Whales store a relatively large amount of carbon.

Alive and dead they are soaking up and storing the element, which has led a team of marine scientists to argue that conserving whales could help offset the negative effects of climate change.

Their findings are presented in a new scientific paper, “Whales in the carbon cycle: Can recovery remove carbon dioxide?” — co-authored by researchers from 10 academic institutions, including Craig R. Smith, from the Department of Oceanography at the University of Hawaii Manoa. As climate change accelerates, there is increasing value in the ability of whales to trap carbon, the research suggests. 

Whales are made up of around 20%-25% carbon. 

That’s of interest because as of now, the planet’s carbon levels, which influence Earth’s habitability, are much higher than the recommended 350 parts per million and rising, according to NASA.

Heidi Pearson, a marine biology professor at the University of Alaska Southeast and lead author of the paper, said whales’ roles in the ecosystem and their effects on the carbon cycle are not widely recognized. 

“We really don’t see any downside to whale conservation,” Pearson said. “It’s what we call a low-risk, low-regret solution. So there’s really no risk in whale conservation, other than, potentially redirecting funds from other sources.”

Martin van Aswegen, a doctoral student with the UH Manoa Institute of Marine Biology who was not involved in the paper, said its findings are important because “large whales can be the ‘canaries in the coal mine,’ providing valuable insights into the health of ecosystems around the world.”

Research has not yet determined if and how whale carbon should be used in climate-change mitigation strategies. However if whaling was made illegal worldwide, the researchers said, the subsequent legal protection would not only benefit whale populations but also the global environment when combined with other responses to climate change. 

Restoring whale populations, for example, could enhance carbon storage in whale biomass and sequestration in the deep sea when whales die and sink, a process called whale fall.

The carbon that they have stored will be out of contact with the atmosphere for about 1,000 years or more. As the carcass of the whale subsequently decomposes, the carbon may also begin to mix with sea sediments, removing the carbon from the atmosphere for millions of years.

Because climate change is already underway, van Aswegen said, it is not too late to take action. Industrial whaling nearly wiped out several whale species, he said, and the recovering species are having an increasingly difficult time due to the rapidly changing environment. 

Whales Add Economic Benefit

The research is relevant locally because Hawaii is an important breeding ground for humpback whales from December through the end of April each year, said Adam Pack, a biology professor at UH Hilo. “More than 10,000 humpbacks of all age classes, both sexes and females in different reproductive conditions migrate to Hawaii’s waters annually to mate and calve.”

“Whale falls due to natural morality, whale urine and excrement, whale placentas and whale sloughed skin all contribute to productivity, carbon export and carbon sequestration,” Pack said.

In addition to the many benefits of whales’ carbon storage abilities, researchers are also looking at the impacts the animals have economically.

Juan Carlos Villasenor-Derbez, a postdoctoral scholar at Stanford University, focuses his research on the economic value of whales and on quantifying the role that whales play in the global carbon cycle. He said that threatening whale populations also equates to lost revenue.

“Hopefully, within the next year or so, we’ll have the final result where we can say, every time you kill a whale, or a whale dies because of human actions, we are forgoing X dollars in carbon benefits,” Villasenor-Derbez said. “There might be tourism benefits. There might be cultural benefits. We’re not able to calculate those. We’re just focusing on the carbon side.” 

The International Monetary Fund already has established an economic value for an average great whale, by determining the value of the carbon it sequesters in its lifetime, the market price of carbon dioxide and other economic factors.

“Our conservative estimates put the value of the average great whale, based on its various activities,” the fund reports, “at more than $2 million, and easily over $1 trillion for the current stock of great whales.”