Even if a Sea snake has what is described as a ‘gentle disposition’ they are dangerous and should be treated with the utmost respect.
The Sea snake is virtually the same as a land snake and indeed is in the same family as a Cobra.
They are not however, in the same class as Cobras when it comes to aggression and biting.
A lot of Sea snakes tend to be quite unaggressive and bite only when provoked this is borne out by the fact that photographs of scuba divers catching them and picking them up are fairly common.
This is on the one hand not too clever from the risk perspective (they WILL bite when you anger or frighten them) and on the other hand goes against the tenet of not touching or bothering sea life while diving –
Recently on a dive in South Africa, a diver who happened to be what he called a ‘former instructor’ took his glove off and was ‘tickling’ fish that were massing while feeding. The oils in the skin of a human destroy the protective slime on fish leaving them open to bacteria.
Even if the harm is minimal, what happens when every diver starts to handle the animals?
Ok - climbing down off my soap-box and back to the subject –
Sea snakes are air breathers and surface to breath having the ability to stay underwater for between two and eight hours depending on the species.
There are 62 species of varying venomous extent as well as temperament. I mentioned above their non-aggressive tendencies – they aren’t all like this so the people who get too close and handle them, will at some point get a shock!
They feed on fish, fish roe, shrimps, crabs, eels, catfish and worms. Not all eat all of these prey, in fact some snakes are quite particular about their prey eating only the eggs of one or two species of fish.
If you watch them they are very active while hunting for food, swimming close to the reef, putting their heads into holes and crevices looking for prey.
In the same way as other snakes, the jaws of the sea-snakes are loosely attached so they can dislocate them to enable them to swallow large prey.
They are preyed on by birds, sharks and large fish.
Some species breed on land by laying their eggs, others bear live young at sea.
The females often attract more than one male at sea so can be seen interacting in a group.
Most species are completely unsuited for land activity as they do not have enlarged ventral scales on their bellies to grip the ground and pull themselves along. If these are stranded onshore, they quite quickly die.
They grow up to 2 meters long and have a flattened, paddle-like, tail.
Their nostrils have evolved to shut when underwater.
In the same way as land snakes do, they deliver their poison through hollow fangs. The sea snake often has short fangs which do not necessarily penetrate all the way through a wetsuit.
They have no gills and are not related to eels.
In the same way land snakes do, sea snakes use their tongue to ‘smell’ underwater.
Their lungs have developed to a longer length to enable them to stay underwater for longer and they are able to absorb oxygen through their skin meeting about 20% of their requirement like this.
All of this allows the snake to spend significantly long periods underwater without surfacing.
They have a gland in their mouth which enables them to remove salt from their mouth with their tongue.
Sea snakes are widely distributed throughout the Indian and Western Pacific oceans and The Arabian Gulf. One species is found all along the coast of Africa from Djibouti in East Africa to the Cape Town coast in the south as well as right across to the Peru coast extending to the Gulf of California.
Sea snakes are not found in the Atlantic, the theory is the cold currents off Namibia and South America prohibit their crossing into these waters.
They inhabit the warmer shallow seas of the tropics and sub tropics, liking the muddy estuaries as well as the clear waters near reefs.
They are known to be quite curious and approach divers, it has been seen that they on occasion wrap themselves around divers regulator houses and limbs. The advice is do not become alarmed, wait patiently (and bravely!!!!) until they move off.
What happens if you are bitten
Bites where envonomation occurs are usually quite painless and often aren’t noticed when they happen. The fangs may also be left in the flesh.
Swelling is not significant, early symptoms are headache, thick tongue, thirst, sweats, vomiting.
Paralysis of the throat muscles as well as diaphragm can result which may cause fatalities.
Muscle breakdown may cause urine to turn red, dark brown or even black and progress to acute renal failure and eventual cardiac arrest.
A fatal dose of venom is 1.5 mg, most snakes produce 10 – 15mg of venom which is ten times more lethal than that of a Rattlesnake or a Black Mamba.
Attempts should be made to identify the snake – safely, even a dead snake can bite, inflicting a poisonous bite for up to an hour after decapitation.
Pressure immobilization of the wounded limb or body part as quickly as possible, using a wide pressure bandage from the bite wound as high up the limb as possible. Binding is similar to that which would be used for a sprain.
Seek medical attention as quickly as possible, leave the removal of bandages to the doctor.
Do not apply cooling or ice.
Stabilise breathing (ABC’s), CPR may be necessary
To read about other sea creatures like the Sea snake, click here
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