Michel André: “The noise level in the sea is that of a bar, planes that pass and a train that does not stop”

—If what he listens to in his laboratory is what is heard in this exhibition, he must have the most relaxing work in the world.

—It are the sounds that are heard without human intervention. Then there are less pleasant noises.

—What is heard in the closest buoys of the 150 that monitors?

—The sound inside the water is spread at a much higher speed than in the air and a much higher distance. You can capture sounds that produce hundreds of kilometers further. Obviously closer to human activities there will be more artificial noises, and closer to a population of whales, dolphins, crustaceans or mussels, you will have more natural sounds. That forms a sound landscape that has been in harmony for millions of years. In the last 80, 100 years, we have produced noise massively without knowing that it could contaminate. When they began to see variations of ketás and effects in invertebrates, we realized that these noises could have a serious consequence.

—What are the effects of marine noise, beyond the vegetables?

—When we started, we thought that the species that were going to suffer this noise were those that use acoustic sound or actively acoustic information, such as cetaceans. For 20 years, our group and others concentrate on understanding the acoustic sensitivity of the 90 species of cetaceans that exist. But our laboratory, in 2011, found that marine invertebrates [crustáceos, cefalópodos, medusas, corales…]which are these species that lack ears, are sensitive to the mechanical aspect of that sound, to the vibratory appearance, which is the second component of sound. And when they are exposed they present the same acoustic traumas as the animals that hear the sounds. This completely changed the perspective of the impact of sound sources. In 2021 we found that the Mediterranean plants, the posidonia, when they are exposed to artificial noise sources also have traumas that are incompatible with their life. All links in life in the ocean suffer from this pollution.

“What do you mean with acoustic trauma?” Can you explain it?

“If we think about the effects of noise, we can categorize them into three.” The least importance is and that is already lethal is the one that masks information that is vital. In the sea, the only communication support is the sound. Therefore the masking of information can endanger animals. On the other hand, the worst is the source of such intensity that the wave associated with noise is lethal. And between the two, there is the sound that if the exposure is maintained, reaches a permanent pathology that makes you lose the ability to capture or extract sound information. And this makes you deaf to these frequencies.

—What noise generates automatic death?

—The level of sources due to human activity, those of more intensity are oil prospecting, the construction of wind farms and military maneuvers.

—In the Mediterranean, what could we compare the level of noise we have introduced? Is it like living with a bar under home?

“Well, it’s not just a bar.” It would be a bar, airplanes that pass permanently, a train without stopping by our side, continuous vibrations. This is the reality of the inhabitants of the sea, but with the difference that we can isolate ourselves, we have houses, we can put caps … in the sea you cannot. And the second difference is that we can live within a noise environment, we can see, we can communicate … They are impossible. They have no escape.

“Since she began studying noise pollution, has you improved the noise of the ships?”

“No, what has improved is consciousness and knowledge.” A design of the blades of the propellers is being studied so that they fall less [un proceso por el que producen unas microburbujas que cuando explotan hacen mucho ruido]without consuming more and without being less fast. When the current fleet is removed within ten years we will have slightly more silent ships. I think it will be late, but at least there is this effort.

—And establishing cetacean runners is used for something at the level of noise?

“The sea has no borders and the sounds travel much further than in any other channel.” The cetaceans, with the knowledge we have today, are the ones that probably suffer less from this pollution. Because? Because they have protection mechanisms against high intensity acoustic sources and have the ability to move away very quickly from an area. Therefore the dose of sound they receive, of frequencies, of duration and intensity is much less than that of invertebrates, which are the corals, the crustaceans, the cephalopods, the jellyfish … all these species move little, some some Nothing, and the impact is much greater. When the idea of ​​a corridor is taken into account, neither the time nor space scale is taken into account and neither these species suffer from this pollution.

—In Spain we will begin to display marine wind, floating. Do we know enough about its impact?

“We start, because recently this technology is underway.” It is very important that tests are done and above all put some monitoring mechanisms to see to what extent the construction affects the environment.

“Is it in favor of studying it while implanted, and not paralyzing construction?”

“Yes, we can’t go against everything that is being done.” We are as a society responsible for any human activity we have. Winding parks have an alternative to the energies that we know they harm.

“And with underwater mining?”

“It’s a serious attack on ecosystems.” If they started as they want to do, without any impact monitoring guarantee, we would end up with all the underwater balance at a speed never seen in the history of the human being.

“Why have we paid so little attention to noise pollution in the sea?”

“Because we don’t hear it.” If we are on the beach and we enter the sea, we say, ‘oh, what relaxation’, I no longer hear the screams. But if we were able to hear in the water, it would be much worse than we heard on the beach, we would not want to go.