Whales & Carbon: To Save the World, Save the Whales

As the world ponders ways to capture carbon and combat climate change, think about the idea of whales and carbon storage. During their long lifetimes, great whales takes gargantually more carbon dioxide out of the atmosphere than whole forests of trees – and keep it there. A new study underscores our cetacean cousins’ importance to our planet beyond just oceanic diversity. 

A sperm whale (Physeter macrocephalus) mother and her calf.

GREAT WHALES SWIMMING IN THE OCEANS DON’T SPRING TO MIND AS A SOLUTION TO GLOBAL WARMING. But a new analysis suggests that behemoths like blue and humpback whales can be amazing players in fighting climate change.

While planting trees to restore woodsy forests has  been an oft-mentioned idea for sequestering climate-warming carbon dioxide, “When it comes to saving the planet, one whale is worth 1,000 trees,” say a team of researchers in “Nature’s Solution to Climate Change,” published by the International Monetary Fund (IMF).

Additionally, they make a strong argument that the great whales (essentially, an average of large baleen and toothed whales) are as valuable to the world in economic terms as in traditional biodiversity concerns. International efforts to restore whale populations would be a low-tech, effective and economic solution with a successful funding model already in place, say the authors, IMF and university economists.


It’s been realized for some time that whales accumulate carbon in their bodies as they work to satisfy their voracious appetites. They capture carbon and store it efficiently in their blubber, where, largely, it stays. And they do so for a long time. According to whalefacts.org, giant cetaceans like blue whales may live as long as 90 years, humpbacks and fins as long as 100.

Estimates of whale carbon capture vary. The IMF researchers place it, on average, at 33 tons of CO2 for each whale over its lifetime. This compares to 48 pounds a year for a tree, they say.


An important fact about whales and carbon storage is that their role doesn’t end when their lives end. When a whale dies a natural death, it sinks to the ocean floor, a phenomenon called a “whale fall.”  There, its carcass is consumed by a broad spectrum of bottom-dwelling fishes, crabs, worms and bacteria. Its sequestered carbon stays there for centuries, the IMF researchers say, even thousands of years, other sources suggest.

great whales and carbon - whale fall remains
Skeletal remains – and ocean-bottom scavengers – from a whale fall off the California coast.

This is different from having whales killed and removed from the ocean by whalers. By drastically reducing whale populations, a researcher at the University of Maine has calculated, some 110 million tons of carbon have been released into the atmosphere over the past century.


And then, there’s the phytoplankton factor. Phytoplankton are  microscopic photosynthetic plants like diatoms, green algae and cocolithophores that sequester enormous amounts of carbon dioxide. Too small to be seen by the naked eye, they’re a huge part of the ever-present planktonic soup that becomes noticeable during large-scale algae blooms.

Through photosynthesis, phytoplankton convert the carbon in CO2 into the simple sugar nutrients they need to survive. As a happy side effect, they release the oxygen in CO2, adding an enormous amount of O2 to the atmosphere. The IMF folks calculate that they capture an estimated 40 percent of all carbon dioxide and release 50 percent of all the oxygen in the atmosphere.


Whales come into the picture here because they foster phytoplankton population growth. To put it bluntly, big whales poop in the ocean a lot and the stuff they dispense is rich in iron and nitrogen micronutrients, important to the growth of phytoplankton.

It’s a cycle. Shrimp-like krills eat the phytoplankton, baleen whales sweep up the krill, the whales produce their poop and the phytoplankton thrive.

”Whales have a multiplier effect of increasing phytoplankton production wherever they go,” the IMF team says. They calculate that “this is equivalent to the amount of CO2 captured by 1.70 trillion trees – four Amazon forests’ worth – or 70 times the amount absorbed by all the trees in the US Redwood National and State Parks each year. More phytoplankton means more carbon capture.”

great whales and carbon - whale poop video
A blue whale (Balaenoptera musculus) near Australia was captured by a drone in the act of producing a large – and highly visible – trail of phytoplankton-nutritious whale poop. Click on the image to view the video.


There’s no question, of course, that whale populations have suffered grievously from commercial whaling. In contrast to the world’s estimated pre-whaling population of four to five million great whales, today’s population is believed to be around 1.3 million.

Conservationists estimate that blue whales have been reduced to only 10 percent of their pre-whaling populations and sperm whales to about 30 percent. Species like minke whales have largely recovered but species like the North Atlantic right whale and the Antarctic blue whale are in threat of extinction.

Contrary to Moby Dick-influenced conceptions of 19th Century whalers chasing down their prey in sail-powered ships and oar-powered whale boats, it’s believed that during the 18th and 19th Centuries those whalers took at most some 300,000 sperm whales.


The advent of diesel engines, exploding harpoons and factory-like whaling fleets beginning around 1900 resulted in nearly three million whales being taken during the 20th Century. Early on, carbon-dense whale oil was sought for burning in oil lamps and the manufacture of soaps. In the 20th Century it was used as a machine lubricant and a constituent of automatic transmission fluids. For a while it was used to make margarine.


Considering the huge benefits surrounding whales and carbon storage, the IMF authors suggest that restoration of whale populations to their pre-whaling numbers of four to five million would add immensely to phytoplankton carbon capture. Even a one percent increase, they note, could capture hundreds of millions of tons of carbon dioxide a year, equivalent to two billion trees.

great whales and carbon - humpback whale
Humpback whale (Megaptera novaeangliae).


Since getting the world to do this is challenging, the IMF economists took a 21st Century approach – they put it in economic terms.

Adding worldwide whale tourism to the value of whales’ direct carbon capture and nutrient-dispensing activities, the IMF economists concluded that the public good of an individual great whale is worth some $2 million. The planet’s current cetacean population worth a more than $1 trillion.

That could increase if an IMF proposal to tax carbon were implemented. In that case, an individual great whale’s value could rise to more than $5 million.


Even though commercial whale hunting has largely ended, whales still face significant dangers from ship strikes, shipping and naval technology noises, fishing gear entanglement, plastic waste and other ocean pollutants and, of course, climate change.

And yeah, the authors note, “Protecting whales has a cost. Mitigating the many threats to whales involves compensating those causing the threats, a group that includes countries, businesses, and individuals. Ensuring that this approach is practical involves determining whales’ monetary value.”  And, whales’ climate benefits are spread all over the planet.


But how to reduce these myriad threats? “Luckily,” the IMF economists say, “economists know how these types of problems can be solved. In fact, a potential model for such solutions is the United Nations (UN) REDD [Reducing Emissions from Deforestation and Forest Degradation] program. Recognizing that deforestation accounts for 17 percent of carbon emissions, REDD provides incentives for countries to preserve their forests as a means of keeping COout of the atmosphere.

“In a similar way,” they suggest, we can create financial mechanisms to promote the restoration of the world’s whale populations. Incentives in the form of subsidies or other compensation could help those who incur significant costs as a result of whale protection. For example, shipping companies could be compensated for the cost of altered shipping routes to reduce the risk of collisions.”

great whales and carbon - bowhead whale mother and calf
Bowhead (Balaena mysticetus) mother and calf. Adult length: Up to 60 feet.


At their pre-whaling numbers, restored whale populations could capture some 1.7 billion tons of CO2 annually, the IMF economists write. “It would be worth about $13 per person a year to subsidize these whales’ CO2 sequestration efforts,” they say.

That leaves a myriad of questions. “If we agree to pay this cost, how should it be allocated across countries, individuals, and businesses?” they ask. And, “How much should each individual, company, and country that must bear some of the cost of protecting whales be compensated? And who will oversee the compensation, and monitor compliance with the new rules?”

“Coordinating the economics of whale protection must rise to the top of the global community’s climate agenda…. With the consequences of climate change here and now, there is no time to lose in identifying and implementing new methods to prevent or reverse harm to the global ecosystem.”

PRINCIPAL SOURCES: “Nature’s Solution to Climate Change,” International Monetary FundThe Whale Pump: Marine Mammals Enhance Primary Productivity in a Coastal Basin, PlosOne; The Impact of Whaling on the Ocean Carbon Cycle: Why Bigger Was Better, PlosOne; Whales, Whales Keep Carbon out of the Atmosphere, Scientific American;  Living whales are worth an enormous amount of money, Washington PostWhales, Wildlife Conservation SocietyA Whale of a Carbon Sink, Smithsonian; Whales and Climate Change: Our Gentle Giants Are Natural CO2 Regulators, h20.comBlue whale, world’s largest animal, caught on camera having a poo, Australian Broadcasting CompanyWorld’s whaling slaughter tallied, Nature;  How Long Do Whales Live, Whale Facts.; Whale Oil, et.al., Wikipedia.com.