A new paper published in the journal Ecology, the Ecological Society of America, has revealed that scrappy octopuses will punch fishes when hunting alongside them to gain access to prey. The research observed the behavior of octopuses during interspecific hunting events and discovered that they used their arms like fists to throw a punch at fish who might steal "their" food. Sometimes the octopuses were observed pulling punches even when there was not prey to be taken, which the researchers state represents one of three possibilities; that the octopuses reap future, as of yet unidentified, benefits from punching their coworkers; that they are defending themselves; or, quite simply, they're just spiteful jerks.
Interspecific hunting events see two or more species working together to score a meal. This kind of cooperation is common in nature, involving animals of all behavioral and anatomical complexities in a way that provides an immediate and direct benefit for its participating partners. Whether closely related or from two entirely different cuts of cloth, the merging of minds usually comes as a result of each participant having a unique skill which makes them a worthy ally when on the prowl.
One of the most famous examples of interspecific hunting is seen between moray eels and groupers who combine complementary hunting techniques to increase their chances of success. Noodly eels are perfect for scaring out prey from their hiding place between rock crevices, running straight into the jaws of hungry groupers. The collaboration is a sophisticated one, with footage which demonstrates the behaviors which recruit and guide each party to curate the hunt.
Groupers alongside swathes of other coral reef fishes are known to practice interspecific hunting with octopuses and these interactions, some lasting over an hour, can be between an octopus and several reef species at the same time. The octopuses pursue prey hiding among rock and coral crevices while the fish form a perimeter blocking those trying to escape.
In this new study, the researchers looked at octopus hunting events in Eilat, Israel, and El Quseir, in Egypt to see how they engaged in collaborative hunting with fish. As the hunting events played out before their eyes, the researchers noticed something curious. The octopuses were performing a swift, explosive motion with one arm directed at their hunting partners. To put it bluntly, they were punching fish to get first dibs on the food.
So, how does a fish respond to such an assault? "During these hunts at least, the fish seem resigned to getting punched even if that means getting displaced to a less advantageous position, or momentarily evicted from the group and then returning," wrote researcher on the study Eduardo Sampaio in an email to IFLScience. "However, we are now running quantitative analyses in hopes to better understand how previous and subsequent interactions differ between the octopus and the punched fish, and also how that affects the network of interactions in the group itself."
Did you know that octopuses sometimes take their battles out of the water? Just ask these crabs.