When three baby sea dragons arrived at the Florida Aquarium last April, workers there quickly noticed something was wrong. Although the small fish usually float effortlessly in the water, these youngsters were sinking to the bottom of their tank. If they didn’t get help soon, the sea dragons would be unable to gather food and would eventually starve.
A veterinarian at the aquarium soon discovered that the baby fish were born without swim bladders. Normally, these internal organs fill with carbon dioxide, a by-product created when fish remove oxygen from the surrounding water as they breathe. The gas-filled sacs make the sea dragons less dense than the surrounding water, producing a buoyant force that helps them float.
The veterinarian, Ari Fustukjian, decided to make miniature floaties to help the sea dragons survive. Using buoyant material from a wet suit, he created tiny rings to fit around the animals. The rings allow the fish to swim and feed. “They’ve adjusted pretty well!” he says.