It looks like a bunch of kelp. But visitors to the aquarium are in for a surprise.

Its eye moves.

Ridges of tiny fins start to flutter.

It’s alive—gliding through the water like something from a fairy tale.

It’s . . . a sea dragon.

Workers at a Southern California aquarium have built what is believed to be one of the world’s largest habitats for sea dragons. The exhibit opened this spring at the Birch Aquarium at the Scripps Institution of Oceanography at the University of California San Diego.

There are only two types of sea dragons: leafy and weedy. Leafy sea dragons have leaf-shaped appendages all over their bodies. Weedy sea dragons are bony fish that look like a bit of seaweed. Both kinds are found only in a small area off Australia. Those native populations are threatened by pollution and because people capture and sell the creatures illegally as pets.

Only weedy sea dragons have been successfully bred in captivity before, and only rarely. With this large new habitat, aquarium workers hope to breed the leafy variety for the first time.

The Birch Aquarium’s 18-foot-long tank has three leafy sea dragons. Two are male. One is female. The aquarium has 11 weedy sea dragons. The 5,300-gallon tank is a HUGE space—especially for a leafy sea dragon! Leafy sea dragons grow to only about 14 inches long. The tank has grassy plants, a sandy bottom, and rocks.

The people who built the new sea dragon home hope it can be used to help save the leafy sea dragon species. Will the creatures use the large space to breed? If they do, it will look like this: Sea dragons mirror each other in a courtship dance. Then the female deposits her eggs onto a patch on the underside of the male’s tail. Like seahorses, male sea dragons carry the eggs until they hatch.

Sea dragons swim by spinning their fins while their tails act as rudders. They have no natural predators. No one wants to try chewing these creatures! Their slender bodies are covered by bony plates.