The sounds of sex orgies fish stun the dolphins, say scientists

© Ministry of natural resources and ecology of the Russian Federation. Igor Selenocyanate reserve. Mass spawning of sockeye salmon in Kuril lakeThe sounds of sex orgies fish stun the dolphins, say scientists© Ministry of natural resources and ecology of the Russian Federation. Igor Shpilenok

. Spawning one of the American marine fish was so loud that it sounds literally deafen the dolphins and any other sea predators dare to approach the «Orgy» of these fish, according to a paper published in the journal Biology Letters.

«These spawning can be called one of the biggest events on Earth which involve animals. Moreover, it is the loudest sounds that ever issued fish on our planet. Even from a distance the place where these fish mate, sounds like there is a crowded football stadium, or a very loud hive of bees,» says Timothy Rowell (Rowell Timothy) from the University of California at San Diego (USA), whose words are quoted by the Internet portal

Many land and sea animals use very unusual methods of attracting attention of the opposite sex, in addition to their appearance. For example, many tropical frogs climb into hollow trees and use them to enhance their mating serenades, and elephants communicate with females and convey information about yourself across large distances with the aid of the stamping.

One of the most publicised examples of such behaviour, as noted by Rowell, is spawning Zander slabs – North American marine fish that have learned to use their swim bladder in order to reproduce a series of very loud and sharp sounds.

How jokes Rowell, even one Croaker can give marriage «Serenade», resembling machine-gun fire on their volume and the overall sound, and the great mass of these fish, a gathering every spring at the mouth of the Colorado river off the coast of California, arrange superloud «concert».

These sounds attract the attention of not only females, but also the fishermen whose hull boats literally start to vibrate after the start of the breeding season for the slabs. Scientists are interested in, you can hear the sounds of dolphins, sea lions and other predators, and whether their ears to withstand such a powerful load.

For this Rowell and his colleagues made several expeditions to the spawning of the croakers off the coast of California and recorded their courtship «songs» and the sounds of mating, using underwater microphones. Analysis of these records quickly showed that none of the animals likely would be unable to withstand such loads – the power of sound in some cases exceed 190 decibels, significantly louder than the roar of the turbine jet.

The consequences for the person listening to such a «concert» about the same as if you near his ears exploded grenade or small bomb. In other words, if the «Orgy» of croakers will try to interfere with a Dolphin or a seal, they almost immediately go deaf and will begin to experience severe pain.

Interestingly, Rowell and his colleagues often notice groups of dolphins and sea lions, plying a short distance from fish spawning sites. It is not clear whether they’re trying to get inside the accumulation of croakers or just catch those males and females who go with to this point from all corners of the Pacific.

Why fish make such a noise? As scientists believe, this heavy duty «choir» is the product of sexual selection, which forced the ancestors of the need to develop more and more loud sounds to attract females in a crowded breeding ground where there are millions of competitors and where there’s nothing to see.