Octopuses throw objects at one another, researchers observe

They hunt alone and are prone to a scrap. The cloud of silt, algae and shells that the octopuses hurl appears to be another arm to their behavior.

In order to get the debris out of the front arms and web, the researchers used water that was ejected from the scepter and moved it between the rear arms.

According to the team, the throws appear to be used by the octopuses for den cleaning, or throwing away shells, but they have also recorded the creatures hitting other octopuses with material in what appear to be deliberate strikes.

The first author of the research said the behavior is surprising.

Throwing objects that have been gathered and held is rare in the animal kingdom. He said that it is difficult to propel an object under water.

They recorded more than 21 hours of video in the Jervis Bay off the south coast of New South Wales, Australia using underwater stationary cameras.

The males and females were recording their actions. The majority of the hurls were accounted for by two females.

The team reported that 32% of throws were related to the cleaning out of the dens of the animals, while 8% were related to eating.

More than half of the recorded throws happened within two minutes of an interaction between one or both of the animals.

silt as the main material was involved in these interactions as well as another action such as den cleaning. More than one third of the throws involved hitting another animal.

Such strikes seem to be deliberate. The team found that those that were throwing with high energy and those that were darker in colour were more likely to hit another one.

Darker colors are associated with more aggressive behaviors, according to the team.

In an unusual case, the team reported that a shell was flung by an arm and hit another animal.

The recordings from 2015, as well as other footage, show instances of the cephalopods making multiple throws within a time period. On some occasions, those in the line of fire appeared to raise one of their arms before the throw to make sure they were ready.

The team said that the footage did not show the behavior of the octopuses starting a fight, or returning fire, while in some instances, throws were made into empty space. They write that it is possible that an interaction between an animal and another could result in a hit.

The strikes could have something to do with it. He thinks a lot of it is an assertion of personal space. Females have thrown material at males who have been trying to mate with them.