Sound waves to keep dolphins away from death by fishing nets

Morocco has decided to generalize the diffusion of sound waves in water to keep dolphins away from fishing nets, especially in the Mediterranean, the Moroccan Sea Research Institute said Monday in a release.

The method has already been tested and proved efficient off the Moroccan northern town of Al-Hoceima, the Institute said.

Developed in Tunisia, the method consists of emitting waves at the same pitch level as those of dauphins in a bid to jam the target image of the dauphins.

Large dolphins, known as negros for their black skin, are often found in the fishing nets. Their attacks of the catches usually entail loses and threaten their lives.

The negro dolphins attacks are said to be the major problem of sardine ships operating in the Mediterranean.

The mammals are very powerful, measuring 2.5 to 3.5 meters long. They usually attack in schools of five to six.