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Sea Snakes


Olive sea snake / Aipysurus laevis / Family - Hydrophiidae
Olive sea snake / Aipysurus laevis / Family - Hydrophiidae

Sea snakes are reptiles. They are related to land snakes, lizards, turtles and crocodiles. They have adapted to life in water by developing a paddle tail and a body shaped like the keel of a boat and they give birth to live young in the sea.


Sea snakes breathe air and have valved nostrils so that when they dive down they do not get a nose full of water. They usually stay down for about 20 or 30 minutes before coming up for another breath of air.

Sea snakes of the Great Barrier Reef

About 15 types of sea snake occur in Great Barrier Reef waters. The olive sea snake (Aipysurus laevis) is most commonly encountered by divers. Like all sea snakes it has a flattened tail and is an excellent swimmer.

Sea snakes are venemous

Sea snakes have a poisonous 'bite' that paralyses their prey. They carry some of the most potent poisons known in the animal kingdom but they have small fangs and are not normally aggressive animals. Sea snakes may feed on fish eggs or burrowing eels, but most feed on fish, even stonefish. Having few natural enemies, they are often inquisitive and will swim close to divers. Although there have been no reports of deaths from sea snake bites in the Great Barrier Reef region, all sea snakes should be treated with great respect.