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Sea Snake Bite

Sea Snake Bite Facts

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  • Sea snakes are usually 3-5 feet long (some can grow to 9 feet) with flat tails and scales. There are at least 52 species known and all of them are venomous. They are found in tropical and warm waters of the Pacific and Indian Oceans. There are no sea snakes in the Atlantic Ocean or Caribbean Sea. Although they evolved from terrestrial ancestors the vast majority cannot move on land.
  • They can move both forward and backwards in the water with equal speed. They can dive as deep as 328 feet and stay underwater for two hours. It is an air breather and must come to the surface to survive. A sea snake has scales where as eels do not.
  • Sea snakes are usually not aggressive unless provoked or cornered. Although they are highly venomous, only some bites result in significant symptoms or envenomation.
  • The venom in injected by fangs. Most species fangs are not long enough to penetrate through a wetsuit. The venom is very potent and toxic.
  • Bites typically occur when fishermen are removing the snakes from fishing nets or if the snake is stepped on while wading in the water.
  • Sea snakes can migrate into rivers from coastal waters and estuary settings (up to 3 miles).

What are the symptoms of a sea snake bite?

  • A bite from a sea snake does not cause pain initially.
  • The site of the bite may show only a small pin prick where the bite occurred without pain. Sea snakes bites could show anywhere from 1 to up to 20 "fang" marks.
  • The site of the bite rarely shows a reaction. The person who was bitten by the sea snake won't usually see redness, bruising, or other signs at the location of the bite, even if venom was injected.
  • Attempts should be made to capture or kill the snake for identification by an expert.

As sea snake venoms are neurotoxins, the typical symptoms of sea snake bites begin within three hours and include:

  • Painful muscles
  • Paralysis (inability to move) legs
  • Joint aches (arthralgias)
  • Blurry vision
  • "Thick tongue" with difficulty swallowing or speaking
  • Excessive saliva production
  • Vomiting
  • Droopy eye lids (ptosis)

If no symptoms develop within eight hours then venom injection is very unlikely.

Medically Reviewed by a Doctor on 6/22/2016
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Read What Your Physician is Reading on Medscape

Snake Envenomation, Sea »

Sea snakes, venomous elapid snakes that inhabit marine environments, are the most abundant and widely dispersed group of poisonous reptiles in the world.

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