Do wind turbines in the sea scare whales?
“It doesn't end up often in the newspapers, but it can have serious consequences - Francesca Santoro, program specialist at Unesco explained to sportsgaming.win - Let's think about the whales that run aground on our beaches: one of the hypotheses to explain the phenomenon is that the auditory apparatus of the cetaceans, also necessary for their orientation, has been put out of action by the noise ".
Underwater visibility is reduced to a few hundred meters, but the sounds are able to travel for thousands of kilometers; this physical property of acoustic waves is exploited by species that rely on hearing to orient themselves.
But from fishing to commercial traffic, from submarine military exercises to drilling for companies looking for rare metals, the list of elements capable of interfering with this process is long. A year ago Science published an article born from the collaboration of twenty-five scientists from all over the world and with the emblematic title: "The soundscape of the ocean at the time of the Anthropocene". The conclusion of the study conducted by Professor Carlos Duarte of Kaust University in Thuwal, Saudi Arabia, is that the marine ecosystem is under immense stress nowadays compared to the pre-industrial era, and the negative impact of human activities on life below. water appears indisputable.
There is no evidence that pollution causes the death of fish and larvae, but there are some that the noise modifies the behavior and habits of those who live in the seas - especially mammals - and causes damage to them auditory system.
The impact of offshore wind turbines To the already large number of activities that produce ocean noise, in recent years there have also been added wind turbines built in the sea to obtain clean energy from the wind - a solution that allows to avoid the visual impact that these infrastructures have on the mainland.
In Italy, in Taranto, the first plant in the Mediterranean was inaugurated in April: a large-scale project, which includes ten turbines located one hundred meters from the coast , for a total power of thirty megawatts. Beleolico, this is the name, is able to provide for the annual energy needs of sixty thousand people.
Renexia, the construction company, had already commissioned a pre-construction study to assess the impact of the works - for example that of the pile-driving ships, in charge of setting the structures to the seabed. But now that the plant is in operation (and will remain operational for at least twenty-five years), the company intends to start a three-year monitoring. To do so, he offered a scholarship won by Serena Gatto, a young graduate in marine biology who will conduct the research.
Gatto discussed in March a thesis on noise pollution in the abyss. Now, from the deep northeast - she is Friulian, of Venetian origins - she will move to the Apulian city.
"This is the first study to monitor the impact of this type of structures, and for this we are particularly grateful to society which financed it, ”says the researcher. "We want to find out if the vibrations produced by wind turbines can influence the sound production of cetaceans, and therefore evaluate their impact on mammals".
The Jonian Dolphin Conservation, a local organization committed to supporting Gatto, supports protection of dolphins and cetaceans in general. “They asked me to start - resumes the researcher: they had a great deal of material collected over the course of ten years which, however, had to be analyzed. So I learned to sample the sounds of the sea: then I analyze the spectrogram, that is the representation of intensity as a function of time and frequency ". By cataloging the data, the impact of the blades will be assessed, in an analysis necessary for any mitigation interventions. Furthermore, the idea is to define "good practices" to be used in the Mediterranean for offshore plants.
The area of the Gulf of Taranto has always been very busy. In addition to the commercial traffic, there are the exercises of the Navy, which has a base here, and uses the canyon that runs from Italy to Greece for submarine exercises. "We need to find a meeting point between the needs of man and those of the ecosystem, creating a blue oasis," says Gatto. The difference compared to a marine protected area? "In this case, navigation is not prohibited but there is a set of protection rules to follow". A protection that must be supranational: "From the fins of sperm whales, a sort of identity card of the species, it was realized that the same specimens spend one season in Italy and the other near the Hellenic territory: to achieve the conservation objectives, therefore broad agreements ".
" Citizen science "But the sea trips are expensive, and a small organization struggles to bear the costs, starting with those of fuel. This is why Jonian Dolphin Conservation finances them through citizen science activities. "Through the Researcher project for a day we involve tourists, schools and local people in our activities" says Carmelo Fanizza, operational director of the association. "We have two catamarans on which it is possible to embark every day: those who board , helps our biologists to collect data which are then analyzed: coordinates, species sighted, number of specimens, behavior ". Then there are more complex activities: “For example, we collect acoustic data with hydrophones and skin samples using a skin scrub. This allows us to count on a constant form of financing ”. For those who get on the boat, on the other hand, the ticket allows you to try an interesting experience that is able, why not, to discover hidden passions. "I too - reveals Gatto - was struck by a boat trip when I was a child".
