Hydrophis ornatus 

Scope: Global
Language: English

Translate page into:

Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Reptilia Squamata Elapidae

Scientific Name: Hydrophis ornatus (Gray, 1842)
Common Name(s):
English Ornate Reef Sea Snake, Ornate Sea Snake
French Hydrophidae Orne
Aturia ornata Gray, 1842
Chitulia ornata (Gray, 1842)
Disteira ornata (Gray, 1842)
Taxonomic Notes: This species has three subspecies: Hydrophis ornatus ornatus (Gray, 1942), Hydrophis ornatus godeffroyi Peters, 1873, and Hydrophis ornatus ocellatus Gray, 1849. The status of these subspecies is very uncertain, and the subspecies ocellatus is treated in this assessment as a separate distinct species (H. Cogger pers. comm. 2009).

H. lamberti has been considered a synonym of H. ornatus (Smith 1926).

This species has also been treated under the genus Chitulia.

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2010
Date Assessed: 2009-02-15
Assessor(s): Rasmussen, A., Lukoschek, V., & Lobo, A.
Reviewer(s): Livingstone, S.R., Elfes, C.T., Polidoro, B.A. & Carpenter, K.E. (Global Marine Species Assessment Coordinating Team)
This species is very widespread. It is caught as bycatch by trawl fisheries, but this is not considered a major threat, therefore it is listed as Least Concern.

Geographic Range [top]

Range Description:This species is found in the Arabian Gulf, east to Indonesia, China, and Taiwan (Heatwole 1999). It has also be found in New Caledonia and the Loyalty Islands (Ineich and Rasmussen 1997).
Countries occurrence:
Bahrain; Bangladesh; Cambodia; China; Hong Kong; India (Andaman Is., Nicobar Is.); Indonesia; Iran, Islamic Republic of; Iraq; Japan; Kuwait; Malaysia; Myanmar; New Caledonia; Oman; Pakistan; Palau; Papua New Guinea; Philippines; Qatar; Saudi Arabia; Singapore; Sri Lanka; Taiwan, Province of China; Thailand; United Arab Emirates; Viet Nam
FAO Marine Fishing Areas:
Indian Ocean – western; Indian Ocean – eastern; Pacific – northwest; Pacific – western central
Additional data:
Lower depth limit (metres):22
Range Map:Click here to open the map viewer and explore range.

Population [top]

Population:This species was sometimes caught as bycatch by trawlers in western Malaysia in 1989 (Stuebing and Voris 1989). It is fairly common in the Java Sea (Tomascik 1997).
Current Population Trend:Unknown
Additional data:
Population severely fragmented:No

Habitat and Ecology [top]

Habitat and Ecology:This species is found in coral reefs, turbid inshore waters, and estuaries (Heatwole 1999). It eats fish.

The general reproductive strategy for the species includes small clutches (commonly 2-5 individuals) of relatively large offspring (commonly 19-34 cm). There is evidence of synchronized annual reproduction (Rasmussen 1989).

Threats [top]

Major Threat(s): This species is caught as bycatch by trawlers in Sabah (Stuebing and Voris 1989).

Conservation Actions [top]

Conservation Actions: There are no species specific conservation measures for this species, but it may occur in marine protected areas.

No sea snake species is currently listed by CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora).

Classifications [top]

9. Marine Neritic -> 9.4. Marine Neritic - Subtidal Sandy
9. Marine Neritic -> 9.5. Marine Neritic - Subtidal Sandy-Mud
9. Marine Neritic -> 9.10. Marine Neritic - Estuaries

In-Place Research, Monitoring and Planning
In-Place Land/Water Protection and Management
  Occur in at least one PA:Unknown
In-Place Species Management
In-Place Education
5. Biological resource use -> 5.4. Fishing & harvesting aquatic resources -> 5.4.4. Unintentional effects: (large scale) [harvest]
♦ timing:Ongoing    
→ Stresses
  • 2. Species Stresses -> 2.1. Species mortality

Bibliography [top]

Greer, A.E. 2006. Encyclopedia of Australian Reptiles. Available at:

Guinea, M.L. 2007. Marine Snakes: Species Profile for the North-western Planning Area. Report for the Department of the Environment, Water, Heritage and the Arts. Charles Darwin University, Darwin, NT.

Heatwole, H. 1999. Sea Snakes. Krieger Publishing Company, Malabar, Florida.

Ineich, I. and Rasmussen, A.R. 1997. Sea snakes from New Caledonia and the Loyalty Islands (Elapidae, Laticaudinae and Hydrophiinae). Zoosystema 19(2-3): 185-191.

IUCN. 2010. IUCN Red List of Threatened Species (ver. 2010.4). Available at: (Accessed: 27 October 2010).

Rasmussen, A.R. 1989. An analysis of Hydrophis ornatus (Gray), H. lamberti Smith, and H. inornatus (Gray) (Hydrophiidae, Serpentes) based on samples from carious localities, with remarks on feeding and breeding biology of H. ornatus. Amphibia-Reptilia 10(1989): 397-417.

Redfield, J.A., Holmes, J.C. and Holmes, R.D. 1978. Sea snakes of the eastern Gulf of Carpentatria. Australian Journal of Marine and Freshwater Research 29(3): 325-334.

Smith, M.A. 1926. Monograph of the Sea Snakes (Hydrophiidae). British Museum, London.

Stuebing, R. and Voris, H.K. 1990. Relative abundance of marine snakes on the west coast of Sabah, Malaysia. Journal of Herpetology 24(2): 201-202.

Tomascik, T. 1997. The Ecology of the Indonesian Seas. Tuttle Publishing.

Citation: Rasmussen, A., Lukoschek, V., & Lobo, A. 2010. Hydrophis ornatus. The IUCN Red List of Threatened Species 2010: e.T176737A7293481. . Downloaded on 24 June 2018.
Disclaimer: To make use of this information, please check the <Terms of Use>.
Feedback: If you see any errors or have any questions or suggestions on what is shown on this page, please provide us with feedback so that we can correct or extend the information provided