Those biting octopuses

In September, we noted that a bite from the South Pacific’s Blue Ring Octopus is deadly. That prompted reader Samuel Johnson to ask, “Do the octopuses that I encounter in the Caribbean bite, if given the opportunity? I’ve had friends report allowing octopuses to wander over and sit on and explore their bare hands. Is there any reason not to do this, either for my own health and safety or that of the octopus?”

Yes, indeed there is. All octopuses are equipped with a beak-like mouth and powerful jaw muscles. They seize prey with their arms, and use the beak to bite while injecting a venom to paralyze the victim. So, just about any octopus large enough to be noticed by a diver is also capable of biting. How severe that bite might be depends on the size of the octopus and where it bites you. A large octopus biting with full force on lightly or unprotected flesh could inflict some real damage.

Five species of octopus live in the Caribbean at depths frequented by divers; the largest approaches 7 feet in armspread. While there is no indication of anything comparable to the danger posed by the Indo-Pacific blue-ringed octopus (whose bite can be fatal within 20 minutes), one cannot rule out the possibility of a bad reaction in some individuals, given injection of sufficient quantities of these poisons in their blood.

As to the possible negative effects on the octopus’ health from being handled by divers, such encounters, no matter how benign the activity may appear, have the capacity to cause stress, alter behavior, disorient animals, and possibly cause infections. Wild marine animals deserve the same respect as do their wild terrestrial cousins. Look, but don’t touch.