A sea snake: like a nightmare generated by a sleep app | Helen Sullivan

Watching sea snakes swim through water is soothing - until you remember they are real

Sea snakes are, in animal form, the feeling the deep end of the pool gives you when you are a child, when suddenly you feel you are swimming at night, or when you are in bed but not totally sure the floor beneath hasn't turned into water and sharks. And because sea snakes aren't where they're meant to be - everything you know tells you snakes don't belong in the sea - the more you learn about them, the more you encounter all that you don't know: the words are weird, you understand their meaning but can't read their letters, they are words in a dream - or was it a nightmare?

Black-banded sea kraits, a type of sea snake, hunt with yellow goatfish; in New Caledonia, they are called stripy sweaters". Kraits are elapid", which means their fangs are always erect. Sea snake lungs are almost as long as their bodies; they can breathe through their skin. Their tongues are shorter than those of land snakes: only the forked part pokes out.

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