This article was originally featured on Hakai Magazine, an online publication about science and society in coastal ecosystems. Read more stories like this at hakaimagazine.com.
In the 20th century, people’s demand for whale blubber and baleen drove industrial whalers to kill roughly three million whales—a whopping 99 percent of the world’s whale population. The intensive hunting not only devastated ocean ecosystems, it also dismantled a key mechanism for moving nutrients through marine food webs. As a result, the whalers built up an ecological debt that we have yet to pay off.
As research over the past several decades has shown, whales play a critical role in bolstering ocean ecosystems. Many whale species feed in the depths of the ocean where prey is plentiful, but where the water pressure is immense. At depth, says David King, a chemist at the University of Cambridge in England, many whales find that “their orifices are jammed shut.” So, to properly relieve themselves, they head toward the surface, where their defecations bring a steady flow of nutrients—such as iron, nitrogen, and phosphorus—to a part of the sea where they’re typically in short supply.
The real ecological magic happens when sunlight strikes a cloud of whale crap. This can trigger a bloom of phytoplankton—the base of most marine food chains. “This happens very quickly,” says King. “Three to four days after the whales have visited the surface, you’ll get a great green area—maybe a few thousand square kilometers [in size].”
Plumes of whale poop, says Heidi Pearson, a marine biologist at the University of Alaska Southeast, contain nutrient concentrations three to seven times higher than typical seawater: “they make the ocean more productive in general.” Through photosynthesis, all of this phytoplankton gobbles up roughly 22 megatonnes of carbon dioxide each year—the amount emitted by about 4.8 million vehicles. When the phytoplankton die and sink to the seafloor, some of this carbon is locked away long term.
But the legacy of industrial whaling means there are far fewer whales patrolling the ocean than there used to be, which means fewer whales pooping near the surface, less nutrient cycling, and less carbon sequestration. That is precisely why marine scientist Edwina Tanner and a small group of collaborators at the WhaleX Foundation are attempting to create synthetic whale poop.
Comprised largely of nitrogen with a sprinkling of phosphorous and trace elements such as silica and iron, the WhaleX team is attempting to design fake feces that accurately replicates the original in both form and function. Compared with other efforts to tackle soaring atmospheric carbon dioxide concentrations, Tanner says, “this is a more holistic approach. It’s restoring ecosystems, growing fisheries, and amplifying natural methods.”
In December 2021, Tanner and her team released 300 liters—equivalent to one whale plume—of their specially formulated fake feces into the Tasman Sea off Australia’s eastern coast. Now WhaleX is gearing up to disperse five whale plumes worth of nutrient-rich slop into the Tasman Sea early next year. Only this time around, they’ll be trialing a new technique.
Where WhaleX’s first test involved pumping the artificial poo directly into the sea from tanks aboard a boat, in 2025 the team will use two or three “biopods”—five-meter-long cylinders filled with seawater and fake feces. After allowing phytoplankton to grow in a nutrient-rich bath inside the biopods for four to seven days, they will release the contents into the ocean.
Not only will these hardy plastic containers help keep the nutrients afloat on the ocean’s surface, they’ll also allow WhaleX to accurately measure how well the microalgae have grown and to calculate the amount of carbon captured in the process. “When we did our first experiment, everything dispersed, and there was no way to follow the [phytoplankton] growth,” explains Tanner.
Scientific and technical challenges aside, there are legal considerations, too. Although WhaleX has approval from Australia’s Department of Agriculture, Water, and the Environment to conduct tests within the nation’s waters, expanding overseas is another matter. Public appetite is also of concern. People sometimes associate phytoplankton with harmful algal blooms rather than with something that might be helpful for ocean health, says Tanner. “Historically, people have been a little bit wary of the word geoengineering and fertilization, but I think it’s become more acceptable over the years,” she says. Yet that hesitancy is one reason why WhaleX is mindful about not expanding too quickly.
WhaleX, though, is not the only project attempting to produce the perfect poo. The international Marine Biomass Regeneration project, headed by King at Cambridge, is also planning to test two new recipes by scattering them on the surfaces of “all the deep oceans of the world.”
Unlike WhaleX, which uses a liquid nutrient solution, King’s approach involves scattering the sea’s surface with nutrient-rich dust mixed with baked rice husks—an additive designed to keep the nutrients near the ocean’s surface for as long as possible. In their upcoming trials, King and his colleagues plan to distribute dust drawn from the Hunga Tonga–Hunga Ha‘apai volcano in Tonga, which erupted in 2022, and from Greenland, where heavy ice sheets grinding on granite bedrock yield an ultrafine, nutrient-rich powder. Previously, scientists have seen both kinds of dust triggering phytoplankton blooms—a clue, King says, that they’re “of the right nutrient content.”
If the experiments prove successful, King’s team hopes to take the artificial whale poop to Tonga and Tuvalu—two Pacific Island nations where local leaders have already expressed interest in using the approach to try to counteract the local decline of tuna and other important fish.
“We believe that if we can imitate the function of whale poo, we can—over perhaps a 40- or 50-year period—return the ocean’s fish, mammal, and crustacean populations back to where they were 400 years ago,” says King.
WhaleX has similarly big dreams. Their end goal is to apply their fake feces to 300 nutrient-poor, low-productivity sites around the world—dead zones also known as ocean deserts—to help remove up to 1.5 billion tonnes of carbon dioxide each year.
“It’s a flashy idea,” says Pearson, who isn’t involved in either effort. Experiments with synthetic whale poo, she says, hold great potential for capturing carbon and giving a vital kick to the base of the marine food chain. That said, “there are still a lot of unknowns,” she says, such as how much carbon is sequestered at depth, as well as the amount of nutrients actually making it into the food web.
Joe Roman, a conservation biologist at the University of Vermont, flags other concerns. One is how nutrient fertilization will change the chemistry of the deep sea. “It will be essential to examine ecological responses from the surface waters to the ocean floor before it’s adapted on a broad scale,” he says.
“There are definitely some challenges before we scale up,” Tanner admits. Aside from purely scientific concerns, the organization is also facing issues around governance, she says.
For instance, the London Convention—an international law that regulates what materials can be discharged into the sea—currently bars large-scale experiments with fake whale poop. For these projects to expand, scientists would have to prove that the substance has “no deleterious effect” on marine ecosystems, says King.
But if they succeed, the mock whale muck would be a welcome addition to the world’s carbon drawdown toolbox, says Pearson. “Every little bit helps,” she says. “I always applaud efforts of human innovation that look to nature because nature has always figured it out first—and best—after years of evolution.”
This article first appeared in Hakai Magazine and is republished here with permission.
