Noise pollution is less well known and less publicized than plastic or chemical/industrial pollution. Yet sound travels far and better in water. Hearing is the means of communication and localization most used by marine mammals: whales, dolphins, belugas, etc. Hearing is to marine mammals what sight is to man. So the noise generated by maritime traffic can make them "blind": communicating with each other and reproducing, spotting prey, navigating and organizing migration are all fundamental behaviors that noise pollution modifies or even prevents. It is estimated that noise pollution doubles every 10 years, and is a new factor endangering these animals.

What does the sound environment look like?

Want to hear what it sounds like? Here's a great illustration of mammal sounds to help you identify them the next time you dive. OK, it's Alaska! I suggest you listen to the song of the Beluga, sometimes compared to the "canary of the seas".

For the more scientific among you, an in-depth study summarizes the literature on the impact of shipping on cetaceans. Click here.

Alongside this little blog on acoustics, another exciting initiative in the study of cetaceans is being carried out by a small American association, OceanAlliance: thanks to a drone, scientists will be able to analyze the breath of a humpback whale. The expedition blog is here.

COVID-19 benefits marine life

The slowdown in the economy due to COVID-19 has significantly reduced this noise pollution: what silence, what rest! Marine mammals can be found in the vicinity of normally deserted ports. Collisions with ships, particularly in the area of the Pelagos sanctuary, the Mediterranean offshore marine park, are on the decline. All national marine parks have observed the return of certain species to their waters: the absence of man and his boats frees up space for nature and brings calm. It will only have taken a couple of weeks for nature to reclaim its rights: this gives us confidence for the future. We can still make up for our mistakes and erase the scars of uncontrolled industrial development.