Thanks to NetGalley and the publisher for an advanced copy in exchange for an honest review.

Ahhh omg one of my new favorites this year for sure! I loved the author's writing style, and after reading this I am absolutely also going to get a tiny hydrophone like she did so I can listen to the ocean too. She explains how the physical structure of our ears prevents us from being able to hear the sounds of underwater as ocean life does. For example, invertebrates and some fish sense sound through particle movement rather than just pressure changes as we do. Sound waves also behave very differently (4.5 times faster!) in water than in the air, and we are simply not built to appreciate the richness of ocean sound. Did you know that when underwater, navy diving experiments have shown that sound probably does not even reach the eardrum but that hearing is instead through bone conduction?!

Not only does she go over a lot of the mechanics of sound waves and hearing in a very accessible way, she explains the physics of how sound works in the ocean. She explains the SOFAR channel, an especially sound-conductive layer in the ocean where sound can travel incredibly long distances. If you read and enjoyed Deep: Freediving, Renegade Science, and What the Ocean Tells Us about Ourselves by James Nestor, he goes into this as well and its relation to ocean mammal communication. If you liked that book at all, you would also really enjoy this one and vice versa!

So in addition to sound sensing, Kingdon covers sound making by ocean organisms as well. Fish have the widest variety of sound making structures of any vertebrate group! You can bet my YouTube history is now filled with things like "midshipman fish singing" now lol. She also of course gets into a lot of details of how whales and dolphins produce and hear sound, so if you are into cetaceans and their communication, then this book would be very interesting for you.

But this author seeks not only to discuss how sound works in the ocean and the many, many cool sounds produced by ocean animals, but also how the soundscape of the ocean is changing due to noise produced by the shipping industry and developments such as offshore wind farms or seabed mining. Ship noise is even still audible in the Mariana Trench- and some species are proving to be very sensitive to an increasingly loud ocean.