Animal Species:Common Seadragon, Phyllopteryx taeniolatus (Lacépède, 1804)

The species is related to the seahorses. Unlike seahorses however, the seadragons do not have a pouch for rearing the young. Instead, male seadragons carry the eggs fixed to the underside of the tail.

The standard name of the species has been changed in Australia to 'Common Seadragon'.  Most people know the fish by the name Weedy Seadragon.

Standard Common Name

Common Seadragon

Alternative Name/s

Weedy Seadragon, Lucas' Sea-dragon, Weedy Sea Dragon

Identification

The Common Seadragon has a long pipe-like snout with a small terminal mouth. Large females become deep bodied. The common name refers to the leaf-like appendages on the body. The species is the only member of the genus occurring in New South Wales, and cannot be confused with any other local member of the family Syngnathidae. It appears to be a frequently encountered member of the coastal fish fauna, especially by divers.

Size range

The species averages 30 cm in length, but can grow to 45 cm.

Distribution

The species is endemic to Australian temperate marine waters. It occurs from the central New South Wales coast around the south coast of Australia to south-western Western Australia.

The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Click on the map for detailed information.  Source: Atlas of Living Australia.

Phyllopteryx taeniolatus

Distribution by collection data

Ozcam map of CommonSeadragon specimens in Australian Museums.

What does this mean?

Habitat

This superbly camouflaged fish usually occurs in kelp-covered rocky reefs at depths from about 3 m to 50 m. It is usually found in areas ranging from shallow estuaries to deep offshore reefs (Pogonoski et.al., 2002). Depths range from 1 m - 50 m (Pogonoski et.al., 2002).

Feeding and Diet

The leaf-shaped appendages and cryptic colouration of this species provide effective camouflage, allowing them to feed on small crustaceans such as mysids.

Other behaviours and adaptations

These fish are poor swimmers, which explains the frequent beach strandings recorded in the Australian Museum database.

Mating and reproduction

The breeding season is early summer, with usually one brood per season. Male seadragons carry the eggs fixed to the underside of the tail until they eventually hatch. Up to 250 young hatch from a single brood (Pogonoski et al., 2002). Some of the young mature in one year, but usuaually will not breed until their second year when fully mature (Pogonoski et al., 2002).

View more information on the Dragon Search page on Preliminary Bioregional Summary of Sighting Data, January 1998 - June 2000.

The video below shows the courtship 'dance'.

Conservation Status

The Common Seadragon is protected in New South Wales and Tasmanian waters. It is listed in the 1997 IUCN Red List but only in the DD (Data Deficient) category. As of 2002, there was no evidence for any declines in the Common  Seadragon (Pogonoski et al., 2002). However it has been recognised the species would be most threatened by overcollecting of Common Seadragons for the aquarium fish trade (Pogonoski et al., 2002).

The aquarium trade is probably not a threat to this species because its temperate water requirement, diet and size make it difficult for the average aquarist to keep. Australian seadragons are not currently employed in traditional ethnic medicine, although dried and powdered seadragon can sell for up to A$200 per gram (Smith and Pollard, 1996). Fisheries impacts are minimal. The rocky coastal habitat of this species is not under threat from trawling and, owing to their feeding mode, this species is not caught by line fishers.

Classification

Species:
taeniolatus
Genus:
Phyllopteryx
Family:
Syngnathidae
Order:
Gasterosteiformes
Class:
Actinopterygii
Subphylum:
Vertebrata
Phylum:
Chordata
Kingdom:
Animalia

What does this mean?

References

  1. Dawson, C.E., 1985. Indo-Pacific Pipefishes (Red Sea to the Americas). Ocean Springs (USA): Gulf Coast Research Laboratory. pp. 1-230. (pp. 158-160).
  2. Dawson, C.E. in Gomon, M.F, J.C.M. Glover & R.H. Kuiter (Eds). 1994. The Fishes of Australia's South Coast. State Print, Adelaide. Pp. 992.
  3. Hutchins, B. & R. Swainston. 1986. Sea Fishes of Southern Australia. Complete Field Guide for Anglers and Divers. Swainston Publishing. Pp. 180.
  4. Kuiter, R.H. 1993. Coastal Fishes of south-eastern Australia. Crawford House Press. Pp. 437.
  5. Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. New Holland. Pp. 433.
  6. Kuiter, R.H. 2000. Coastal Fishes of South-eastern Australia. Gary Allen. Pp. 437.
  7. Kuiter, R.H. 2000. Seahorses, Pipefishes and their Relatives. A Comprehensive Guide to Syngnathiformes. TMC Publishing Pp. 240.
  8. Paxton, J.R., D.F. Hoese, G.R. Allen & J.E. Hanley. 1989. Zoological Catalogue of Australia Vol.7 Pisces Petromyzontidae to Carangidae. Canberra: Australian Biological Resources Survey. pp. i-xii, 1-665.
  9. Pogonoski, J.J., Pollard, D.A. & J.R. Paxton. 2002. Conservation Overview and Action Plan for Australian Threatened and Potentially Threatened Marine and Estuarine Fishes. Canberra: Environment Australia. Pp. 199-201.
  10. Smith, A.K. & Pollard, D.A. 1996, The best available information - some case studies from NSW, Australia, of conservation-related management responses which impact on recreational fishers. Marine Policy, vol.20, no.3, p.261-67.


Mark McGrouther , Collection Manager, Ichthyology
Last Updated:

Tags fishes, ichthyology, Weedy Seadragon, Phyllopteryx taeniolatus, Syngnathidae, Common Seadragon, weed, sea, dragon, weedy, common,

6 comments

Sascha Schulz - 12.06 PM, 02 June 2010

Hi LK,

If you look at the large version of the headshot of a Weedy Seadragon (second from the top), you will see small white dots in the background of the photo. Those white dots are mysid shrimps, which the Weedy Seadragon was hunting.

Weedy Seadragons slowly float towards their prey, the act of capture being a small dart of the head forwards and the shrimps are sucked into the long mouth tube.

Mark McGrouther - 8.06 AM, 02 June 2010

Hi Lifeknife,  Actually, they don't eat kelp.  They eat mysids and small crustaceans.  Check out the information above under 'Feeding and Diet'.  Helfman, et. al. (2009) state that, "Temperate waters are relatively lacking in herbivores, although some marine families (porgies, sea chubs, Aplodactylidae, Odacidae, [Removed]lebacks) feed heavily on plant matter".

Reference:
Helfman, G.S, Collette, B.B., Facey, D.E. and B.W. Bowen. 2009. The diversity of fishes: biology, evolution and ecology. 2nd edn. Wiley-Blackwell, Chichester. Pp. 720.
 

 

Lifeknife29 - 8.06 PM, 01 June 2010
hey mark, thanx for the info but this is what i found so far. Weedy seadragons eat kelp right? would their be any other species that eat kelp? maybe they are dying of hunger.
Mark McGrouther - 8.05 AM, 31 May 2010

Hi Lifeknife.  The threatening processes for the species were listed in Pogonoski, Pollard and Paxton (2002) 'Conservation Overview and Action Plan for Australian Threatened and Potentially Threatened Marine and Estuarine Fishes (download 1479 kb). They stated that "Over-collecting for the marine aquarium fish trade has the potential to impact on the populations of this species'. The Weedy Seadragon's conservation status was listed as 'lower risk (conservation dependent).  I hope you find the report useful.

Lifeknife29 - 1.05 PM, 30 May 2010
Hey im reaserching the weedy seadragon but i can't find specific things that threatens them. Do you know anything that threatens them maybe sewage?

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