A white sperm whale, a very rare marine animal, was spotted by sailors aboard a Dutch tanker off the coast of Jamaica. They saw the animal on Nov. 29 and its captain, Leo van Toly, recorded a video showing the sperm whale near the water's surface.

After recording it, he sent the video to his sailing partner, Annemarie van den Berg, who is the director of the charity organization SOS Dolfijn for the preservation of whales in the Netherlands. After receiving confirmation from the experts, SOS Dolfijn shared the video on its Facebook page.

Sighting a white sperm whale is a very rare thing

With the sheer size of the ocean, and the fact that we still don't know everything about it, it is very difficult for scientists to say how many white sperm whales there are. This animal is very elusive, and rarely rises to the surface, usually using its deep diving ability to stay deep in the ocean for long periods of time.

"It's easy for a whale to hide, even one that's as long as a school bus," said Shane Gero, a sperm whale expert at Dalhousie University in Canada, "So even if there were a lot of white sperm whales, you just wouldn't see them very often."

The last time the sighting of this sea animal was recorded occurred in 2015 in Sardinia, an Italian island. Besides that one, white sperm whales have also been seen in Dominica in the Caribbean and in the Azores in the Atlantic. Gero says he has a possibility that the sperm whale seen in Jamaica is the same one seen in Dominica.

Besides the sperm whale, there have also been sightings of whales of other species, such as the albino humpback whale called Migaloo that has been seen in Australian waters since 1991, and a pair of killer whales that were seen in Japan in July this year.

Artistic representation of Moby Dick.

White whales have albinism or leucism

The fact that sperm whales and other whales are white is not a natural characteristic of them, but something caused by genetic diseases such as albinism and leucism. Albinism causes the animal can not produce melanin, pigment that gives color to the skin, and leucism affects the production of melanin in some cells, which can cause total or partial loss of color.

Whales with leucism may only have a few white spots, while those with albinism may be completely white. But despite the difference, Gero says it's not possible to differentiate between them without genetic proof.

Some researchers believe that eye color may help differentiate the two conditions, since most albino whales have red eyes, but this is not yet a guarantee. Gero says that the white sperm whale seen in Jamaica may be albino, but there is nothing conclusive about that yet.

Moby Dick and whale hunting

White sperm whales became very famous in Herman Melville's classic novel Moby Dick. In the story, Moby Dick is a huge white sperm whale who is being hunted by Captain Ahab, who has lost his leg to the whale.

As much as it is a very famous novel, critics still debate why Melville left Moby Dick white. Some believe he was criticizing the slave trade, but Gero believes that the whale's coloration is not as important as the way the book shows the relationship between humans and sperm whales.

In 1851, when the book was written, a hunt was going on for whales, especially sperm whales, because they had valuable fats and oils in their bodies, which helped develop new sources of energy and technology. "Before fossil fuels, these whales drove our economy, making our machines run and lighting up our nights. "says Gero.However the hunt forWhales have not been a serious threat to white sperm whales, but current human action such as, oil spills and plastic pollution, presents a risk to the lives of these and many other marine animals. Currently, white sperm whales are listed as animals vulnerable to extinction, even though we do not know how many of them exist in the ocean.