Watch: A Myth? A Leaf? Aquarium Displays Rare Sea Dragons

The Birch Aquarium in San Diego, California, has built what is believed to be the world's largest habitat for two types of surreal sea dragons. You could be forgiven for thinking though, that the aquarium houses nothing but plants at first glance - so closely do these sea dragons resemble leaves and weeds.

There are only two types of sea dragons - lesser cousins to their more famous sea horses. These sea dragons are leafy sea dragons and weedy sea dragons. The Birch Aquarium at the Scripps Institution of Oceanography houses both of them and hopes that their exhibit will lead to the leafy sea dragon being bred for the first time in captivity.

"It literally just looked like a piece of kelp," said Steven Kowal, visitor to the aquarium, according to Dayton News Daily. "It was crazy to me that it was, like, actually living and swimming around, so that's cool. I've never seen anything like that."

"They look like something out of this world," said Leslee Matsushige, the aquarium's associate curator. "When people see them move, you hear them say, 'What? That's alive? Wow! That's crazy.'"

The native population of sea dragons in Australia is threatened by pollution, warming oceans and illegal trade.