The Surprising Role of Whales in Climate Regulation and Ocean Health
What Does Whale Poop Have to Do with the Planet?
When you think about whales, you probably picture giant breaches, deep ocean dives, and soulful songs—but their poop might just be one of their most important superpowers.
That’s right: whale poo plays a crucial role in supporting marine ecosystems, boosting biodiversity, and even reducing carbon in the atmosphere.
In this blog, we’ll explore:
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How whale waste works as a fertiliser
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Why it matters for the carbon cycle
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How whale conservation supports climate health
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What recent science is revealing about this natural phenomenon
How Whale Poop Fertilises the Ocean
Unlike many marine animals, whales are vertical migrators—they dive deep to feed on krill and then return to the surface to breathe, socialise… and poop.
But this poop isn’t just waste—it’s packed with nutrients, especially iron and nitrogen, which are essential for phytoplankton growth.
How It Works:
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Whales consume krill and small fish in the deep ocean
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They excrete nutrient-rich waste near the surface
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This waste fertilises phytoplankton, the base of the marine food web
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Phytoplankton then absorb carbon dioxide during photosynthesis
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When plankton die, some carbon sinks to the ocean floor—removing it from the atmosphere
This process is known as the “whale pump”, and it helps cycle nutrients vertically, which supports marine life across all levels of the food chain.
Want to learn more about whale behaviours like diving and migration? Check out our Sydney Whale Science article.
Whale Poo and the Carbon Cycle
Let’s take a closer look at how whale waste is linked to climate regulation.
Phytoplankton absorb nearly one-third of the world’s carbon dioxide, making them critical players in the global carbon cycle. Without nutrients like those provided by whale poo, phytoplankton growth would be severely limited, especially in iron-deficient parts of the ocean like the Southern Ocean.
By increasing phytoplankton production, whales indirectly:
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Reduce atmospheric CO₂
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Support fish populations
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Enhance oxygen production (phytoplankton generate over 50% of the oxygen we breathe)
This is why scientists now refer to whales as “ecosystem engineers”. They don’t just live in the ocean—they help sustain its health and resilience.
The Whale Poo Feedback Loop
The more whales there are, the more they poop. The more they poop, the more plankton grow. The more plankton grow, the more carbon is absorbed. This creates a positive feedback loop that benefits the ocean and the atmosphere.
Here’s the simplified cycle:
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Whales feed → 2. Whales defecate → 3. Nutrients fertilise phytoplankton →
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Phytoplankton absorb CO₂ → 5. Carbon is stored in ocean sediment
Key Terms to Know:
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Whale Pump: The vertical mixing of nutrients by whales
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Biological Carbon Pump: The process of moving carbon from the surface to the deep ocean
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Ocean Fertilisation: The enrichment of surface waters with nutrients
Explore how the humpback whale migration supports ocean ecosystems on our Best Time to See Whales in Sydney blog.
How Modern Science Is Tracking Whale Poop
Scientists like Dr. Vanessa Pirotta (author of Humpback Highway) use drones to collect whale snot and waste, helping researchers study:
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Diet and health
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Hormone levels
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Population trends
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Microbial content in whale poo
This non-invasive method helps track how whales are influencing ocean ecosystems and how they may help mitigate climate change.
What Happens If Whale Populations Decline?
Historically, commercial whaling decimated global whale populations, particularly in the Southern Ocean. As whale numbers dropped, so did the amount of nutrient-rich waste entering the ocean.
A lower whale population means:
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Fewer nutrients available to phytoplankton
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Decreased carbon capture
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Less marine biodiversity
Rebuilding whale numbers can help restore lost ecosystem functions—including their role in carbon sequestration and fishery productivity.
Why Whale Conservation Matters for Climate
Conservation isn’t just about protecting whales for tourism or biodiversity—it’s a climate issue too.
By supporting whale populations, we help:
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Boost ocean health
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Strengthen the marine food web
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Increase the ocean’s capacity to regulate carbon
In other words, saving whales helps save the planet—from the surface to the seafloor.
Want to experience whales in action? Book your Barefoot Whale Watching tour and see these climate heroes up close.
Whale Watching and Ocean Awareness
Whale watching plays a powerful role in connecting people with ocean health. Seeing these giants in their natural habitat makes the science real—and inspires action.
At Barefoot Whale Watching Sydney, we’re proud to:
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Offer small-group tours with expert guides
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Share science-backed insights during each trip
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Promote eco-conscious marine tourism
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Foster a love of whales and the ocean in every guest
Meet our experienced marine crew and find out why we’re passionate about ocean education.
Final Splash: Small Creatures, Big Impact
Whale poo may not sound glamorous, but its impact is enormous. From nourishing microscopic plankton to removing carbon from the atmosphere, it’s one of nature’s most ingenious recycling systems.
As research continues to uncover the secrets of the sea, one thing is clear: every whale matters—not just for their beauty and behaviour, but for their role in protecting our shared planet.
