An incredibly rare all-white orca whale has been spotted off the coast of Alaska.
The young male has been named Tl'uk, which is the Coast Salish word for 'moon' on account of his incredible white/grey colouring, reminiscent of the moon.
The juvenile killer whale was spotted with two other adults near the Kuiu and Kupreanof Islands, off the west of Petersburg, Alaska on August 7.
The spectacular sight was witnesses by some extremely lucky whale watchers about a charter boat organised by Alaska Sea Adventures.
The owner Dennis Rogers said that Tl'uk's colour makes him easier to spot, even when he goes under the water.
Speaking to local radio station KFSK, Rogers explained: "When [orcas go] underwater, usually they disappear and typically are very hard to follow,
"But having a white one under the water, you could see him an easy ten feet below the surface, this big white shape moving along there."
Aboard the boat at then time was first mate - and marine biology student from the University of Alaska Fairbanks - Stephanie Hayes.
She's the one who managed to capture the photos and video of the incredible animal.
Hayes explained: "I saw kind of a glow under the water and I'm thinking, wow that's an awfully white killer whale, that's doing something funny,
"And no, it was just genuinely the white killer whale. And it popped up and you could hear an audible gasp from everybody on the bow, going 'oh my gosh what are we seeing here?'.
"It was really incredible."
As well as being all-white, the rare whale also has some very easily distinguishable marking that make him pretty easy to identify when spotted.
Even though he's been given the name Tl'uk, his official name is T46-B1B.
Being a different colour could potentially present challenges for Tl'uk, but - according to the experts aboard the boat, anyway - he's getting along just fine.
Hayes continued: "He looked like a healthy member of the pod and was successfully hunting seals, which is excellent,"
Animals such as Tl'uk, that aren't completely albino -a fact that's indicated by the fact that he's not completely white with pink eyes - are known as leucistic.
It's a bit of a catch-all term that means they lack pigment, or have white, light, or blotchy skin.
Either way, it's incredibly unusual, and there are less than ten leucistic whales known to be alive at the moment.
Featured Image Credit: Stephanie HayesTopics: World News, Interesting, US News, Animals