Image: Tom Weilenmann
Just for the record, the term ‘octopodes’ should be used to describe several different groups or species of octopus. To describe a group of the same species of octopus, the correct term is the slightly unattractive ‘octopuses’. And as for the term octopi, well, it isn’t even considered a real word! So that’s that cleared up.
‘Just when you thought it was safe to get back into the water’ seems a somewhat trite opening. But whatever the preamble, there remains another reason to watch your step when traipsing through the shallows of north Australia and Southeast Asia, albeit one that is a good deal more aesthetically pleasing than the ugly stonefish: the blue-ringed octopus.
Image: Stephen Childs
Beautiful and delicate as the coral itself, the four known species of blue-ringed octopus are largely nocturnal, spending their days nestled like land mines in makeshift nests – usually sea shells, but since the advent of man, these flexible invertebrates have made fruitful use of bottles and also cans. Unlike many sea creatures its size (the largest grow to about 57cm), the blue-ringed octopus has been known to become quite aggressive when its seclusion is disturbed – say, by the foot of a clumsy human. It will retract its arms to make its sharp beak protrude in an attempt to discharge one of nature’s most deadly poisons – the deadly toxin tetradodoxin.