According to scientists who recorded the footage, octopuses caught on film punching fish out of spite.
Researchers at the University of Lisbon in Portugal said the ‘punching’ occurred while hunting where the octopuses and fish hunted side by side.
Biologist Eduardo Sampaio said that in some cases the ‘thrusts’ were motivated by practical gain, such as stealing prey from a fish.
But in several cases, the punches seemed to be delivered to ‘impose charges’ on ‘misbehaving’ fish – an emotion researchers likened to ‘resentment’ in humans.
This is when an octopus (pictured) randomly hits a fish ‘out of spite’ while chasing next to them
You see the octopus move towards the fish and knock them out of the way with its tentacle. Pictured: The octopus just before its attack
The images show octopuses moving towards the fish and knocking them out of the way with their tentacles.
The two species often hunt together and use each other’s hunting strategy to their advantage, but it is rare to see an octopus hitting a fish.
While this bizarre behavior sometimes comes from resentment, it could also be to keep his hunting mates in line as the competition gets fierce, researchers claim. Any misbehaving fish trying to steal prey can also take a punch.
“Octopuses and fish are known to hunt together, using the morphology and hunting strategy of the other,” explains marine biologist Eduardo Sampaio, a co-author of the study published in the Ecology Journal.
“As multiple partners join, a complex network is created in which investment and payout can be unbalanced, creating partner control mechanisms.”
He continued, “We have found several contexts where these bumps occur, including situations where immediate benefits are achievable, but most interesting in other contexts where they are not.”
The team of researchers, led by Mr Sampaio, from the Marine and Environmental Sciences Center of the University of Lisbon in Portugal, filmed the octopuses off the coast of El Qusier, Egypt and Eilat, Israel between 2018 and 2019.
An octopus (center) approaches a fish before striking it with its tentacle
The various octopuses were engaged in ‘active movement’ of their partner fish in the Red Sea during the joint hunt. For the octopus, punching serves as a partner control mechanism.
“To do this, the octopus performs a rapid, explosive movement with one arm aimed at a specific fishing partner, which we call punching,” the researchers said.
The team recorded punches targeting a variety of fish species, from squirrel fish, blacktip and lyre-tailed bass to yellow saddle.
“These multiple observations with different octopuses at different locations suggest that punching serves a concrete purpose in interspecific interactions,” the researchers added.
While this bizarre behavior sometimes comes from resentment, it could also be to keep his hunting mates in line as the competition gets fierce, researchers claim. Any misbehaving fish trying to steal prey can also take a punch
They assume that the punching is used to control the other fish during the hunt – either to keep them away from prey or to drive them out of the group completely.
In cases where fish are opportunists and try to reap the benefits of the hunt without contributing, the octopus may hit the fish because of simple competition, the researchers claimed.
But on two occasions, an octopus hit a fish to retrieve prey.
In these cases, two different theoretical scenarios are possible. In the first case, the benefits are completely ignored by the octopus, and punching is a hateful behavior used to give the fish a prize, ” the researchers said.
They also think that the spanking may just be a “form of aggression” against a misbehaving fish.
The team is conducting further research to understand why this bizarre behavior occurs.