Weedy seadragon (Phyllopteryx taeniolatus)
|Also known as:||Common seadragon|
|Size||Length: up to 46 cm (2)|
Classified as Near Threatened (NT) on the IUCN Red List 2006 (1).
Weedy seadragons are one of only two species of seadragons, the second is known as the leafy seadragon (Phycodurus eques) due to the greater number of leaf-like appendages along its body (2). Seadragons resemble the seahorses to which they are related, having a bony-plated body and elongated snout; their tails are not prehensile however (3). Adult weedy seadragons are a reddish colour, with yellow and purple markings; they have small leaf-like appendages that provide camouflage and a number of short spines for protection (4). Males have narrower bodies and are darker than females (4). Seadragons have a long dorsal fin along the back and small pectoral fins on either side of the neck, which provide balance (3).
Endemic to southern Australian waters, the weedy seadragon is found along the south coast from the Abrolhos Islands in Western Australia to Port Stephens, New South Wales. The range also includes the coast of Tasmania (3).
Inhabiting coastal waters down to at least 50 metres deep, weedy seadragons are associated with rocky reefs, seaweed beds, seagrass meadows and structures colonised by seaweed (6).
These fish are slow-moving and rely on their camouflage as protection against predation; they drift in the water and with the leaf-like appendages resemble the swaying seaweed of their habitat (4). Individuals are observed either on their own or in pairs; feeding on planktonic organisms by sucking prey into their toothless mouths (4). Like seahorses, seadragon males are the sex that cares for the developing eggs. Females lay around 120 eggs onto the brood patch located on the underside of the males tail (4). The eggs are fertilised and carried by the male for around a month before the hatchlings emerge (4).
This species is not at present a target of the trade in Traditional Chinese Medicine, which is currently affecting seahorse numbers. However, they are likely to be threatened by the destruction of habitat that is occurring along coastal waters as a result of development and pollution (5).
Currently, it is illegal to take or export these species in most of the states within which they occur (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 (4). 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 (4).
Authenticated (25/6/03) by Jeremy Gramp, Dragon Search.
- Dorsal fin: in fish, the unpaired fin found on the back of the body.
- Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
- Pectoral fin: in fish, the pair of fins that are found one on each side of the body just behind the gills. They are generally used for balancing and braking.
- Planktonic: aquatic organisms that drift with water movements; may be either phytoplankton (plants), or zooplankton (animals).
IUCN Red List (May, 2006)
Australia Museum online (April, 2003)
Melbourne Aquarium (April, 2003)
Dragon Search (April, 2003)
- Gramp, J. (2003) Pers. comm.
Western Australia Department of Fisheries (April, 2003)