"I've been [studying turtles] for a long time, and I don't think anyone's ever seen this," sea turtle expert Alexander Gaos tells National Geographic. "This is really quite amazing." Gaos is referring to video footage showing a hawksbill sea turtle glowing neon red and green, looking like a swimming rave or, in the words of marine biologist David Gruber, a gliding spaceship. The turtle is the first-known example of biofluorescence in reptiles. The ability to reflect blue light from the ocean and reflect it back as a different color has previously been seen in coral, fish, sharks, and more. And previously only coral was known to glow in more than one color, according to the Christian Science Monitor.
Gruber was attempting to film biofluorescence in sharks and coral in the Solomon Islands in July when the glowing turtle "came out of nowhere," National Geographic reports. “I followed it for a few minutes, and then it dove down a deep coral wall," Gruber tells ABC News. "I decided to leave it alone as it had already divulged its secret." Gruber, who found more examples of biofluorescence in local captive hawksbills, isn't sure why these sea turtles glow or if hawksbills elsewhere do, too. They're one of the rarest species on the planet, having been hunted nearly to extinction to make tortoiseshell products, and that makes them hard to study, according to the Monitor. (Read more discoveries stories.)