Whales Are Climate’s Secret Architects

Every dive, every plume, every death in the deep steadies our climate. This is how whales keep the world alive.

Whales are more than ocean giants. They fertilise plankton, move nutrients across entire seas, and lock carbon away for centuries when they die. Industrial whaling broke this planetary system, but recovery has already begun. This piece blends science and personal encounters to show how whales act as climate’s secret architects, and why protecting them may be one of the most powerful climate solutions we have.

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It was the summer of 2010, and the Atlantic was cold enough to sting. Salt on my lips, mask fogging, the hiss of my own breath loud in my ears. I floated in silence between Tenerife and La Gomera, the ocean stretching deep and endless below.

Then they appeared.

A family of pilot whales, slipping out of the blue like shadows. Two broke away and swam toward me. I forced myself to stay still. My chest ached with held breath. Then, impossibly close, one turned just enough for its eye to meet mine.

Time bent. The water muffled everything except that gaze. Bright, unblinking, patient. For a moment it felt as if the ocean itself had paused, waiting for me to understand.

That moment was caught on film. Here is the encounter as it happened.

I have seen many whales since. Humpbacks breaching gracefully off Vancouver. Orcas in Monterey Bay tossing a bird between them for an hour, passing it back and forth like a game. A pilot whale carrying her dead calf in her mouth, unwilling to let go. Each moment has stayed with me. Yet that first eye contact remains the anchor. That moment felt like being acknowledged by the ocean itself

The Gardeners of the Sea

Whales are not simply inhabitants of the ocean. They are gardeners. Every dive, every breath, every plume of waste moves nutrients in ways that shape life itself.

I remember the first time I saw a whale’s faeces on a whale watching trip. A brown plume trailed behind, suspended in the water like smoke. At the time it looked like little more than a mess. Only later, when I began working at Whale and Dolphin Conservation, where I lead the campaigns against commercial whaling and captivity, did I learn what it truly was. Fertiliser. A gift to the plankton floating in the sunlit layer of the sea.

Marine ecologist Joe Roman calculated that in the Gulf of Maine, whales and seals once released over 23,000 tonnes of nitrogen per year. That’s more than all the rivers flowing into the Gulf combined. Rivers are the ocean’s traditional fertiliser pipelines, carrying nutrients from land into coastal waters where plankton blooms begin. To realise that whales alone outpaced that entire system is staggering. Imagine thousands of fertiliser trucks tipping their load into the sea each year, only these trucks swam.

Many whales feed in the dark, cold depths and return to the surface to breathe. There, they release plumes rich with nitrogen, phosphorus, and iron. Unlike the dense pellets of smaller animals that sink quickly, whale faeces spreads as a buoyant cloud, staying near the light where phytoplankton can use it. In the Southern Ocean, sperm whale plumes carry iron so concentrated that it is like tipping manure into a starving field.

That fertiliser sparks phytoplankton blooms, vast, swirling fields of microscopic plants in the sunlit ocean. These blooms are not just food. They are forests of the sea, drawing carbon out of the sky, feeding krill and fish, and rippling upward to sustain seabirds, seals, and us.

Whalers once claimed whales stole our fish. The evidence shows the opposite. Seas with more whales have more plankton. More plankton mean more forage fish. More forage fish mean healthier seas.

Whales do not take away. They multiply.

The Great Conveyor

The whale pump works vertically. The whale conveyor works horizontally.

Every year, humpbacks, fins and blues embark on migrations that span oceans. They gorge on krill in polar seas, then travel thousands of miles to breed in the tropics. Along the way they shed skin, release urine and leave trails of nutrients in waters that would otherwise remain barren.

Andrew Pershing and colleagues modelled what the ocean looked like before industrial whaling. In the Gulf of California, pre-whaling numbers of blue whales could have increased phytoplankton growth by 15% every year. That is the oceanic equivalent of planting tens of thousands of hectares of forest in a desert.

Whales fertilise the ocean in life, in motion, in breath. Yet their greatest gift often comes at the end.

If you’ve read this far, you know whales are more than ocean giants, they are climate’s secret architects. The next part of this piece goes deeper: grief, collapse and the return of the giants. This work is made possible by Ocean Rising’s paid subscribers and Founding Members. You can join them, and unlock the full article today, with a free 7-day trial.