Overview

Brief Summary

Biology

Seadragons are seen either solitarily or in pairs, they are slow-moving and rely on their elegant camouflage to provide protection from predators (2). In common with seahorses, it is the male seadragon that carries the developing eggs. The breeding season runs from October to March (5), and males develop a 'brood patch' on the underside of the tail that consists of cups of blood-rich tissue, which each hold an egg (4). The female transfers around 120 eggs into these pits; the eggs are then fertilised and carried by the male for about a month (2). Hatchlings emerge over several days and are initially only around 20 mm in length. They are extremely vulnerable to predation but grow quickly, attaining adult size by the time they are 2 years old (2). Seadragons feed on small organisms such as plankton and mysids by sucking them into their tube-like snout (2).
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Description

Leafy seadragons are exquisitely camouflaged fish. Belonging to the same family as seahorses and pipefish (Syngnathidae), they resemble these with their elongated snout and bony-plated body (2). Leafy seadragons are yellowish-brown to green in colour, although they may vary depending on their age, diet or location (2). The pectoral fins are located on the neck, and a dorsal fin runs along the seadragon's back (3). As their common name suggests, there are a number of leaf-like appendages along the body, which help to make these fish resemble the seaweed of their habitat. The eyes are located above the elongated snout and there are a number of defensive spines along the sides of the body (2).
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Comprehensive Description

Biology

Usually occur over sand patches close to reefs with kelp, feeding on mysids and other crustaceans. Ovoviviparous (Ref. 205). The male carries the eggs in a brood pouch which is found under the tail (Ref. 205). One of the most spectacular examples of camouflage: neither prey nor predators recognize it as a fish.
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Distribution

Range Description

Leafy seadragons appear to be most abundant in SA and southern WA. Until recently, the range was considered to form a continuous stretch of coastline from near Perth on the southern west coast of WA to Wilson’s Promontory in Vic (Kuiter 2000b). Recent sightings of live animals by divers have extended the known range along the WA coastline as far north as the Abrolhos Islands, west of Geraldton (Baker 2002). Unconfirmed reports of sightings come from Bass Strait Islands (King Is., Kent Group) of NW TAS (K. Martin-Smith, pers. comm).

The extent of occurrence can be approximated as the length of coastline along which it occurs (~ 14,000 km) and the width of the strip of habitat suitable for it to occupy along this coastline (less than 1 km in most places, and for this calculation assumed to be 0.1 km wide). The extent of occurrence is therefore estimated to be 1,400 km². Seadragons have been sighted at numerous locations within the range but it is impossible to determine how fragmented occurrence is. Total area of occupancy is possibly less than 2,000 km² (given the approximate extent of occurrence calculated above), but at this time is unknown.

The depth range of Leafy Seadragons is not well documented. Most reported encounters are with divers, and therefore necessarily in waters less than about 20 m. Seadragons have, however, been recorded down to 30 m in SA, WA and VIC (Kuiter 2000b).
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Eastern Indian Ocean: endemic to southern Australia.
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Geographic Range

Phycodurus eques (leafy seadragon), or Phycodurus eques as it is also known, lives in temperate waters exclusively off the southern coast of Australia as does its nearest relative, Phyllopteryx taeniolatus (weedy seadragon) (Dragon Search 2000; Wheeler 1975).

Biogeographic Regions: australian (Native )

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Australia: western Victoria, South Australia and Western Australia.
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Range

Endemic to southern Australia, the leafy seadragon is known from Geraldton in Western Australia to the Bellarine Peninsula, Victoria (5).
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Physical Description

Morphology

Physical Description

P. eques can grow to be 50 cm but averages 30 cm in length (Dragon Search 2000; Groves 1998; Zahl 1978). Typical of Syngnathidae, P. eques exhibits a series of hard, exoskeletal rings around its entire body and a toothless tube-like snout (Groves 1998). Broad, flat appendages resembling seaweed branch from the plates surrounding the body (Groves 1998). Amidst these appendages on the sides of the body are several sharp spines that aid in defense against predators (Dragon Search 2000). The frond-like appendages and thin body vary on adults from green to yellow-brown to light brown; some have thin white lines radiating from the eye and extending over the body (Dragon Search 2000; Wheeler 1975). Color variation occurs and depends on age, location, diet, and environmental stressors (Dragon Search 2000).

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Size

Maximum size: 350 mm TL
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Max. size

35.0 cm TL (male/unsexed; (Ref. 9002))
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Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
Leafy Seadragons were until recently considered to occur predominantly near rocky reefs supporting stands of kelp or other macroalgae, where they have been observed feeding on mysids and other crustaceans (Kuiter 2000a). Recent telemetry using ultrasonic transmitters has shown, however, that this species is just as prevalent over shallow (5–15 m depth) Posidonia seagrass meadows and patches of sand amongst seagrass (Connolly et al. 2002b).

Leafy Seadragons tracked over periods of up to 10 days typically remained within well-defined home ranges of up to 5 ha (Connolly et al. 2002b). Patterns of movement are characterised by short bursts (at average velocities of 2–17 m/h) punctuating long periods (up to 68 h) without movement. No diel pattern of movement is apparent (Connolly et al. 2002b).

As with other syngnathids, male seadragons carry the fertilized eggs. For Leafy Seadragons, the male carries about 200 eggs on the exposed surface of the underside of its tail (there is no pouch).

This species can survive for at least two to three years in aquaria if supplied with its specific live food requirements (P. Quong, pers. comm. in Pogonoski et al. 2002). Longevity in situ is not known. Phycodurus eques attains a maximum length of about 35 cm (Kuiter 1993).Mating reportedly occurs during summer months (Kuiter 2000b). Genetic structure of populations has not been measured, nor has any aspect of reproduction been quantified (e.g., number of mates, number of broods per season).

Phycodurus eques is particularly well camouflaged, with a number of frond-like appendages that resemble kelp. The species also rocks back and forth with wave action, increasing its resemblance to coastal algae swept by coastal surge (Gomon et al. 1994).

Systems
  • Marine
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Environment

reef-associated; non-migratory; marine; depth range 4 - 30 m (Ref. 9002)
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Living at depths of 5 to 15 meters, P. eques resides in areas with clear water, lower light conditions, and prominent vegetation. Such areas include seagrass meadows, seaweed beds, and rocky reefs (Dragon Search 2000; Groves 1998).

Aquatic Biomes: reef ; coastal

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Depth range based on 2 specimens in 1 taxon.
Water temperature and chemistry ranges based on 1 sample.

Environmental ranges
  Depth range (m): 25 - 37
  Temperature range (°C): 18.371 - 18.371
  Nitrate (umol/L): 0.171 - 0.171
  Salinity (PPS): 36.070 - 36.070
  Oxygen (ml/l): 5.271 - 5.271
  Phosphate (umol/l): 0.152 - 0.152
  Silicate (umol/l): 1.304 - 1.304

Graphical representation

Depth range (m): 25 - 37
 
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Inhabit rocky reefs, seaweed beds, seagrass meadows and structures colonised by seaweed. Leafy seadragons are found in shallow coastal waters down to at least 30 metres deep (5).
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Trophic Strategy

Found in inshore waters (Ref. 75154). Usually occur over sand patches close to reefs with kelp, feeding on mysids and other crustaceans (Ref. 9002).
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Food Habits

Mimicking surrounding vegetation, P. eques is able to quietly approach its unsuspecting prey (Groves 1998). The fish uses suction to draw food into its mouth, which it opens by expanding a joint on the lower snout. The major staple to the diet of P. eques is mysid shrimp. Plankton and larval fishes, however, are also part of its diet (Dragon Search 2000).

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Diseases and Parasites

Epitheliocystis. Bacterial diseases
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Life History and Behavior

Life Cycle

About 250 eggs are incubated by males on the underside of the tail, where they are embedded in spongy tissue (Ref. 31838).
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Reproduction

Unlike most fish species, in P. eques the male incubates the eggs. The female develops between 200 and 300 eggs. Concurrently, the male forms many capillaries on the tail, which then proceeds to swell, wrinkle, and form about 120 eggcups (Dragon Search 2000). The eggs are then transferred from the female onto the male's tail and fertilized, although little is known exactly how this occurs successfully (Groves 1998). Four weeks is the average incubation period, and hatching occurs over several days to maximize survival rates (Dragon Search 2000; Zahl 1978). For the first few days, a yolk sac provides nutrients. Soon after birth, the newborns are able to swim and hunt successfully. P. eques is approximately 20 mm at birth and grows to 20 cm within one year (Groves 1998). Between one and two years, the fish reaches maturity and can live for seven years in captivity (Groves 1998; Dragon Search 2000). Much of the reproduction, such as yearly breeding frequency, is yet unknown (Groves 1998).

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Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
NT
Near Threatened

Red List Criteria

Version
3.1

Year Assessed
2006

Assessor/s
Connolly, R.

Reviewer/s
Morgan, S.K. & Martin-Smith, K. (Syngnathid Red List Authority)

Contributor/s

Justification
More information is available about leafy seadragons than when the species was last assessed, and this has resulted in a reassessment of Near Threatened (NT). There remains a paucity of information describing population fluctuations, population size and life history traits, therefore the assessment focuses on criterion B (geographic range).

Population sizes have probably been reduced marginally through incidental impacts of fishing and the species’ habitat certainly has been adversely affected by pollution. However, these reductions have not been measured and probably represent a small proportion of totals of fish abundances and habitat extent.

Some issues point towards criteria within the Endangered (EN) category, and these points are described below. None of the information provides compelling evidence for trends in occurrence or occupancy, however this is largely due to the absence of data, rather than information that points towards population stability.

The extent of occurrence is estimated to be 1,400 km², which is below the 5,000 km² threshold for EN B1 and well below the 20,000 km² threshold for Vulnerable (VU). Total area of occupancy is possibly less than the VU threshold of 2,000 km² (given the approximate extent of occurrence calculated above), but at this time is unknown. Criterion B2 therefore cannot be used.

EN B1b(iii) (continuing decline in area, extent and/or quality of habitat) is met. Seadragon habitat such as algal covered reefs and seagrass meadows are being adversely affected by human activities and loss in quality and quantity of habitat has been documented (Baker 2003). The loss of habitat is most severe near major urban centres (e.g., Perth, Adelaide, Melbourne), where discharge of storm water and treated sewage leads to eutrophication and increased sedimentation. Losses of seagrass have been particularly severe along the metropolitan coasts and are well documented (Short and Wyllie-Echeverria 1996). The threat to seadragons may be lessened to an extent by the occurrence of seadragons at sites distant from these population centres, provided that these areas are biologically connected through movement or dispersal.

Seadragons have been sighted at numerous locations within the range but it is impossible to determine how fragmented occurrence is. Therefore, sub-criterion B1a cannot be used at present.

In summary, the lack of trend data means that seadragons cannot be described as meeting any of the threatened categories at present, but it nearly meets Endangered under criterion B (currently only on sub-criterion (B1b(iii)) is met). Therefore it is assessed as NT.

Continued monitoring is required to establish population trends. Research is also needed to establish areas of occupancy.

History
  • 1996
    Data Deficient
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Populations of P. eques have been declining due to both habitat destruction and aquarium harvest. Many conservation efforts including diver education, research efforts, and habitat preservation are currently underway in Australia to protect this species from decline (Dragon Search 2000).

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: near threatened

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Status

Classified as Near Threatened (NT) on the IUCN Red List (1).
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Population

Population
No firm population estimates exist for Leafy Seadragons, but an approximate estimate can be made using certain assumptions. Just one estimate of density exists for this species, from a single location at one time. Connolly et al. (2002a) estimated the density of Leafy Seadragons around West Island, in Encounter Bay, SA, using a mark/re-sighting method and a capture/recapture algorithm. The density of larger juveniles and adults at this site was 57 fish per ha. Small juveniles (< 100 mm) were not included in the study. In making a population estimate, the following estimations and assumptions were made:

1. The site at which Connolly et al. (2002a) worked was chosen because relatively frequent sightings had been made there previously. An average density across the distribution would be lower, probably much lower, and a figure of 5 fish per ha was used (approximately 10% of estimate by Connolly et al. (2002a)).

2. The coastline along which Leafy Seadragons occur is an estimated 14,000 km long.

3. The species occurs most frequently in a thin strip of shallow water along the coastline, typically in stands of macroalgae or in seagrass meadows. This strip is estimated to be, on average, 100 m wide, giving a total of 140,000 ha of occupancy.

At 5 fish per ha, the estimated total number of Leafy Seadragons is ~700,000. Confidence limits cannot be stated but the estimate is clearly based on very loose assumptions. The purpose of making such an estimate is to give perspective to the number of fish that might be removed from the wild (see Threats, below).

Mapping of habitat at sites far from major population centres and research into variability in habitat use at different sites is required to make the estimate of total population size more rigorous.

Population Trend
Unknown
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Threats

Major Threats
Leafy Seadragons lack a caudal fin and are weak swimmers; in conjunction with a lack of a dispersive egg phase, this potentially makes them vulnerable to habitat loss and degradation as well as to incidental harvesting during commercial fishing (Connolly et al. 2002b). These are the two main threats.

Leafy Seadragons are associated with seagrass beds and reefs supporting macroalgae (Connolly et al. 2002b). These habitats have been adversely affected by human activities and loss in quality and quantity of habitat has been documented (Baker 2003). The loss of habitat is most severe near major urban centres (e.g., Perth, Adelaide, Melbourne), where discharge of storm water and treated sewage leads to eutrophication and increased sedimentation. Losses of seagrass have been particularly severe along the metropolitan coasts and are well documented (Short and Wyllie-Echeverria 1996).

Connolly et al. (2002b) report anecdotal evidence that Leafy Seadragons are killed as incidental bycatch in the trawling industry in SA. Fishers have indicated that on occasions they catch “large numbers” of Leafy Seadragons. This information remains at the level of anecdote however, and neither the rate nor distribution of incidental catch have been substantiated. Measurement of incidental catch in SA would be beneficial, in that bycatch rates, compared with in situ densities, could be used to establish the relative threat posed by fisheries.

The legal collection of wild specimens has little likelihood of causing long-term changes in population sizes. The small numbers taken under legally issued permits could result in the reduction or loss of groups of animals at particular sites, but this is unlikely to result in measurable effects on regional populations. If demand increases substantially, illegal collection could threaten local and perhaps regional populations, although this possibility should remain unlikely given the difficulties associated with illegal international export.

This species is a major attraction for the dive industry in southern Australia, and it has been made the official fish emblem in the state of South Australia. Recreational divers often harass or disturb individuals (Kuiter 2000a). Suitable protocols for divers should be encouraged to protect local populations, but the disturbance probably does not harm the long-term prospects for regional populations.
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Near Threatened (NT)
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Unlike seahorses, seadragons are not in demand from the Traditional Chinese Medicine market but they may nevertheless be captured for the aquarium trade. Loss of habitat is considered the greatest threat to seadragons. Coastal habitats are increasingly damaged from the effects of urban and agricultural run-off, industrial pollution and other human activities and impacts (5).
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Management

Conservation Actions

Conservation Actions
Legislation (Source: Pogonoski et al. 2002)
1. Totally protected species in South Australian Waters (since 1987).
2. Protected Aquatic Biota in Victoria.
3. Totally Protected Fish Status in Western Australian Waters (since 1991).
4. Subject to Export controls since January 1st 1998, in the Commonwealth Wildlife Protection (Regulation of Exports and Imports) Act 1982.
5. Listed as marine species under s248 of The Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).
6. No Australian Society for Fish Biology listing.

More information (Source: Martin-Smith et al. 2003)
Australian pipehorses have been protected in Australian Commonwealth (federal) waters (greater than three nautical miles from the coast) since the beginning of 1998. As most pipehorses are caught in Commonwealth waters they are protected under the Environment Protection and Biodiversity Conservation Act 1999 wherein they are ‘listed marine species’. It is an offence to take, trade, injure or kill listed marine species except under permits issued by the Minister of the Environment. Such permits for exports of syngnathids are issued subject to a management plan, which must be approved by the executive agency, Environment Australia (within the Department of Environment and Heritage). Legal protection is variable for pipehorses caught in Australian State waters (less than three nautical miles from the coast), ranging from full to no protection.

Protected areas
All states of Australia are currently implementing systematic series of Marine Protected Areas (MPAs). Different states are at different stages of this process. The most important development for Leafy Seadragons is that a new MPA is close to being declared (it was released as a draft plan earlier in 2005) in southern Gulf St Vincent in the state of SA. The proposed MPA will include areas (e.g., Encounter Bay and northeastern Kangaroo Island) in which a large proportion of public sightings of seadragons occur. The protection of these areas could substantially decrease the perceived vulnerability of the species to human activities, in particular to commercial fishing. At this stage, however, levels of protection and locations of zones of high protection within the proposed MPA have not been finalised. Furthermore, MPAs offer no immediate protection against eutrophication and sedimentation threats to habitat from land-based sources.
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Conservation

Little is known about the population distribution of leafy seadragons, or much of their behaviour. They are fully protected in Australian waters (4). A database of seadragon sightings, known as 'Dragon Search' has been established with support from the Marine and Coastal Community Network (MCCN), Threatened Species Network (TSN) and the Australian Marine Conservation Society (AMCS), which encourages divers to report sightings (2). Monitoring of populations may provide indications of local water quality and seadragons could also become an important 'flagship' species for the often-overlooked richness of the unique flora and fauna of Australia's south coast (2).
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Relevance to Humans and Ecosystems

Benefits

Importance

fisheries: of no interest; aquarium: commercial
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Economic Importance for Humans: Positive

P. eques has traditionally been of economic importance to the aquarium fish trade. Due to its ornamentation, it is a desirable aquarium fish although difficult to maintain (Zahl 1978). This species also intrigues divers as it is very difficult to spot, and it is one of the many exotic Australian fishes that draw tourists from all parts of the globe (Groves 1998).

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Wikipedia

Leafy seadragon

The leafy seadragon or Glauert's seadragon,[1] Phycodurus eques, is a marine fish in the family Syngnathidae, which also includes the seahorses. It is the only member of the genus Phycodurus.

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. The leafy seadragon propels itself by means of a pectoral fin on the ridge of its neck and a dorsal fin 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.

Popularly known as "leafies", it is the marine emblem of the state of South Australia and a focus for local marine conservation.[2][3]

Description[edit]

Much like the seahorse, 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 20–24 cm (8–10 in). They feed on plankton and small crustaceans.

Leafy seadragon

The lobes of skin that grow on the leafy seadragon provide camouflage, giving it the appearance of seaweed.[4] 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 creature feeds by sucking up small crustaceans, such as amphipods and mysid shrimp, plankton, and larval fish through its long, pipe-like snout.[2]

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.[5] The leafy seadragon is related to the pipefish and belongs to the family Syngnathidae, 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, which is multicoloured and grows weed-like fins, but is smaller than the leafy seadragon. Another unique feature are the small, circular gill openings covering tufted gills, very unlike the crescent-shaped gill openings and ridged gills of most fish species.[6] Current research at the Scripps Institution of Oceanography is investigating the evolutionary relationships of the Syngnathidae[7] and the DNA variation of the two seadragon species across their ranges.[8]

Reproduction[edit]

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 to 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 in the eggs hatching 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. Leafy seadragons take about 28 months to reach sexual maturity.[9]

Movement[edit]

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 150 m (490 ft) per hour.[10]

Threats[edit]

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 often washed ashore after storms, as unlike their relative the seahorse, seadragons cannot curl their tails and hold into seagrasses to stay safe.[11]

The species have become endangered through pollution and industrial runoff, as well as collection by fascinated divers who are entranced by their unique appearance. 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.[1][12][13]

Habitat[edit]

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.[1][14] 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 (164 ft) deep, around kelp-covered rocks and clumps of sea grass.[2] They are commonly sighted by scuba divers near Adelaide in South Australia, especially at Rapid Bay, Edithburgh, and Victor Harbor.[15][16]

In captivity[edit]

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.[1] 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.[17]

Australia[edit]

Australian aquaria featuring leafy seadragons include the Sydney Aquarium,[18] the Melbourne Aquarium, and the Aquarium of Western Australia.[19]

Canada[edit]

Ripley's Aquarium of Canada in Toronto displays both leafy and weedy seadragons.[20][21]

United States[edit]

A number of aquaria in the United States have leafy seadragon research programs or displays. Among these are the Adventure Aquarium in Camden, New Jersey,[22] Aquarium of the Pacific at Long Beach,[23] the Birch Aquarium at Scripps, San Diego,[24] the Minnesota Zoo,[25] the Monterey Bay Aquarium[26] in California, the Dallas World Aquarium, Texas,[27] the New England Aquarium, Boston,[28] the Point Defiance Zoo & Aquarium in Tacoma, Washington,[29] the Shedd Aquarium, Chicago,[30] the California Academy of Sciences,[31] the Tennessee Aquarium,[32] Sea World Orlando, Florida[citation needed] and the Georgia Aquarium, Atlanta,[33] and the Pittsburgh Zoo & PPG Aquarium.[citation needed]

Cultural references[edit]

The leafy seadragon is the official marine emblem of the state of South Australia.[34] 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.[35][36]

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 southern Fleurieu Peninsula, with the theme of celebrating the leafy seadragon. The inaugural festival in 2005 attracted over 7,000 participants including 4000 visitors.[37]

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.[38][39][40] Made through a collaboration of The People's Republic of Animation, Waterline Productions and the SA Film Corporation,[41] the film is an introductory guide to marine conservation and the marine bioregions of South Australia suitable for 8-12 year olds,[42] 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.[43][44]

This animal was the basis of Dragalge from Generation 6 of the Pokemon Series.[verification needed]

This animal also has two pages devoted to it in Michael Hearst's book, Unusual Creatures where all of the unusual things about it are listed.[45]

See also[edit]

References[edit]

  1. ^ a b c d "Phycodurus eques". IUCN Red List of Threatened Species. Retrieved 6 April 2012. 
  2. ^ a b c "The Leafy Sea Dragon" (PDF). Yankalilla Visitor Information Centre.  Retrieved 17 August 2011.
  3. ^ "Leafy and Weedy Sea Dragon". Animals.NationalGeographic.com. Retrieved 9 December 2011. 
  4. ^ Cott, Hugh (1940). Adaptive Coloration in Animals. Oxford University Press. pp. 341–342.
  5. ^ New England Aquarium. "Leafy Sea Dragon". New England Aquarium Animals and Exhibits. Retrieved 9 July 2013. 
  6. ^ (Lourie 1999).
  7. ^ Wilson, N. G.; Rouse, G. W. (2010). "Convergent camouflage and the non-monophyly of ‘seadragons’ (Syngnathidae: Teleostei): suggestions for a revised taxonomy of syngnathids" 39. Zoologica Scripta. pp. 551–558. doi:10.1111/j.1463-6409.2010.00449.x. Retrieved 9 December 2011. 
  8. ^ "Seadragon Phylogeography". Scripps: Marine Invertebrates Phylogenetics Lab. Retrieved 9 December 2011. 
  9. ^ "Life History of the Weedy Sea Dragon". Research. Sydney Institute of Marine Science. 9 September 2008. Retrieved 13 October 2008. 
  10. ^ Connolly, R. M.; Melville, A. J.; Preston, K. M. (2002). "Patterns of movement and habitat use by leafy seadragons tracked ultrasonically.". Journal of Fish Biology (Oxford: Blackwell) (61): 684–695. 
  11. ^ "Zoo and Aquarium Association Inc". zooaquarium.org.au. Retrieved 8 August 2008. 
  12. ^ "Protected Aquatic and Priority Species". Department of Environment and Primary Industries, Victoria, Australia. Retrieved 29 April 2013. 
  13. ^ "ENVIRONMENT PROTECTION AND BIODIVERSITY CONSERVATION ACT 1999 - SECT 248". Australasian Legal Information Institute. Retrieved 29 April 2013. 
  14. ^ Morrison, Sue; Storrie, Ann (1999). Wonders of Western Waters. Como, Western Australia: Department of Conservation and Land Management. p. 112. ISBN 0-7309-6894-4. 
  15. ^ "Leafy sea dragon". Underwater Photography Guide Website. 
  16. ^ Neville Coleman; Nigel Marsh. "Victor Harbour (sic)". Underwater Australia. Neville Coleman. Retrieved 13 February 2013. 
  17. ^ Branshaw-Carlson, Paula (1–4 November 2011). Seadragon husbandry in the new millennium: Lessons learned from the past will create a sustainable future (PDF). "The Husbandry, Management and Conservation of Syngnathids". sheddaquarium.org. Chicago: 5th International Zoo and Aquarium Symposium. Retrieved 6 April 2012. 
  18. ^ "Southern Oceans: Leafy Sea Dragon". Sydney Aquarium. Retrieved 6 April 2012. 
  19. ^ "Aquarium of Western Australia" (PDF). aqwa.com.au. Retrieved 8 August 2011. 
  20. ^ Ripley's Aquarium of Canada > The Gallery Accessed 29 March 2014.
  21. ^ Stapen, Candyce H. (17 October 2013). "Discover underwater wonders at Toronto's new aquarium". USA TODAY. 
  22. ^ "Adventure Aquarium". Trip Advisor. 
  23. ^ "Online Learning Center: Leafy Seadragon". Aquarium of the Pacific. Retrieved 6 April 2012. 
  24. ^ "There's something about seahorses". aquarium.ucsd.edu. Birch Aquarium. Retrieved 6 April 2012. 
  25. ^ "Sea Dragons: Leafy and Weedy". mnzoo.org. Minnesota Zoo. Retrieved 14 February 2014. 
  26. ^ "Leafy sea dragon". Monterey Bay Aquarium. Retrieved 6 September 2011. 
  27. ^ "Exhibits of Southern Australia". Dallas World Aquarium. Retrieved 6 April 2012. 
  28. ^ "Animals and Exhibits: Leafy Seadragon". New England Aquarium. Retrieved 6 April 2012. 
  29. ^ "Aquariums". Point Defiance Zoo & Aquarium. Retrieved 6 April 2012. 
  30. ^ "Shedd Aquarium Rides Herd On Seahorse Conservation" (PDF). Shedd Aquarium. Retrieved 6 April 2012. 
  31. ^ "Live from the California Academy of Sciences" (PDF). California Academy of Sciences. Summer 2008. Retrieved 8 January 2013. 
  32. ^ "Leafy Seadragon". Tennessee Aquarium. Retrieved 6 April 2012. 
  33. ^ "Leafy Seadragon at the Atlanta, GA Aquarium - Picture of Georgia Aquarium, Atlanta". Trip Advisor. 
  34. ^ "Leafy Seadragon". Government of South Australia: Insignia and Emblems. Retrieved 19 July 2011. 
  35. ^ "The Adelaide University Skindiving Club". The Adelaide University Skindiving Club. Retrieved 24 April 2013. 
  36. ^ "Marine Life Society of South Australia". mlssa.asn.au. Retrieved 8 August 2011. 
  37. ^ "Leafy Sea Dragon Festival". District Council of Yankalilla. Retrieved 13 February 2013. 
  38. ^ "Newsletter" (PDF) (3-06). Marine Discovery Centre. Retrieved 17 August 2011. 
  39. ^ "Press release 13/6/2006: State's Marine emblem stars in new film". Department of Premier and Cabinet. 13 June 2006. Retrieved 17 August 2011. 
  40. ^ "The amazing adventures of Gavin a leafy seadragon". National Library of Australia. Retrieved 17 August 2011. 
  41. ^ "The amazing adventures of Gavin, a Leafy Seadragon". SA Film Corporation. Retrieved 17 August 2011. 
  42. ^ "Reef Watch: Newsletter" (PDF) (9.2). reefwatch.asn.au. June 2006. Retrieved 17 August 2011. 
  43. ^ "Marine Discovery Centre > Newsletter 3-08" (PDF). MarineDiscoveryCentre.com.au. Retrieved 17 August 2011. 
  44. ^ "Press release 24/8/2008: Gavin goes to school". Department of Premier and Cabinet. 24 August 2008. Retrieved 17 August 2011. 
  45. ^ Hearst, Michael. Unusual Creatures. 
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