Leafy Sea Dragon

Sea Dragons are arguably the most spectacular and mysterious of all ocean fish. Though close relatives of sea horses, sea dragons have larger bodies and leaf-like appendages which enable them to hide among floating seaweed or kelp beds. Sea dragons feed on larval fishes and amphipods, such as and small shrimp-like crustaceans called mysids ("sea lice"), sucking up their prey in their small mouths. Many of these amphipods feed on the red algae that thrives in the shade of the kelp forests where the sea dragons live. As with their smaller common seahorse (and pipefish) cousins, the male sea dragon carries and incubates the eggs until they hatch. During mating the female deposits up to 250 eggs onto the "brood patch" on the underside of the male's tail. After about eight weeks, the brood hatches, but in nature only about 5 per cent of sea dragons survive to maturity (two years). A fully grown Leafy Sea Dragon grows to about 18 inches (45 cm). Leafy Sea Dragons are very interesting to watch-- the leafy appendages are not used for movement. The body of a sea dragon scarcely appears to move at all. Steering and turning is through movement of tiny, translucent fins along the sides of the head (pectoral fins, visible above) and propulsion derives from the dorsal fins (along the spine). Their movement is as though an invisible hand were helping, causing them to glide and tumble in peculiar but graceful patterns in slow-motion. This movement appears to mimic the swaying movements of the seaweed and kelp. Only close observation reveals movement of an eye or tiny fins. Most sources of information about sea dragons say they are found in the ocean waters of southern Western Australia, South Australia and further east along the coastline of Victoria province, Australia.  Sea dragons are protected under Australian law, and their export is strictly regulated. A 1996 assessment by the Australian government's Department of Environmental Heritage indicates "It [the Leafy Sea Dragon] is now completely protected in South Australia because demand for aquarium specimens threatened the species with extinction." Currently the specific law which protects them is called the Environment Protection and Biodiversity Conservation Act 1999.  For a February 2002 updated overview of the leafy sea dragon, see this page from the Department of Environmental Heritage site. The top image, the four images below on the left and on the bottom row are digital still camera images. The wallpaper images represented below are from video captures. Below these, three of the digital movies are 320 x 240 versions from the video, 10 frames/second with titles and sound. The fourth is 352 x 240 in size, 3.5 megabytes, with music, showing three camera views of a Leafy Sea Dragon. The fifth clip is most recent, a full 11.7 megabytes, with 27 seconds of 352 x 240 MPEG-1 video of Leafy Sea Dragons and music. In this front view of a Leafy Sea Dragon the leafy appendages almost appear to be antlers. The dark and light spots help break up the creature's outline. The bony, hatchet-like projection from between its independently moving eyes is nearly invisible from this perspective, though the two eyes clearly have a view capable of seeing an approaching threat from nearly any direction. Also noticeable is the large diameter of the mouth at the end of the snout-- a hinge on the lower side of the mouth allows it to expand to a diameter at least as large as the rest of the tubular snout. In recent years these creatures have become popular in various public aquariums all over the world. All candidate specimens are raised in captivity, then exported after reaching about half their adult size. Leafy dragons (or "leafies" as they are known by divers) grow to full size in one to two years. One barrier to their acquisition by aquariums is the tremendous expense of feeding them-- they feed on tiny live mysid shrimp by the hundreds, and one public aquarium biologist told me the tiny mysids cost up to 85 cents (U.S.) each to purchase. This leafy sea dragon's  kelp-shaped appendages present a confusing appearance, even when viewed from the front. The extensions on its head look like the stems of a plant. The pectoral fins on either side of its head are barely visible, as they beat rapidly in a rippling motion to steer the dragon from side to side. As with seahorses, sea dragons are very slow swimmers, relying on their ability to blend in with their surroundings for survival. This view of a Leafy Sea Dragon shows a tiny translucent fin along the side of the head (pectoral fin). The fin is nearly invisible, adding to the illusion that the animal is floating or pushed along by an invisible force. Note the hatchet-shaped bony projection protruding from between the eyes. As with its seahorse relatives, the eyes move independently. Divers report that "leafies" are very difficult to see in the wild, even to a trained observer, as they drift among the greenish-brown seaweed. With all those "leafy" appendages hanging off, it's easy to imagine how this Leafy Sea Dragon would blend in so perfectly in a kelp bed.  Sometimes even experienced dive photographers may not notice the animal even at arm's length, until it moves. Leafy sea dragons are ready to mate at an age of one year; at two years they are full size. In captivity, leafies may live to ten years or more.  According to an article by Peter DeMarco of the Boston Globe (Boston, Massachusetts, USA) aquariums pay up to 1,500 U.S. dollars each, which literally makes sea dragons worth more than their weight in gold! Additionally, their voracious appetite for about 100 mysid shrimp per day can get expensive. Each commercially purchased live mysid can cost in the range of 65-85 cents (U.S.) each, according to aquarists at the (Long Beach, California) Aquarium of the Pacific. This expense has prompted a newly initiated mysid-culturing program at the aquarium. A jumbled mass of leafy appendages pointing in all directions presents a bewildering view of a Leafy Sea Dragon as it slowly drifts toward the camera. Though camera flash units are not allowed to be used at most sea dragon aquarium exhibits, a low-powered movie light provides enough light to bring out many of its natural colors, without disturbing the animals. This view shows the distinctly military-looking "olive drab" color scheme on this Leafy Sea Dragon's appendages, a perfect design for hiding among vegetation. Also evident are short and long fleshy spines positioned along the side and top of the trunk. The appendages of a leafy sea dragon are flexible in much the same way as the seaweed and kelp vegetation in which it hides. The fins that provide for movement are nearly invisible, and the trunk may be curled slightly forward and under. Its tail is much less flexible and useful compared to its seahorse relative's prehensile tail. This sea dragon is swimming downward-- something you won't see a seahorse do. Seahorses swim vertically, or leaning forward slightly. Leafy sea dragons are known to not only swim slowly at odd angles, but may drift in the tidal surge or current, appearing to tumble out of control as they passively blend with the seaweed, kelp and other reef vegetation. Most aquarium visitors are not likely to recognize sea dragons as fish when viewing them for the first time. The camouflage of the leafy sea dragon is so perfect, it appears to be a plant even when swimming in open water. A diver has an even harder time identifying a "leafy", since in its natural habitat it may be hiding in clumps of floating seaweed or among kelp beds in dim light. Often the first identifying clue is the movement of an eye. This one appears to have tiny specks of dark algae growing along its trunk and leafy appendages. In the wild, shallow-water leafy sea dragon specimens tend to be yellow or greenish in color, while deep-water (over 20 meters or about 65 feet) dragons tend toward brown or red. In the temperate southern and southwestern waters of their native Australia the yellow-green variety is more likely to be encountered, since divers understandably avoid the deeper off-shore reefs, frequented by Great White Sharks. Unlike weedy sea dragons, leafies have never bred in captivity. Efforts continue and will hopefully be successful, especially since the IUCN (the World Conservation Union) has placed these animals on their Red List of Threatened Species. As aquarists learn to duplicate the conditions of nature in a captive environment, these efforts are more likely to succeed. Techniques include regulating the water temperature and the cyles of light. To simulate temperate ocean seasonal changes the water is changed from a nominal 55 degrees F to 66 degrees in the spawning season. Careful duplication of the seasonal intensity and duration of light can also enhance the chances of breeding. This view emphasizes the serpentine flow of the leafy sea dragon trunk, with the tail curled to the left. The pectoral fins, used in a rapid but subtle rippling motion for sideways movement, are nearly invisible. From an overhead view the bony head protrusion is seen to have a V-shaped cross-section, with each eye having a protective spike, tapering into a structure that looks like a blade. Just above the eye are seen some small fluorescent green patches, similar to those I've seen on many leafy dragons, especially on the fleshy appendages. I believe these could be small growths of algae.