The leafy seadragon (''Phycodurus eques'') or Glauert's seadragon, is the only member of the genus ''Phycodurus'' and is a marine

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% ...

in the family

Syngnathidae The Syngnathidae is a family of fish which includes seahorses, pipefishes, and seadragons ('' Phycodurus'' and '' Phyllopteryx''). The name is derived from grc, σύν (), meaning "together", and (), meaning "jaw". The fused jaw is one of the ...

, which includes seadragons,

pipefish Pipefishes or pipe-fishes (Syngnathinae) are a subfamily of small fishes, which, together with the seahorses and seadragons ('' Phycodurus'' and '' Phyllopteryx''), form the family Syngnathidae. Description Pipefish look like straight-bodied se ...

, and

seahorse A seahorse (also written ''sea-horse'' and ''sea horse'') is any of 46 species of small marine fish in the genus ''Hippocampus''. "Hippocampus" comes from the Ancient Greek (), itself from () meaning "horse" and () meaning "sea monster" or " ...

It is found along the southern and western coasts of Australia. The name is derived from the appearance, with long leaf-like protrusions coming from all over the body. These protrusions are not used for propulsion; they serve only as

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

. The leafy seadragon propels itself by means of a

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

on the ridge of its neck and a

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

on its back closer to the tail end. These small fins are almost completely transparent and difficult to see as they undulate minutely to move the creature sedately through the water, completing the illusion of floating

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of ''Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ke ...

. Popularly known as "leafies", it is the marine emblem of the state of

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

and a focus for local marine conservation.

Taxonomy

The generic name ''Phycodurus'' is derived from the Greek words ''phûkos'' "seaweed" and ''derma'' "skin".

Description

Much like the

, the leafy seadragon's name is derived from its resemblance to another creature (in this case, the mythical dragon). While not large, they are slightly larger than most seahorses, growing to about . They feed on

plankton Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a cr ...

and small

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean gro ...

s. The lobes of skin that grow on the leafy seadragon provide

, 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 related to the

and belongs to the family

, along with the seahorse. It differs from the seahorse in appearance, form of locomotion, and its inability to coil or grasp things with its tail. A related species is the

weedy seadragon The common seadragon or weedy seadragon (''Phyllopteryx taeniolatus'') is a marine fish related to the seahorses. Adult common seadragons are a reddish colour, with yellow and purple markings; they have small leaf-like appendages that resemble ...

, which is multicoloured and grows weed-like fins, but is smaller than the leafy seadragon. Another unique feature is the small, circular gill openings covering tufted gills, very unlike the crescent-shaped gill openings and ridged gills of most fish species.

Habitat and distribution

The leafy seadragon is found only in southern Australian waters, from

Wilson’s Promontory Wilsons Promontory, is a peninsula that forms the southernmost part of the Australian mainland, located in the state of Victoria. South Point at is the southernmost tip of Wilsons Promontory and hence of mainland Australia. Located at near ...

in Victoria at the eastern end of its range, westward to Jurien Bay, north of

Perth Perth is the list of Australian capital cities, capital and largest city of the Australian states and territories of Australia, state of Western Australia. It is the list of cities in Australia by population, fourth most populous city in Aust ...

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to ...

. 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 deep, around kelp-covered rocks and clumps of sea grass. They are commonly sighted by scuba divers near

Adelaide Adelaide ( ) is the list of Australian capital cities, capital city of South Australia, the state's largest city and the list of cities in Australia by population, fifth-most populous city in Australia. "Adelaide" may refer to either Greater A ...

in South Australia, especially at

Rapid Bay Rapid Bay is a locality that includes a small seaside town and bay on the west coast of the Fleurieu Peninsula, South Australia. It lies within the District Council of Yankalilla and its township is approximately 100 km south of the sta ...

, Edithburgh, and Victor Harbor.

Ecology

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, they are typically full grown and ready to breed. The species feeds by sucking up small crustaceans, such as

amphipods Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far descri ...

and

mysid shrimp Mysida is an order of small, shrimp-like crustaceans in the malacostracan superorder Peracarida. Their common name opossum shrimps stems from the presence of a brood pouch or "marsupium" in females. The fact that the larvae are reared in this ...

, and larval fish through its long, pipe-like snout.

Reproduction

As with seahorses, the male leafy seadragon cares for the

eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...

. The female produces up to 250 bright pink eggs, then deposits them onto the male's tail with her

ovipositor The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typica ...

, 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 Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

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. Despite this initial nutrition source, the majority of fry will instinctively learn to hunt and catch prey upon hatching, and will become self-reliant before the sac is gone.

Movement

The leafy seadragon uses the fins along the side of its head to allow it to steer and turn. However, its outer skin is fairly rigid, limiting mobility. Individual leafy seadragons have been observed remaining in one location for extended periods of time (up to 68 hours), but will sometimes move for lengthy periods. The tracking of one individual indicated it moved at up to per hour.

Conservation

Leafy seadragons are subject to many threats, both natural and man-made. They are caught by collectors, and used in

alternative medicine Alternative medicine is any practice that aims to achieve the healing effects of medicine despite lacking biological plausibility, testability, repeatability, or evidence from clinical trials. Complementary medicine (CM), complementary and ...

. 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 Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the ...

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

since 1991. Additionally, the species' listing in the

Australian government The Australian Government, also known as the Commonwealth Government, is the national government of Australia, a federal parliamentary constitutional monarchy. Like other Westminster-style systems of government, the Australian Government ...

's ''

Environment Protection and Biodiversity Conservation Act 1999 The ''Environment Protection and Biodiversity Conservation Act 1999'' (Cth) is an Act of the Parliament of Australia that provides a framework for protection of the Australian environment, including its biodiversity and its natural and cult ...

'' means that the welfare of the species has to be considered as a part of any developmental project.

In captivity

Due to being protected by law, obtaining seadragons is often an expensive and difficult process as they must be from captive bred stock, and exporters must prove their broodstock were caught before collecting restrictions went into effect, or that they had a license to collect seadragons. Seadragons have a specific level of protection under federal fisheries legislation as well as in most Australian states where they occur. Seadragons are difficult to maintain in aquaria. Success in keeping them has been largely confined to the public aquarium sector, due to funding and knowledge that would not be available to the average enthusiast. Attempts to breed the leafy seadragon in

captivity Captivity, or being held captive, is a state wherein humans or other animals are confined to a particular space and prevented from leaving or moving freely. An example in humans is imprisonment. Prisoners of war are usually held in captivity by a ...

have so far been unsuccessful.

Australia

Australian aquaria featuring leafy seadragons include the

Sydney Aquarium SEA LIFE Sydney Aquarium (formerly Sydney Aquarium) is a public aquarium that features a large variety of Australian aquatic life, displaying more than 700 species comprising more than 13,000 individual fish and other sea and water creatures fr ...

, the

Melbourne Aquarium Sea Life Melbourne Aquarium is a Southern Ocean and Antarctic aquarium in central Melbourne, Australia. It is located on the banks of the Yarra River beside and under the Flinders Street Viaduct and the King Street Bridge. The attraction is a ...

, and the Aquarium of Western Australia.

Canada

Ripley's Aquarium of Canada in

Toronto Toronto ( ; or ) is the capital city of the Provinces and territories of Canada, Canadian province of Ontario. With a recorded population of 2,794,356 in 2021, it is the List of the largest municipalities in Canada by population, most pop ...

displays both leafy and weedy seadragons.

South East Asia

S.E.A. Aquarium, located in the

Marine Life Park The Marine Life Park is a part of Resorts World Sentosa, Sentosa, situated in southern Singapore. The 8-hectare (20-acre) park houses two attractions, the S.E.A. Aquarium and the Adventure Cove Waterpark, and featured the largest oceanarium in ...

Singapore Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, borde ...

, displays both leafy and weedy seadragons.

United States

A number of aquaria in the United States have leafy seadragon research programs and/or displays. Among these are the Adventure Aquarium in Camden, New Jersey;

Aquarium of the Pacific The Aquarium of the Pacific (formerly the Long Beach Aquarium of the Pacific) is a public aquarium on a site on Rainbow Harbor in Long Beach, California, United States. It is situated across the water from the Long Beach Convention Center, Shor ...

at Long Beach; the Birch Aquarium at Scripps Institute in San Diego; the

Minnesota Zoo The Minnesota Zoo (formerly the Minnesota Zoological Garden), is an AZA-accredited zoo in Apple Valley, Minnesota. It is one of two state-supported zoos in the United States, with the other being the North Carolina Zoo. When it opened on May 2 ...

; the

Monterey Bay Aquarium Monterey Bay Aquarium is a Nonprofit organization, nonprofit public aquarium in Monterey, California, Monterey, California. Known for its regional focus on the marine habitats of Monterey Bay, it was the first to exhibit a living kelp forest w ...

; the Dallas World Aquarium & the Dallas Children's Aquarium, Dallas; the

New England Aquarium The New England Aquarium is a public aquarium located in Boston, Massachusetts. The species exhibited include harbor and northern fur seals, California sea lions, African and southern rockhopper penguins, giant Pacific octopuses, weedy seadr ...

, Boston; the

Point Defiance Zoo & Aquarium Point Defiance Zoo & Aquarium (PDZA) is the only combined zoo and aquarium in the Pacific Northwest, located in Tacoma, Washington, US, owned by Metro Parks Tacoma. Situated on in Tacoma's Point Defiance Park, the zoo and aquarium are home to ...

in Tacoma, Washington; the Shedd Aquarium, Chicago; the

California Academy of Sciences The California Academy of Sciences is a research institute and natural history museum in San Francisco, California, that is among the largest museums of natural history in the world, housing over 46 million specimens. The Academy began in 18 ...

; the Tennessee Aquarium; Sea World Orlando, Florida; the Pittsburgh Zoo & PPG Aquarium;, Ripley's Aquarium of the Smokies, Gatlinburg, Tennessee;, The Florida Aquarium in Tampa, Florida; the Mote Aquarium in Sarasota, Florida;, and Ripley's Aquarium Broadway at Myrtle Beach, South Carolina.

Cultural references

The leafy seadragon is the official marine emblem of the state of South Australia. It also features in the logos of the following South Australian associations — the

Adelaide University The University of Adelaide (informally Adelaide University) is a public research university located in Adelaide, South Australia. Established in 1874, it is the third-oldest university in Australia. The university's main campus is located on N ...

Scuba Club Inc. and the Marine Life Society of South Australia Inc. A biennial Leafy Sea Dragon Festival is held within the boundaries of the District Council of Yankalilla in South Australia. It is a festival of the environment, arts and culture of the

Fleurieu Peninsula The Fleurieu Peninsula () is a peninsula in the Australian state of South Australia located south of the state capital of Adelaide. History Before British colonisation of South Australia, the western side of the peninsula was occupied by the ...

, with the theme of celebrating the leafy seadragon. The inaugural festival in 2005 attracted over 7,000 participants including 4000 visitors. In 2006, an animated short film, ''The Amazing Adventures of Gavin, a Leafy Seadragon'', was made on behalf of several South Australian organisations involved in conserving the marine environment, including the Coast Protection Board, the Department of Environment and Heritage and the Marine Discovery Centre. Made through a collaboration of

The People's Republic of Animation The People's Republic of Animation (PRA) is an animation studio based in Adelaide, Australia. It began as a creator of music videos for Australian bands in 2003, and has since created award-winning short films and TV commercials, and developed f ...

, Waterline Productions and the SA Film Corporation, the film is an introductory guide to marine conservation and the marine

bioregion A bioregion is an ecologically and geographically defined area that is smaller than a biogeographic realm, but larger than an ecoregion or an ecosystem, in the World Wide Fund for Nature classification scheme. There is also an attempt to use th ...

s of South Australia suitable for 8-12 year olds, and copies were distributed on DVD to all primary schools in the State. An educator's resource kit to accompany the film was released in 2008. The semieducational animated series The Octonauts featured a father and two young leafy sea dragons in Season 2, Episode 18.

References

External links

Australia
Australian Museum > Leafy Seadragon
Retrieved 8 August 2011.
Marine Life Society of South Australia > Leafy Seadragon photos
Retrieved 8 August 2011.

Retrieved 8 August 2011.

Archived from the original webpage. Retrieved 17 February 2014.
Underwater Australasia > Vanishing Dragon
Article on making of a documentary film and DVD. Retrieved 8 August 2011.
Leafy sea dragon documentary film "The Vanishing Dragon" Scuba diving in South Australia
Retrieved 9 January 2013. International
Aquarium of the Pacific > Online Learning Center > Leafy Seadragon
Retrieved 8 August 2011.
Leafy seadragon information

Retrieved 17 August 2011.
Fused Jaw > Keep a Watchful Eye on the Sea Dragons of Southern Australia
Retrieved 8 August 2011.

Photo and multimedia gallery. Retrieved 8 August 2011.
MarineBio Conservation Society > ''Phycodurus eques'', Leafy Sea Dragons
Retrieved 8 August 2011. {{Authority control Syngnathidae Marine fish of Southern Australia Emblems of South Australia

leafy seadragon The leafy seadragon (''Phycodurus eques'') or Glauert's seadragon, is the only member of the genus ''Phycodurus'' and is a marine fish in the family Syngnathidae, which includes seadragons, pipefish, and seahorses. It is found along the sou ...

Taxa named by Albert Günther Articles containing video clips