moving sleeper sharks could have long been in Antarctica without anyone noticing, he said.

“This is great. The shark was in the right place, the camera was in the right place and they got this great footage,” Kyne said. “It’s quite significant.”

The sleeper shark population in the Antarctic Ocean was likely sparse and difficult for humans to detect, Jamieson said.

The photographed shark was maintaining a depth of around 1,640 feet along a seabed that sloped into much deeper water. The shark maintained that depth because that was the warmest layer of several water layers stacked upon each other to the surface, Jamieson said.

The Antarctic Ocean is heavily layered, or stratified, to a depth of around 3,280 feet because of conflicting properties including colder, denser water from below not readily mixing with fresh water running off melting ice from above.

Jamieson expects other Antarctic sharks live at the same depth, feeding on the carcasses of whales, giant squids and other marine creatures that die and sink to the bottom.

There are few research cameras positioned at that specific depth in Antarctic waters. Those that are can only operate during the Southern Hemisphere summer months, from December through February.

“The other 75% of the year, no one’s looking at all. And so this is why, I think, we occasionally come across these surprises,” Jamieson said.

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