A yellow bellied sea snake (Pelamis platurus) was found on a Dargaville beach recently.
New Zealands waters are usually too cold for theses tropical snakes, and its rare for one to be found alive. Bites to humans are fortunately uncommon, but symptoms include paralysis, kidney failure and heart toxicity - they can be fatal.
If someone is bitten immediately call an ambulance and then the National Poisons Centre. If you find a sea snake call the Police. Do not handle the snake even if it is dead as the bite reflex may persist.