'Leafies' are slightly smaller than weedies, some growing to 43cm, however most reach an average of 30cm. Their leafy appendages are more numerous and branching than on weedies and look distinctly like fronds of brown seaweed. Adults are green to yellow-brown with thin, pale dark-edged bands. As with many species of seahorse, seadragons are able to change colour depending on age, diet, location or even their stress level. Unlike weedies, the leafy seadragons' eyes are located slightly above the snout. Leafies have several long sharp spines along the sides of the body. These spines are thought to be used as a defence against attacking fish. New research has shown that leafy seadragons have a highly sophisticated navigation system, venturing hundreds of metres from their base but returning precisely to the same spot (Connolly 1998). The leafy seadragon has a much smaller range than the weedy. Leafies have been recorded from Geraldton in Western Australia along the southern Australian coastline to Wilsons Promontory in Victoria.Seaweed swayers
Seadragons resemble swaying seaweed, which can make them difficult to find in their natural habitats. They are slow moving and therefore rely heavily on camouflage for their survival. Their bright colours are revealed in sun dappled waters or under bright camera lights. Both species of seadragon inhabit rocky reefs, seaweed beds, seagrass meadows and structures colonised by seaweed. In the wild they live individually or in pairs are more often seen in shallow coastal waters. They feed by sucking plankton, larval fishes and small shrimp-like crustaceans, called mysids, into their small mouths. This is done by quickly expanding a joint on the lower part of their snout, causing a suction force that draws the food in (Groves 1998).
Male mothers, wrinkly tails and egg cups
As spring approaches, male and female seadragons pair. The female develops around 300 orange eggs in her lower abdominal cavity. The lower half of the tail on the male begins to form fine blood vessels near the surface, swells and looks wrinkled. He then develops about 120 small pits or 'egg cups' on the tail and the eggs are transferred from the female and fertilised. Although this transfer has yet to be observed, we suspect it occurs in the dark, pre-dawn hours. Dragon Searchers in Tasmaina are using infra-red video equipment to try and observe the egg transfer and other breeding behaviour of weedy seadragons.The male's tail swells and looks wrinkly as the 'egg cups' develop before egg transfer. Photo by Andrew Melville.
The male carries the eggs for an incubation period of about 4 weeks. The young seadragons hatch over several days. This staggered hatching is to aid dispersal and avoid competition for food amongst the young. At birth, seadragons are around 20mm long and are often differently coloured to the adults. The young are preyed upon by fish, crustaceans and sea anemones and live in different places to the adult seadragons. The young dragons are fast growing, reaching 20cm after one year and a mature length after about two years. It is not known how long wild seadragons live. In captivity it is thought that they can live for about 5 to 7 years. Seadragons, along with all other fish, have ear bones (otoliths) that show growth rings. New growth rings are continuously produced throughout the seadragon's life. One of the reasons dead beach-washed wild seadragons are very important is that it may be possible to age the beach-washed seadragons from these growth rings, therefore giving us a better understanding of the age of seadragons in the wild. The general health of the seadragon throughout its life and its changing growth rates can also be determined from the otoliths.
'Take two seahorses and go to bed'
There is increasing concern about the future of seadragons and other syngnathids in Australian waters. Seahorses, seadragons, and in particular, pipefish, are threatened globally by habitat destruction. An estimated 20 million seahorses (but not seadragons) are taken each year for traditional Asian medicines. The international trade in seahorses and pipefish involves more than 20 countries and is growing.
Fortunately seadragons currently are not used for the medicine trade, however they may be targeted in the aquarium fish trade. Keeping live seadragons is extremely difficult and collectors often target males with eggs, hatching out and selling the young. Removing these brooding animals from the wild populations may impact on local populations of seadragons. To date, no successful, closed cycle, captive-breeding program has occurred (ie getting a generation of captive-raised seadragons to breed). Economically and environmentally, it makes sense to limit collection and export of this species until we know more about them. Seadragons have a specific level of protection under fisheries legislation federally and in most Australian states where they occur, such that it is illegal to take or export them without a permit.
Why survey for seadragons?
It is only recently that the threats to marine biodiversity have been recognised. These threats relate indirectly or directly to development of coastal areas and pollution or exploitation by humans. There are numerous examples of marine mammals and birds that have become extinct or are threatened but little is known about the vast majority of marine invertebrates and fish (Jones and Kaly 1995), or their status.
Many people think of fish in the ocean as an inexhaustible resource. Most of the research on fish in Australia is on commercial species and little is known of the lives of even the most common non-commercial species. Divers who know their local areas and favourite dive spots can often see changes but are often a quiet minority. By making divers familiar with recording observations, the seadragon monitoring program aims to encourage divers to be pioneering researchers, since virtually nothing is known about many marine creatures, in the wild or captivity.
Most people are familiar with the "charismatic marine mega-vertebrates", marine mammals such as whales, dolphins or sea-lions. In southern Australia marine protected areas for threatened species relate to sea-lions and more recently in South Australia proposals of habitat protection for Southern Right Whales. There are however a number of fish and invertebrate species and their habitats that may be threatened, but there is little information available to assess their status or define areas for habitat protection.
There are usually limited resources for fisheries managers to investigate the conservation and management of fish that are not directly targeted by 'traditional' recreational or commercial fishing. With this in mind the Marine and Coastal Community Network (SA), the Threatened Species Network (SA) and the Marine Life Society of South Australia undertook to develop a database of leafy and weedy seadragon sightings. Seadragons are potentially a "flagship species" for marine conservation in southern waters. They are popular species that can serve as a rallying point for major conservation initiatives (Noss, 1990).
Fish such as the seadragon highlight the high degree of uniqueness or endemism of species that exists in southern temperate waters. For example, as well as the many unique fish and invertebrates, there are twice as many species of seaweeds alone in southern waters than on the Great Barrier Reef and off Ningaloo Reef in Western Australia. Australians are not generally aware of the immense marine biodiversity they have off their southern coast and the spectacular and unique environments that exist there.
Water-watch, Frogwatch and Environmental Protection Authority programs use frogs as a "charismatic" and useful indicator of freshwater water quality monitoring. Seadragons are colourful marine fish that could be adopted in a similar "mascot" capacity for marine water quality awareness. It has been suggested that seadragons may be sensitive to changes in water quality. Long-term monitoring of seadragon populations could also be useful as indicators of changes in water quality, especially in relation to catchment events.
There is widespread interest in developing community processes for the monitoring of salt-water environments, including mangroves, estuaries and sea grass. The Marine and Coastal Community Network hopes to encourage a adoption of similar community initiatives. Awareness generated by the Dragon Search project has been beneficial in generating interest in other marine monitoring projects such as Reefwatch, a community reef monitoring program.
A basic principle of the project is the assumption that learning about the marine environment and sharing your knowledge and enthusiasm is the one of the best ways to help make a difference. Seadragons are animals which stir up emotion and have encouraged a lot of curiosity in divers, beachcombers, teachers and students. By reducing marine pollution and conserving the marine environment for species such as seadragons we can also ensure a healthy environment for all our marine life.
Increased awareness and involvement of local communities may help prevent poaching of seadragons and encourage protection of both the species and its habitat. Responses to the project have already reflected this, with people from around the country contacting the project coordinators to express concern over potential threats. The ultimate aim of the project is to provide information to identify sites suitable for Marine Protected Areas for the species and habitat and to create an atmosphere of responsibility and ownership in the community towards these areas.
You could be a pioneering scientist
Some of the life history of seadragons is known from observing captive and, to a lesser extent, wild animals. More information about the basic ecology, distribution and movement in the wild needs to be collected to enable sensible management of these species. You can be a pioneering scientist by participating in Dragon Search. Note: Dragon Search is no longer able to collect sightings of seadragons. However, you can still report sightings through the Feral or In Peril project.
How to get involved!
Many recreational divers already record sightings of seadragons in their dive logs, and many other people observe beach-washed marine flora and fauna. It is a simple and most helpful step to transfer relevant information on seadragons to the Dragon Search sighting sheets (note: Dragon Search is no longer able to collect seadragon sightings but you can submit your sighting to the Feral or In Peril project). It is also extremely beneficial to have regular checks of the same sites and hence obtain information on trends in seadragon abundance over time. Even if you don't see seadragons on your dive, that information can be useful, especially if you have seen them at the site before. Remember safety comes first. Organise your underwater surveys as you would any other dive.
Dragon Search Seadragon Sighting Form that was used to report seadragon sightings.
What are we doing
Dragon Search no longer has part time coordinators in each Australian State where seadragons are known to occur. However, the data submitted will be pooled and can be periodically assessed to expand the existing reports. In South Australia, the Reef Watch Feral or In Peril program continues to provide education about seadragons.
What are the principal aims of Dragon Search?
1. To increase awareness, understanding and appreciation of syngnathid fish and the need for their protection and conservation.
2. To actively promote habitat protection and species conservation through the abatement of threats affecting the marine environment and syngnathid fish.
3. To establish a pilot program of community-based monitoring and a database that can be used as an aid to increase knowledge and define key habitat areas for syngnathids.
4. To instil community pride and custodianships for our unique marine environment and wildlife.
That face looks familiar
A research team from Griffith University has been using photographs to identify the facial patterns of individual Leafy Seadragons and sonic tagging techniques to learn more about their ecology and territorial behaviour. If you would like to contribute, the photographs need to be high quality, and show well-lit, close-ups of the face. You may like to photograph or video seadragons at the sites you dive regularly, to try and identify individuals. Observations of activity at night are also valuable.Individual leafy seadragons can be identified by their distinctive facial markings.
Information from the sighting sheets is automatically stored in a database. Our database containing the raw data is confidential and NO site specific information is passed on. Analysis of the Dragon Search databases from each State will be released as they are produced. These reports will based on Australia's marine bioregions. Dragon Search has actively encouraged syngnathid protection legislation nationally and at a state level. With the on-going success of this community-based survey program we hope to encourage the development of databases for other endemic and protected fish and invertebrate species.
Dragon Search promotes the need for marine reserves, not just for seadragons, but to conserve a comprehensive and representative range of our unique marine life and habitats. No-take marine reserves provide refuges for fish and therefore provide benefits to the local marine environment and in the long term the fishing industry. Dragon Search also supports the principles of Ecologically Sustainable Development.
I don't dive or snorkel, but want to help...
Seadragons can be found on the beach because they have bony-plates which help preserve their bodies after death. Beachcombers' reports of beach-washed seadragons can give us valuable information from areas that may be unsuitable for diving, following storms or in the colder months when diving activities generally decrease. Historical records and fishermen's and field naturalists' observations are also useful. Report seadragon sightings here.
Connolly, R. (1998). Measuring the home range of leafy seadragons. The Dragon's Lair Vol. 3 No. 2 : p3.
Gomon, M.F., Glover, J.C.M. & Kuiter, R.H. (eds.) (1994). 'The Fishes of Australia's South Coast'. (State Print : Adelaide).
Groves, P. (1998). Leafy seadragons. Scientific American December 1998 : 54-59.
Jones, G.P. & Kaly, U.L. (1995). Conservation of rare, threatened and endemic marine species in Australia, State of the Marine Environment Report, Technical Annex:1, The Marine Environment, Ocean Rescue, DEST, pp 183-191.
Noss, R.F. (1990). Indicators for measuring biodiversity: hierarchical approach. Conservation Biology4 : 355-364.
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