Why whale poo is good for the oceans... and us

WHALES: GARDENERS OF THE OCEANS (W/O PREROLL)

We thought these whales were our competitors, feeding off the same fish we rely on. But now we know how much they benefit our lives, in an unusual manner.

Oceans envelop three-quarters of our planet’s surface. The survival of three billion people depends on their incredible bounty. Only now are we discovering how the ocean’s largest inhabitants are helping to enhance this.

Just like on land, most of life in the ocean ultimately runs off plants and photosynthesis. In the ocean, the plants that live there are microscopic, called phytoplankton. The whole ocean ecosystem is driven by these plants that grow on the surface – and as phytoplankton produce half of the oxygen that we breathe, we rely on them too.

When phytoplankton use up all the nutrients in the water, this vital growth goes into decline. But nature provides an unexpected lifeline, in the form of whale excrement. Whales excrete near the surface, releasing huge amounts of nutrients. It’s the perfect place to plant fertiliser to grow phytoplankton, at the level where there’s the most amount of sun and oxygen.

In this film, wildlife cameraman Doug Allan, Dr M Sanjayan and Stephanie Wear at The Nature Conservancy, and Dr Joe Roman, conservation biologist at Duke University, describe how this is changing our view of whales. We thought that they were our competitors because they consumed the same fish that we relied on. Now we know they are our allies by recycling nutrients, helping sustain our ocean’s precious plantlife.

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