Octopuses are fascinating creatures to watch, and human diners consider some species to be delicacies. Although many live for years because of their skill at hiding in dark, secret dens, these intriguing cephalopods are favorite prey animals for sharks, fish, eels, and cetaceans including killer whales. But as scientists are discovering, not all of the organisms that enjoy octopus for lunch are megafauna; some of the weirdest creatures in the sea view octopuses as a food source.
Living and Dead, Octopuses Support Other Creatures
During their lifetimes, octopuses host a complete menagerie of parasites inside their bodies. Many of the creatures that call the octopus home live inside the creatures’ kidneys. An entire group of specialized organisms called Dicyemida and Rhombozoa make up their own animal phylum, yet they are only found living inside cephalopods’ kidneys. So specialized are these little hangers-on that scientists are capable of using them to determine one octopus species from another.
Most octopuses have a short life expectancy compared with other creatures; some live for just six months or so. Others, such as the giant pacific octopus, are able to survive for five years when conditions are favorable. Not only does the octopus generously feed other creatures throughout the course of its lifetime, it serves as a valuable food source for a wide range of animals once its life reaches an end. Yes, lobsters, crabs, and all sorts of other creatures that feed on detritus find octopus to be an excellent source of protein, but so do some strange little sea snails.
In a recent expedition to Antarctica, scientists found a tiny sea snail that is not normally a resident of this part of the ocean feasting on a deceased octopus at a depth of about 1,400 meters. The Bathysciadiid Limpet had attached itself to an octopus beak and was slowly digesting it, proving that not just large sea creatures prove valuable to organisms living in the bathysphere – so do small, humble ones such as the octopus.
As it turn out, some octopuses prey on others, often injecting their prey with paralyzing venom before dismembering and consuming them. But sometimes the tables are turned – even the blue-ringed octopus, which is capable of killing a person, has its predators. Certain fish including large moray eels seem to be immune to these venomous little cephalopods, gulping them down with no noticeable ill effects.
Just like other sea creatures, many octopuses become prey for almost any creature that can capture them. In areas where sea otters are making a comeback, they enjoy foraging for mollusks including octopuses. Seals and sea lions enjoy them too, although the octopuses’ ability to wedge themselves into tight spaces often makes it tough for pinnipeds to capture them. But once predators know that an octopus lives in a certain area, hiding can become a little more difficult – octopuses living in intertidal zones tend to stick to the same range encompassing as little as a few hundred meters.