Leafy Seadragon

Much like the seahorse, the leafy seadragon's name is derived from its resemblance to another creature (in this case, the mythical dragon). They are slightly larger than most seahorses, growing to about 20–24 cm (8–9.5 in). They feed on plankton and small crustaceans.

The lobes of skin that grow on the leafy seadragon provide camouflage, giving it the appearance of seaweed. It is able to maintain the illusion when swimming, appearing to move through the water like a piece of floating seaweed. It can also change colour to blend in, but this ability depends on the seadragon's diet, age, location, and stress level.

The leafy seadragon is found only in southern Australian waters, from Wilson's Promontory in Victoria at the eastern end of its range, westward to Jurien Bay, 220 km (140 mi) north of Perth in Western Australia. Individuals were once thought to have very restricted ranges; but further research has discovered that seadragons actually travel several hundred metres from their habitual locations, returning to the same spot using a strong sense of direction. They are mostly found over sand patches in waters up to 50 m (160 ft) deep, around kelp-covered rocks and clumps of seagrass. They are commonly sighted by scuba divers near Adelaide in South Australia, especially at Rapid Bay, Edithburgh, and Victor Harbor.

Leafy seadragons usually live a solitary lifestyle. When the time comes, males court the females, they then pair up to breed. From the moment they hatch, leafy seadragons are completely independent. By the age of two years, they are typically full grown and ready to breed.

The species feeds by sucking up small crustaceans, such as amphipods and mysid shrimp, plankton, and larval fish through its long, pipe-like snout.

As with seahorses, the male leafy seadragon cares for the eggs. The female produces up to 250 bright pink eggs, then deposits them onto the male's tail with her ovipositor, a long tube. The eggs then attach themselves to a brood patch, which supplies them with oxygen. After 9 weeks, the eggs begin to hatch, depending on water conditions. The eggs turn a ripe purple or orange over this period, after which the male pumps his tail until the young emerge, a process which takes place over 24–48 hours. The male aids the hatching of the eggs by shaking his tail, and rubbing it against seaweed and rocks. Once born, the young seadragon is completely independent, eating small zooplankton until large enough to hunt mysids. Only about 5% of the eggs survive. Each newborn fry begins life with a small, externally-attached yolk-sac. This sac provides them sustenance for their first few days of life.

Leafy seadragons are subject to many threats, both natural and man-made. They are caught by collectors, but unlike other syngnathid fish, are not used in alternative medicine. They are vulnerable when first born, and are slow swimmers, reducing their chance of escaping from a predator. Seadragons are sometimes washed ashore after storms.

The species has become endangered through pollution and industrial runoff, as well as collection for the aquarium trade. In response to these dangers, the species has been totally protected in South Australia since 1987, Victoria since at least 1995, and Western Australia since 1991. Additionally, the species' listing in the Australian government's Environment Protection and Biodiversity Conservation Act 1999 means that the welfare of the species has to be considered as a part of any developmental project.