Sunday 19 May
Olive-brown sea snake (Aipysurus laevis)
- Although the olive-brown sea snake is an air-breather, it can remain underwater for long periods of time.
- The olive-brown sea snake has structures known as photoreceptors on its tail, which detect light.
What’s the World’s Favourite Species?Find out here.
Olive-brown sea snake fact file
- Find out more
- Print factsheet
Olive-brown sea snake description
The largest and bulkiest member of its genus (3), the olive-brown sea snake (Aipysurus laevis) has a stout, rounded body (4) and, unlike land snakes, a flattened, paddle-like tail suited to swimming (4) (5) (6). Its head is not distinct from the body, giving this species a worm-like appearance (5). The olive-brown sea snake’s scientific name, laevis, is derived from the latin word for ‘smooth’ (7), which presumably refers to its smooth skin (5).
One of six closely related species found in the beautiful reefs and shallow coastal waters of northern Australia (2), the olive-brown sea snake is highly variable in colour (3), ranging from plain brown to olive-brown, purplish-brown or grey on the upperparts, and becoming paler on the underside (2) (4) (8). The head is often olive-coloured (8), while the flattened tail is creamy white with a brown ridge along the upper surface (4).
The juvenile olive-brown sea snake is much less uniform in colour than the adult, showing a strongly banded pattern throughout its first year of life (8). This pattern is gradually lost as the juvenile matures (2).
The nostrils of the olive-brown sea snake are located on the top side of the snout (6), are semicircular in form (8), and have valves that allow them to be closed when underwater to prevent water from entering (9). This species has the longest fangs of any sea snake, growing to a length of about 4.2 millimetres (3).
- Also known as
- olive sea snake.
- Aipysure Lisse. Top
Carpenter, K.E. and Niem, V.H. (2001) The Living Marine Resources of the Western Central Pacific. Volume 6: Bony Fishes Part 4 (Labridae to Latimeriidae), Estuarine Crocodiles, Sea Turtles, Sea Snakes and Marine Mammals. Food and Agriculture Organization of the United Nations, Rome. Available at:
IUCN - Sea snakes:
Australian Marine Conservation Society:
University of Western Australia Oceans Institute:
- In the fishing industry, the part of the catch made up of non-target species.
- Diverse group of animals with jointed limbs and a hard external skeleton, characterised by the possession of two pairs of antennae, one pair of mandibles (mouthparts used for handling and processing food) and two pairs of maxillae (appendages used in eating, which are located behind the mandibles). Includes crabs, lobsters, shrimps, woodlice and barnacles.
- The fusion of gametes (male and female reproductive cells) to produce an embryo, which grows into a new individual.
- A category used in taxonomy, which is below ‘family’ and above ‘species’. A genus tends to contain species that have characteristics in common. The genus forms the first part of a ‘binomial’ Latin species name; the second part is the specific name.
- The state of being pregnant; the period from conception to birth.
- A diverse group of invertebrates, mainly marine, that have one or all of the following: a horny, toothed ribbon in the mouth (the radula), a shell covering the upper surface of the body, and a mantle or mantle cavity with a type of gill. Includes snails, slugs, shellfish, octopuses and squid.
IUCN Red List (August, 2012)
- Cousteau, F. (2008) Ocean: The World's Last Wilderness Revealed. Dorling Kindersley Ltd., London.
- Gopalakrishnakone, P. (1994) Sea Snake Toxinology. National University of Singapore Press, Singapore.
- Walker, P. and Wood, E. (2005) The Coral Reef. Infobase Publishing, New York.
- Marshall Cavendish (2000) Aquatic Life of the World, Volume 9. Marshall Cavendish, Singapore.
- Morrissey, J. and Sumich, J. (2011) Introduction to the Biology of Marine Life. Jones and Bartlett Publishers, Massachusetts.
The Reptile Database (August, 2012)
- Hutchings, P., Kingsford, M. and Hoegh-Guldberg, O. (Eds.) (2008) The Great Barrier Reef: Biology, Environment and Management. CSIRO Publishing, Victoria, Australia.
- O’Shea, M. (2008) Venomous Snakes of the World. New Holland Publishers, London.
- Heatwole, H. (1999) Sea Snakes. University of New South Wales Press, Sydney, Australia.
- Greene, H.W. (2000) Snakes: The Evolution of Mystery in Nature. University of California Press, Berkeley, California.
- view the contents of, and Material on, the website;
- download and retain copies of the Material on their personal systems in digital form in low resolution for their own personal use;
- teachers, lecturers and students may incorporate the Material in their educational material (including, but not limited to, their lesson plans, presentations, worksheets and projects) in hard copy and digital format for use within a registered educational establishment, provided that the integrity of the Material is maintained and that copyright ownership and authorship is appropriately acknowledged by the End User.
Olive-brown sea snake biology
The olive-brown sea snake hunts for its food by weaving among large corals on the reef, searching for unsuspecting prey resting in crevices and recesses (1) (2) (4). This species usually remains within a small patch of coral, and does not roam across large areas of the reef. It rarely ventures out into the open water, except after dark (2).
The olive-brown sea snake feeds on a wide variety of prey, including fish, fish eggs, crustaceans and molluscs (1) (3) (4) (5), and it incapacitates its victims with its venom. Olive-brown sea snake venom affects the muscles and nerves of its prey (10), and contains enzymes that break down the prey from the inside, making it easier for the sea snake to digest once swallowed (4).
Male olive-brown sea snakes reach sexual maturity in their third year (1), whereas females do not mature until they are four or five years old (1) (10). The breeding season of this species generally runs from May to July (3). Courtship in the olive-brown sea snake takes place in the open water, often with several males vying for the same female (4), while mating takes place on the reef floor (4) (11). Fertilisation is internal (5), and following a gestation period of nine months (2) (10), the female olive-brown sea snake gives birth to up to five live young (2) (5). Female olive-brown sea snakes are only thought to breed every second year (10) (11).Top
Olive-brown sea snake range
The olive-brown sea snake is a common and widespread species (1), found in the eastern Indian Ocean and the western Pacific Ocean (1) (2). Its distribution encompasses the waters around eastern Indonesia and New Guinea, and extends throughout tropical Australian waters east to New Caledonia (3) (7).Top
Olive-brown sea snake habitat
The olive-brown sea snake is found around coral reefs (1) (2) (4), estuaries (2) and tropical coastal shallows (2) (5). Around coral reefs, this species occurs in a variety of habitat types, including the reef edge and sandy bottoms adjacent to deeper reefs (1).Top
Olive-brown sea snake status
The olive-brown sea snake is classified as Least Concern (LC) on the IUCN Red List (1).Top
Olive-brown sea snake threats
Climate change causes various alterations to coral reef habitats, including the death of corals following mass bleaching, which in turn leads to a reduced abundance of prey and a reduction in suitable habitat for the olive-brown sea snake (1).
The olive-brown sea snake is known to be accidentally captured in trawl fisheries throughout its range, and given that this species takes a long time to mature, many individuals are caught before they have bred. In addition, the low reproductive output of the olive-brown sea snake, with just two to six offspring produced per female every other year, means that the species cannot sustain high levels of incidental capture (1).Top
Olive-brown sea snake conservation
The olive-brown sea snake is the most commonly found sea snake on Australia’s coral reefs (1), and there are currently no known conservation measures in place specifically targeting this species. However, recommendations have been made to monitor bycatch of this species, and for fisheries to use exclusion devices to reduce the levels of incidental catch (1).
All sea snake species in Australia are protected under their classification by the Department of Environment and Water Resources as ‘Listed Marine Species’. In addition, sea snakes are protected under the Environment Protection and Biodiversity Conservation Act 1999, while the Australian Fisheries Management Act 1991 requires fisheries to avoid impacting on protected or threatened species, including sea snakes (1). A three-year study has been instigated to develop and implement a long-term bycatch monitoring programme for Australia’s Northern Prawn Fishery, which has the largest impact of any Commonwealth-managed fishery on protected sea snake populations (1).
Since 2003, industry workshops have been jointly run by Australia’s Commonwealth Scientific and Industrial Research Organization (CSIRO) and Australia’s Fisheries Management Authority (AFMA) to train prawn fishery crew members on how to identify, photograph and record information regarding sea snake capture during the main prawn seasons (1).Top
Find out more
Find out more about sea snakes:
Learn more about marine conservation in Australia:
This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
More »Related species
Play the Team WILD game
This species is featured in:
This species is found in Barrow Island. Visit our Barrow Island topic page to find out more.
MyARKive offers the scrapbook feature to signed-up members, allowing you to organize your favourite ARKive images and videos and share them with friends.
Terms and Conditions of Use of Materials
Copyright in this website and materials contained on this website (Material) belongs to Wildscreen or its licensors.
Visitors to this website (End Users) are entitled to:
End Users shall not copy or otherwise extract, alter or manipulate Material other than as permitted in these Terms and Conditions of Use of Materials.
Additional use of flagged material
Green flagged material
Certain Material on this website (Licence 4 Material) displays a green flag next to the Material and is available for not-for-profit conservation or educational use. This material may be used by End Users, who are individuals or organisations that are in our opinion not-for-profit, for their not-for-profit conservation or not-for-profit educational purposes. Low resolution, watermarked images may be copied from this website by such End Users for such purposes. If you require high resolution or non-watermarked versions of the Material, please contact Wildscreen with details of your proposed use.
Creative commons material
Certain Material on this website has been licensed to Wildscreen under a Creative Commons Licence. These images are clearly marked with the Creative Commons buttons and may be used by End Users only in the way allowed by the specific Creative Commons Licence under which they have been submitted. Please see http://creativecommons.org for details.
Any other use
Please contact the copyright owners directly (copyright and contact details are shown for each media item) to negotiate terms and conditions for any use of Material other than those expressly permitted above. Please note that many of the contributors to ARKive are commercial operators and may request a fee for such use.
Save as permitted above, no person or organisation is permitted to incorporate any copyright material from this website into any other work or publication in any format (this includes but is not limited to: websites, Apps, CDs, DVDs, intranets, extranets, signage, digital communications or on printed materials for external or other distribution). Use of the Material for promotional, administrative or for-profit purposes is not permitted.