The fiery head of the parrot fish

Scientists were astonished when they first witnessed the "fiery" headmatch of parrot fish in the North Pacific.

>>>Video: The "fiery" head war of parrot fish

The strange sound like the sound of gunshots in the water suddenly came out when a group of scientists from the Beaufort Laboratory (USA) were diving in the North Pacific Sea, off Wake Atoll Atoll. It turned out, it was the voice of the unprecedented head-to-head fight of parrot fish living in the giant coral reef here.

A male parrot fish with wounds on the body
shows that he has just experienced a head-to-head fight

This parrot species, the scientific name Bolbometopon muricatum has a very large head, swollen, puffy lips and slightly pinkish face. Adult parrotfish can reach up to 1.3m long and weigh 46kg.

During the summer of 2011, for about 100 hours of diving, these scientists witnessed a lot of head-to-head attacks of this fish off Wake Atoll Island. Roldan Muñoz, a member of the research team, said on Live Science: "The sound they make when fighting is like someone shooting a gun right in the ear."

The recorded image shows that the male fish swims straight to its opponent until the two sides bump into each other. After this very painful collision, one will immediately swim in a semicircle to bite the other's tail and side. After that, they parted, and then rammed their heads together.

The team observed that most wars occur during the day and at the spawning place. So they surmised that choosing a partner made their heads swell up and rushed into their opponents.'We think that males rammed their heads together to show superiority to their opponents and gain access to the territory which was then used to call their children into mating.'

But why is such an aggressive and noisy act yet known? According to scientists, such behaviors are the result of competition for mating rights of males, so it can only happen in areas where fish density is too high.