The first measurement of the heart rate of the blue whale

US scientists on November 25 said they had measured the heart rate of an adult blue whale with a high-tech ECG recorder.

Using an electrocardiograph with four endpoints attached to the back of a 22-meter-long blue whale in Monterey Bay, off the California coast, scientists measured the heartbeat of the largest animal on the planet for the first time. They help us better understand their physiology.

The animal's maximum heart rate reaches 37 beats per minute by the time it rises to the surface to breathe.

The recorded data shocked the team at a time when the blue whale's heart rate dropped to just two beats per minute, 30-50% lower than previously predicted. The animal's maximum heart rate reaches 37 beats per minute by the time it rises to the surface to breathe. The deeper the dive to feed the whale's heart rate, the lower it is, according to the Proceedings of the National Academy of Science magazine .

The blue whale is the largest "all time" animal when it can grow to a length of over 30m and weighs 180 tons. In general, the larger the animal, the lower the heart rate, which reduces the amount of work the heart has to do to distribute blood around the body.

By comparison, human heart rates range from 60 to 100 beats per minute, while in shrews, the world's smallest mammals by mass, their heart rate is thousands of beats per minute.

Besides the heart rate, the team also tracks the dive time of the whale. Data show that the animal did not spend more than four minutes on the water to get oxygen. Its longest dive lasted 16 and a half minutes.

The information on the behavior and physiology of blue whales is very important in the conservation of this endangered animal. The research was conducted by scientists from Stanford University, Cascadia Research Laboratory, Scripps Institution of Oceanography and University of California Santa Cruz.

The team mounts a heart rate monitor on the back of a whale in Monterey Bay.(Video: VOA).

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