If you’re in Australia, you may want to be aware of the Blue Ringed Octopus. It’s one of the deadliest sea creatures in the ocean. Because of its tetrodotoxin, it’s incredibly dangerous. When contact occurs, people rarely know they’ve been bit, and the symptoms come on rapidly. It only takes about 10 minutes for vomiting and total paralysis to manifest. Unless you have immediate medical attention, death is almost certain.