ANCHORAGE, Alaska (Reuters) - For the first time, scientists have recorded singing by one of the rarest whales on Earth, and it just might be looking for a date.

A North Pacific right whale is seen in the North Pacific Ocean, believed to be one of less than 50 in U.S. waters, in this undated photo. Courtesy Marine Mammal Commission/Handout via REUTERS

The crooning comes from a possibly lovelorn North Pacific right whale and its song was documented by researchers in the Bering Sea off Alaska’s coast, and announced on Wednesday by the National Oceanic and Atmospheric Administration.

The song may not be a greatest hit, but is classified by marine biologists as an underwater call using a distinct pattern of sounds.

And it is the scientists’ best guess that this serenade of the seas is a mating call from a lonely aquatic mammal.

Scientists surveying endangered marine mammal populations first heard the tune in 2010 but could not be sure what kind of whale was singing, said Jessica Crance, of NOAA’s Alaska Fisheries Science Center.

At the time, the researchers were traveling in thick fog and could not see the animal, she said.

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But scientists figured out it was indeed a right whale after analysis of a lot of collected acoustical data, followed by a specific sighting during a 2017 marine-mammal research cruise, Crance said.

That year, “We saw the whale that was singing,” she said.

The right whale’s caroling is described in a study published in the current issue of the Journal of the Acoustical Society of America, and is the first confirmed song from any right whale population.

This history-making discovery sheds light on behavior of one of the planet’s most elusive marine animals, NOAA said.

While this is the first known tune, right whales are not mute. They are known to be chatty by making “gunshot” sounds.

What made this newly-recorded noise a song was its repeated pattern, “timing in between gunshots and the number of gunshots,” she said.

The singing whale spotted in 2017 was a male, and is in the tiny population where dates are hard to find.

There are only about 30 whales in this population and males outnumber females by a 2-to-1 or 3-to-1 ratio, Crance said.

Right whales were hunted nearly to extinction by commercial whalers. The species was named “right whales” in whaler lingo of old, because they were the right whales to hunt. They are slow, easy targets and hold so much body fat that they float when killed, according to NOAA.

“It’s really exciting whenever we see one. Every single sighting is very, very important,” she said.