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% of ...
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 t ...
, 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 " ...
s.
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
Undulation may refer to:
* Lateral undulation, the most primitive of vertebrate locomotor patterns
* Undulation of the geoid, the separation between the geoid and the reference ellipsoid of the Earth
* Undulation point, a point on a curve where t ...
minutely to move the creature sedately through the water, completing the illusion of floating
seaweed.
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
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 " ...
, 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 crucia ...
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 group can ...
s.
The lobes of skin that grow on the leafy seadragon provide
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 ...
, 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
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 belongs to 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 t ...
, 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 in
Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
at the eastern end of its range, westward to
Jurien Bay, north of
Perth
Perth is the capital and largest city of the Australian state of Western Australia. It is the fourth most populous city in Australia and Oceania, with a population of 2.1 million (80% of the state) living in Greater Perth in 2020. Perth i ...
in
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 th ...
.
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 capital city of South Australia, the state's largest city and the fifth-most populous city in Australia. "Adelaide" may refer to either Greater Adelaide (including the Adelaide Hills) or the Adelaide city centre. The dem ...
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 stat ...
,
Edithburgh
Edithburgh is a small town on the south-east corner of Yorke Peninsula situated on the coastline of Salt Creek Bay, in the state of South Australia. Edithburgh is about west of Adelaide across Gulf St Vincent, but away by road. At the 2016 ...
, 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 describ ...
and
mysid shrimp,
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 crucia ...
, 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, 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. 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
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
since at least 1995, and
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 th ...
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 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 f ...
, 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
The Aquarium of Western Australia (AQWA) is a privately owned aquarium in Hillarys, Western Australia. AQWA was Australia's largest aquarium when it opened and still possesses Australia's largest single aquarium and walk-through underwater tunn ...
.
Canada
Ripley's Aquarium of Canada
Ripley's Aquarium of Canada is a public aquarium in Toronto, Ontario, Canada. The aquarium is one of three aquariums owned-and-operated by Ripley Entertainment. It is located in downtown Toronto, just southeast of the CN Tower. The aquarium h ...
in
Toronto
Toronto ( ; or ) is the capital city of the Canadian province of Ontario. With a recorded population of 2,794,356 in 2021, it is the most populous city in Canada and the fourth most populous city in North America. The city is the anch ...
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 ...
of
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, bor ...
, 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
Birch Aquarium at Scripps (sometimes referred to as Scripps Aquarium or Birch Aquarium) is an aquarium and the public outreach center for Scripps Institution of Oceanography at the University of California, San Diego. Accredited by the Association ...
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 22, ...
; the
Monterey Bay Aquarium
Monterey Bay Aquarium is a nonprofit public aquarium in Monterey, California. Known for its regional focus on the marine habitats of Monterey Bay, it was the first to exhibit a living kelp forest when it opened in October 1984. Its biologists ...
; the
Dallas World Aquarium
The Dallas World Aquarium is a for-profit aquarium and zoo located in the West End Historic District of Dallas, Texas, USA. It aids conservation and education by housing many animals that are threatened or endangered as part of a cooperative b ...
& the
Dallas Children's Aquarium, Dallas; the
New England Aquarium, Boston; the
Point Defiance Zoo & Aquarium in Tacoma, Washington; the
Shedd Aquarium
Shedd Aquarium (formally the John G. Shedd Aquarium) is an indoor public aquarium in Chicago, Illinois, in the United States. Opened on May 30, 1930, the aquarium was for some time the largest indoor facility in the world. Today it holds about ...
, 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 1853 ...
; the
Tennessee Aquarium
The Tennessee Aquarium is a non-profit public aquarium located in Chattanooga, Tennessee, United States. It opened in 1992 on the banks of the Tennessee River in downtown Chattanooga, with a major expansion added in 2005. The aquarium, which has ...
;
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 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
The District Council of Yankalilla is a local government area centred on the town of Yankalilla on the Fleurieu Peninsula in South Australia.
It was created on 23 October 1856, when the District Council of Yankalilla and Myponga was divided i ...
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, 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 the ...
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
''Octonauts'' is a children's television series, produced by Silvergate Media for the BBC channel CBeebies, and based on the children's books written by Vicki Wong and Michael C. Murphy.
The show follows an underwater exploring crew made up o ...
featured a father and two young leafy sea dragons in Season 2, Episode 18.
See also
*
Sea Dragon (disambiguation)
*
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 ...
(Common seadragon)
*
Ruby seadragon
The ruby seadragon (''Phyllopteryx dewysea'') is a marine fish in the family Syngnathidae, which also includes seahorses. It inhabits the coast of Western Australia. The species was first described in 2015, making it only the third known specie ...
*
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 " ...
*
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 ...
References
Further reading
*
External links
Australia
Australian Museum > Leafy Seadragon Retrieved 8 August 2011.
Marine Life Society of South Australia > Leafy Seadragon photosRetrieved 8 August 2011.
Retrieved 8 August 2011.
Archived from the original webpage. Retrieved 17 February 2014.
Underwater Australasia > Vanishing DragonArticle 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 SeadragonRetrieved 8 August 2011.
Leafy seadragon informationRetrieved 17 August 2011.
Fused Jaw > Keep a Watchful Eye on the Sea Dragons of Southern AustraliaRetrieved 8 August 2011.
Photo and multimedia gallery. Retrieved 8 August 2011.
MarineBio Conservation Society > ''Phycodurus eques'', Leafy Sea DragonsRetrieved 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