November Species Spotlight

November species in the spotlight: Blue-ringed Octopus


At first glance, the blue-ringed octopus looks completely harmless and adorable but don’t let this facade fool you! Someone once told me “If nature didn’t bother to hide it, it's probably best you don’t touch it”. Despite its tiny cute appearance this octopus packs enough venom to kill over 20 humans within minutes.

Native to the Pacific Ocean, the blue-ringed octopus can be found in tide pools and coral reefs. They are extremely small (2.5 inches long) and usually yellow/sand colored, but bright blue rings appear when they are about to strike as a warning signal to potential predators.


It is extremely rare for blue-ringed octopi to bite humans as they usually stay hidden during the day and are awake at night. But will bite if they feel threatened, usually when cornered or handled. If bitten seek help immediately as it can kill in a very short period of time. Blue-ringed octopi have venom called tetrodotoxin. This is one of the deadliest venoms found in the ocean and rightly so the blue-ringed octopus is considered as one of the deadliest marine species. The octopi’s salivary glands produce the venom, and the bacteria gets dispersed through their beak. It’s primarily used when hunting: the octopus captures crabs, shrimp and small fish by pecking through its prey’s exoskeleton with its beak and inserting the venom.


I know what you’re thinking! What if it was to bite me? Well, first, the venom would block nerve signals throughout the body, causing muscle numbness. Other nasty symptoms include nausea, blindness, loss of senses and loss of motor skills. Finally it would cause muscle paralysis—including the muscles needed for humans to breathe. There is currently no antidote, but victims can be saved if artificial respiration is started immediately. On that note, if you ever encounter a blue-ringed octopus enjoy the experience but be mindful of its potential danger, keep a safe distance from it and you should be fine.





{Written by Matteo Degregori}