The Leafy Sea Dragon is one of the strangest and most magnificent creatures on this planet. A few years ago I was able to see them live in a wandering exhibition. Looking at them I could hardly believe such a strange creature existed. Like its smaller cousin, the Weedy Sea Dragon, this animal is a relative of Seahorses. However it is larger and even more interesting.
How to describe such a strange animal? At first glance, it looks like a floating tangle of yellow seaweed. But if you look more closely you can discern its body, looking like the stretched and horizontal body of a Seahorse. And like a Seahorse it has a distinct head with a kind of trunk and eyes that it can move independently of one another.
The body is of a strange shape: after the neck it becomes a bit thicker only to become as thin as the neck again. Then comes the main body, about twice as thick as the neck. After another thinning and thickening there is the tail, which makes for about half the total lenght of the animal. Unlike as with Seahorses, the tail cannot coil up.
A great many very leaf-like appendages are attached everywhere, even on the trunk. They are what gives the Leafy Sea Dragon its name. Their purpose is to camouflage the animal in the forests of seaweed where it makes its home.
It moves very slowly by propelling itself with its "leaves" in motions that could just as well be seaweed swaying in the currents. It really looks almost like a plant, and unlike as with other animals there seems to be no specific body plan it adheres to - the leaves look different on each individual, though not as different as one might think. (The number of leaves stays mostly the same, but their size and shape varies greaty.)
These animals are native to the seas of southern Australia, from about the Sydney area to south western Australia and to southern Tasmania. They live in coral reefs, rocky ledges, jetties, and sea grass forests, at dephts beyond thirty meters.
Since they have no teeth, they nourish themselves exlusively from small shrimp-like creatures (zooplankton) which they suck up through their trunks.
Like Seahorses, the Sea Dragons have a very curious mode of reproduction in that the males carry the eggs around with them. But unlike Seahorses those creatures do not have a pouch in which the eggs are deposited but rather carry them around externally, below the tail. Their skin forms a cup on each egg to keep it from falling off.
After an incubation time of about eight weeks, up to 250 young hatch during about a week's time. Since the young are released over a period of a few days, they are widely distributed and thus have a better chance of survival than if they hatched all at the same time and place.
Threats and Protection
Unlike its less spectacular cousin, the Weedy Sea Dragon, this fish is an endangered species. Although it has no known predators, it has become the target of unscrupulous "collectors" who have greatly decimated the population. The demand for these magnificent creatures is particularly great because they usually do not survive in captivity for very long.
Because of this threat, the Australian Government has declared the Leafy Sea Dragon to be a totally protected species. Thus it may not be captured or killed.
Note: There is some duplicate information in the Weedy Sea Dragon node. This was unavoidable because the two species are quite similar.