Weedy seadragon

Weedy seadragon
Phyllopteryx taeniolatus in Cabbage Tree Bay, Sydney, Australia
Conservation status

Near Threatened  (IUCN 3.1)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Syngnathiformes
Family: Syngnathidae
Subfamily: Syngnathinae
Genus: Phyllopteryx
Species: P. taeniolatus
Binomial name
Phyllopteryx taeniolatus
(Lacepède, 1804)
Phyllopteryx taeniolatus range

Weedy seadragon or common seadragon (Phyllopteryx taeniolatus) is a marine fish related to the seahorse. Adult weedy seadragons are a reddish colour, with yellow and purple markings; they have small leaf-like appendages that resemble kelp fronds providing camouflage and a number of short spines for protection.[1][2] Males have narrower bodies and are darker than females.[2] Seadragons have a long dorsal fin along the back and small pectoral fins on either side of the neck, which provide balance.[3] Weedy seadragons can reach 45 cm in length.

The weedy seadragon is the marine emblem of the Australian State of Victoria.[4]

Weedy Seadragon, Phyllopteryx taeniolatus, from the Sketchbook of fishes by William Buelow Gould, 1832

Range

The weedy seadragon is endemic to Australian waters of the Eastern Indian Ocean and the South Western Pacific Ocean. It can be found approximately between Port Stephens, New South Wales and Geraldton, Western Australia, as well as Tasmania.[5]

Habitat

The weedy seadragon inhabits coastal waters down to at least 50 m deep. It is associated with rocky reefs, seaweed beds, seagrass meadows and structures colonised by seaweed.[6]

Biology

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.[2] They lack a prehensile tail that enables similar species to clasp and anchor themselves.

Individuals are observed either on their own or in pairs; feeding on tiny crustaceans and other zooplankton by sucking prey into their toothless mouths.[2] 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.[2] The eggs are fertilised and carried by the male for around a month before the hatchlings emerge.[2] Seadragons, seahorses and pipefish are among the few known species where the male carries the eggs. The young are independent at birth, beginning to eat shortly after.[7]

Phyllopteryx taeniolatus

Mating in captivity is rare since researchers have yet to understand what biological or environmental factors trigger them to reproduce. In captivity the survival rate for weedy seadragons is about 60%.[8]

The Aquarium of the Pacific in Long Beach, California and the Tennessee Aquarium in Chattanooga, Tennessee[9] in the USA, and the Melbourne Aquarium in Melbourne, Australia[10] are among the few facilities in the world to have successfully bred weedy seadragons in captivity, though others occasionally report egg laying.[11] In March 2012 the Georgia Aquarium in Atlanta, USA, announced a successful breeding event of weedy seadragons.[12] As of July 2012, the Monterey Bay Aquarium has also successfully bred and hatched out baby weedy seadragons on exhibit.[13]

Threats

The weedy sea dragon is classified as Near Threatened (NT) on the IUCN Red List 2006.[14] While the weedy sea dragon is a desired species in the international aquarium trade, the volume of wild-caught individuals is small and therefore not currently a major threat. Instead, habitat loss and degradation due to human activities and pollution threaten weedy sea dragons most. The loss of suitable seagrass beds, coupled with natural history traits that make them poor dispersers, put the future of sea dragon populations at risk. This species is not at present a victim of bycatch or a target of trade in Traditional Chinese Medicine, two activities which are currently a threat to many related seahorse and pipefish populations.[15][16]

Conservation

It is illegal to take or export these species in most of the states within which they occur.[2] 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]

Related species

The weedy seadragon is in the subfamily Syngnathinae, which contains all pipefish. It is most closely related to the other member of its genus, the ruby seadragon (Phyllopteryx dewysea), and also the leafy seadragon (Phycodurus eques). Haliichthys taeniophorus, sometimes referred to as the "ribboned seadragon" is not closely related (it does not form a true monophyletic clade with weedy and leafy seadragons).[17]

The weedy seadragon was previously the only member of its genus until the discovery of the Ruby seadragon in 2015. [18]

Ongoing research

In the November 2006 issue of National Geographic magazine, marine biologist Greg Rouse is reported as investigating the DNA variation of the two seadragon species across their ranges.

References

This article incorporates text from the ARKive fact-file "Weedy seadragon" under the Creative Commons Attribution-ShareAlike 3.0 Unported License and the GFDL.

  1. ↑ Bray, D.J. 2011, Common Seadragon, Phyllopteryx taeniolatus, in Fishes of Australia, accessed 26 Aug 2014, http://www.fishesofaustralia.net.au/home/species/3127
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 "Dragon Search". Dragon Search. Retrieved April 2003.
  3. ↑ "Melbourne Aquarium". Melbourne Aquarium. Retrieved April 2003.
  4. ↑ Dept of Sustainability and Environment Victoria > The marine faunal emblem for the State of Victoria Retrieved 8 August 2011
  5. ↑ Froese, Rainer and Pauly, Daniel, eds. (2014). "Phyllopteryx taeniolatus" in FishBase. November 2014 version.
  6. ↑ "Western Australia Department of Fisheries". Western Australia Department of Fisheries. Retrieved April 2003.
  7. ↑ Morrison, S. & Storrie, A. (1999). Wonders of Western Waters: The Marine Life of South-Western Australia. CALM. p. 68. ISBN 0-7309-6894-4.
  8. ↑ Associated Press (12 June 2008). "Endangered sea dragon at Ga. aquarium pregnant". Newsvine. Retrieved 2 March 2015.
  9. ↑ Papercut Interactive. "Tennessee Aquarium". tnaqua.org.
  10. ↑ Melbourne Aquarium > Conservation Retrieved 6 April 2012.
  11. ↑ "Weedy Seadragons spawn for Hong Kong aquarist". AquaDaily. 2008-07-18. Retrieved 2009-02-01.
  12. ↑ Largest Brood of Weedy Sea Dragons Born at Georgia Aquarium Georgia Aquarium press release, 29 March 2012. Accessed 15 August 2013.
  13. ↑ Weedy Sea Dragons Born At Monterey Bay Aquarium Retrieved 5 August 2012
  14. ↑ "IUCN Red List". IUCN Red List. Retrieved May 2006.
  15. ↑ Martin-Smith, K. & Vincent, A. (2006): Exploitation and trade of Australian seahorses, pipehorses, sea dragons and pipefishes (Family Syngnathidae). Oryx, 40: 141-151.
  16. ↑ "Weedy Seadragon". Zoo Aquarium Association. Retrieved 6 Sep 2012.
  17. ↑ Wilson, N.G. & Rouse, G.W. (2010): Convergent camouflage and the non-monophyly of 'seadragons' (Syngnathidae:Teleostei): suggestions for a revised taxonomy of syngnathids. Zoologica Scripta, 39: 551-558.
  18. ↑ "Rare Ruby Seadragon uncovered in Western Australia". Western Australian Museum. Retrieved 19 February 2015.

External links

Media related to Weedy sea dragon at Wikimedia Commons