When Synthesizing Nitrogen Saved the Seabirds
In the mid-19th century, the world was flush with a new obsession: bird poop. Not just any poop, though — this was guano, nitrogen-rich excrement from seabirds, and it was as good as gold for farmers desperate to fertilize depleted soils. But beneath the surface of this miracle fertilizer was a deeply troubling story of ecological devastation and human exploitation that would only end when a new technology displaced it.
The White Gold Rush (for Bird Poop)
Before the invention of synthetic nitrogen fertilizer, guano was among the most prized commodities in the world. The best deposits came from remote Pacific islands where seabirds had nested for millennia, layering the ground with meters-thick blankets of excrement. As agriculture intensified and global populations swelled, demand for guano exploded.
In 1856, the United States even passed the Guano Islands Act, a little-known law that allowed American citizens to claim any uninhabited island with guano deposits for the U.S. — essentially a poop-based version of manifest destiny. Over the next several decades, the U.S. laid claim to nearly 100 guano-rich islands, mostly in the Pacific and Caribbean. These remote outposts became extraction zones, where laborers — often enslaved, coerced, or working under horrific conditions — were forced to shovel guano under the blazing sun for export back to the mainland. There was even a labor rebellion on Navassa Island in 1889, where workers protested brutal treatment, underscoring the grim reality of guano extraction.
It wasn’t just the human cost that was staggering. Entire island ecosystems were disrupted. Seabird populations were decimated, their habitats destroyed in the frenzy of extraction. Some species still haven’t recovered. And yet, guano was so vital that in the 1860s, Britain and Peru even went to war in part over access to it.
By the turn of the 20th century, panic began to set in. Guano supplies were dwindling. Newspapers ran pieces warning of an agricultural apocalypse without it. There was even an 1857 article entitled The Guano Crisis.
That question had an answer — but it came not from the ocean, but the lab.
Technology to the Rescue
In 1909, as detailed in The Alchemy of Air, German chemist Fritz Haber developed a method for capturing nitrogen from the air and converting it into ammonia, a form of nitrogen plants can absorb. It was a breakthrough so revolutionary that his colleague Carl Bosch scaled it up for industrial use, giving rise to what we now call the Haber-Bosch process. Suddenly, we no longer needed to harvest bird poop to feed our crops — we could create synthetic fertilizer in a factory.
This wasn’t just a scientific triumph; it was a moral one, too. With the invention of synthetic nitrogen, agriculture was liberated from a supply chain built on ecological destruction and human bondage. No more strip-mining seabird sanctuaries. No more enslaved laborers inhaling toxic dust on isolated atolls.
Of course, the story doesn’t end there. Today, the widespread use of synthetic nitrogen comes with its own set of environmental consequences — eutrophication, nitrous oxide emissions, and more. But it’s important to remember what it replaced. For all its faults, the Haber-Bosch process helped spare both wildlife and people from a deeply unethical system. (Sidenote: In the 21st century, demand for organic produce — which disallows human-made nitrogen fertilizer — caused demand for Peruvian guano to once again increase.)
Technology: The Great Liberator of Animals
It’s a familiar pattern, actually: we create technologies that displace old, often cruel practices. Whaling gave way to kerosene. Ivory combs yielded to plastic. Rennet from baby calves was replaced by recombinant enzymes. And yes, guano — harvested on the backs of slaves and at the expense of seabird ecosystems — was replaced by a synthetic molecule that changed agriculture forever.
As we think about the next steps in sustainable food production — whether it’s mycoprotein grown in fermentation tanks or meat cultivated without animals — it’s worth asking: What old cruelties are we still accepting simply because we haven’t invented our way out of them yet?
The future of food isn’t just about feeding more people — it’s about feeding them more ethically. And just as we once believed that the world would collapse without guano, today many believe we can’t feed the world without confining and slaughtering billions of animals. But history shows us otherwise. With enough ingenuity, we don’t just find alternatives — we find better ones.
Paul Shapiro is the CEO of The Better Meat Co., the author of the national bestseller Clean Meat: How Growing Meat Without Animals Will Revolutionize Dinner and the World, a five-time TEDx speaker, and the host of the Business for Good Podcast. In 2023, he was named a Most Admired CEO by the Sacramento Business Journal.
