Sound is a vital communication tool for many animals, but even more so for marine life. Life under the water has evolved over thousands of years to rely almost entirely on sound for survival cues. This is because the density of water allows sound to propagate efficiently, which is why whale song can travel across entire ocean basins. Conversely, light waves cannot travel very far at all. So without the ability to see more than a few metres ahead, marine life must use sound instead to attract a mate, ward off predators, stun prey, and identify suitable habitats.

And yet, those vital sounds are having to compete under the ocean’s surface against a huge variety of man-made sounds. Since the industrial revolution, those marine-life calls are increasingly drowned out by the pulses and drones of ships, sonar, and more. And it is the whole ocean ecosystem that is affected - from tiny zooplankton to the enormous blue whale.

Zoologist and wildlife cameraman Hamza Yassin speaks to scientists to understand exactly how our noise pollution affects these animals. Hamza unveils fascinating experiments that reveal how noise can affect every aspect of life, from reproduction to physical condition.

Hamza journeys under the sea to listen to the ocean soundscape, using genuine underwater recordings from scientists across the world. He asks what potential solutions may restore peace to the ecosystem and whether the quieter world that emerged from the recent pandemic offers any insights to build on.

Presenter: Hamza Yassin

Producer: Meera Kumar

Executive Producer: Anishka Sharma

A Whistledown Production.

Commissioned in association with the Multitrack Audio Producers Fellowship.

With thanks to the following for sharing their field recordings for use in this programme:

BarcelonaTech (UPC), Eric Parmentier, Isla Davidson, Laboratory of Applied Bioacoustics (LAB), Listen to the Deep Ocean (LIDO), Madre Agua Colombia (via Mar Palanca), Marine Conservation Research/International Fund for Animal Welfare (IFAW), Michel André, Daniel Noreña at Los Andes University (Susana Caballero, co-advisor with Kerri Seger) working with PHySIColombia, Rob McCauley, Sarika Cullis-Suzuki, Steve Simpson, Technical University of Catalonia, Tim Gordon, Dr. Jorge Urban's lab at Universidad Autónoma de Baja California Sur (UABCS).