A Japanese researcher says he has taught a beluga whale to "talk" by using sounds to identify three different objects, offering hope that humans may one day be able to hold conversations with sea mammals.

Nack, a whale at the Kamogawa Sea World marine¹ park near Tokyo, emits a short, high-pitched sound when he sees a swimming fin², a long, high-pitched sound when he sees goggles³ and a short, low-pitched sound when he sees a bucket.

He correctly chooses the right object when the three sounds are played back to him.

Tokai University professor Tsukasa Murayama started training Nack after he became dissatisfied with hand-signals currently⁴ used to communicate with dolphins and whales.

"I have always wanted to talk to whales, and as I thought more and more about it, I realized that they already communicated through sound," he told reporters.

"That is why I thought I could train them to name certain items using sounds they already make."

Murayama said he hoped one day to train whales to express their feelings in a way that humans could understand.

"It would be great if they would be able to tell us not only of their likes and dislikes but also their desires, like whether they are hungry or if their backs are itchy. So the next step would be to teach them a wider range of vocabulary," he added.

However, to expand communication, Murayama said humans needed to use special equipment to produce and detect ultrasonic⁵ sounds.

"At the moment we are only using limited sounds audible for us among their wide sound range. But whales communicate better through ultrasonic sounds than through human-audible sounds, especially underwater," he explained.

Japan has come under growing pressure from international environmental groups to put an end to whale hunts, which they say are cruel and violate⁶ a 1986 global moratorium⁷ on commercial whaling.

Japan considers whaling to be a cultural tradition which it says it only undertakes for scientific research.

Meat from the hunts is available in Japanese supermarkets and restaurants, although appetite for what is now a delicacy⁸ is fading.

 日本一位科研人员日前称，他成功教会了一头白鲸用声音“说出”三个不同的物体。这一研究成果为人类有朝一日与海洋哺乳动物对话带来了希望。

这头会说话的白鲸名叫“纳克”，家住东京附近的鸭川海洋世界。每当纳克看见游动的鳍状物时，它会发出一阵短高音；当它看到潜水镜时，会发出长高音；而看到水桶时，它又会发出一声短低音。

之后再将这三种声音播放给它听时，它也能正确地识别出相应的物品。

东海大学的村上司教授对于用手势与海豚和鲸鱼交流并不满足，于是他开始教纳克“说话”。

他在接受记者采访时说：“我一直希望能与鲸鱼说话，而随着对这个问题思考的深入，我意识到其实它们已经在用声音进行交流，这也是为什么我相信我能教会它们用已掌握的声音‘说出’一些不同的物体。”

村上教授说，他希望有朝一日能教会鲸鱼用人类可理解的方式来表达它们的想法和感情。

他说：“如果它们可以告诉我们它们的好恶以及它们想要什么——比如它们是不是饿了，是不是背痒了，那将是一件了不起的事情。所以下一步的任务是要拓宽它们的词汇量。”

然而，据村上教授介绍，如果要加深人与鲸之间的这种“对话”，人类就需要使用特殊的仪器去制造和探测超声波。

他解释说：“鲸鱼的叫声音区很广，而目前我们只能通过人耳可听到的声音与它们交流。但与人耳可听见的声音相比，鲸鱼更‘擅长’用超声波交流，尤其是在水下。”

近年来，国际环保组织一直在向日本施压，要求其停止捕鲸活动。国际环保组织指责日本的捕鲸行为不仅残忍，而且违反了1986年的国际反商业捕鲸条例。

而日本则认为，捕鲸是他们的一个文化传统，并称被捕捞的鲸鱼仅用于科学研究。

尽管日本人对鲸鱼肉的兴趣已逐渐减退，但如今这一美味在日本的超市和餐馆依然可见。