Are Elephants Aiding Us in Fighting Climate Change?

You probably don't picture a lush, prosperous forest full of tall trees when you hear the phrase, "It looks like a herd of elephants came through here." Because of their size and bulk, elephants are often mistaken for destroyers rather than protectors. However, some populations of elephants have adapted to living in forests, and not only do those forests typically survive, but those elephants and their finicky palates are doing the entire planet—not just the forest—a favor. Carbon sequestration is the cause. One of our most effective weapons in the fight against climate change is carbon sequestration, a term with several meanings. It frequently refers to equipment that purges carbon dioxide from the atmosphere. Though it is still in its early stages, engineers have been working to develop this technology.

Additionally, there is natural carbon sequestration. Ecosystems then utilize natural processes to remove carbon from the atmosphere. A large portion of the carbon in soil comes from decomposing plant matter, microorganisms, and other sources.

With all the trees growing and absorbing carbon dioxide into the wood and other plant matter, forests are also pretty good at storing carbon. Elephants might be thought of as partially reversing that process. What is the point of all the stomping, anyway? Despite being adapted to living in forests, forest elephants are not required by evolution to aid in the forest's ability to store carbon, but they do.

African forest elephants, distinct from the elephants you've probably seen thundering around the Savannah in National Geographic, were the focus of a study conducted by the National Academy of Sciences in the years before 2023. Savannah elephants consume a careless diet of grass, bark, leaves, fruit, foliage, or anything else they can find. However, most of what African forest elephants eat are leaves, and like people, they favor tasty leaves. They typically consume fewer fibrous leaves and are devoid of unpleasant chemicals like tannins than the leaves they avoid.

Because tannins are a defensive chemical, other animals don't appreciate them like some humans do because they make wine dry and noticeably bitter. Elephants stay away from them because they are smarter than you, so we're not supposed to like them. Elephants prefer leaves from trees with low wood density because they are more palatable. The ability of these trees to store carbon is subpar. Because the wood is less dense, there is less carbon on a volume basis. As a result, the elephants are uprooting, eating, and eventually thinning out the less effective trees at capturing carbon and leaving those that are. But there's more: fruit is also a favorite snack of forest elephants.

Elephants prefer fruit that grows on different trees with higher wood densities. When elephants consume fruit from these trees, they help spread the seeds of those trees, increasing the number of dense wood trees in the forest and increasing carbon sequestration. In a second sense, it's a delicate balance, and it's difficult to quantify how much climate change elephants might be able to halt simply by going about their daily lives. According to the authors, a forest without elephants may store up to 9% less carbon in its trees due to the effect on high wood-density trees alone.

Large herbivores other than elephants can also have an adverse effect on carbon stock levels. Although megaherbivores are less common than they once were, the presence of any kind of large wild herbivores appears to positively contribute to soil carbon, not just in forests but also in grasslands. There were at least 50 different species present during the late Pleistocene. While all those mega herbivores consumed a lot of plants, they also spread seeds, cycled nutrients, and made ecosystems less vulnerable to fire. It appears likely that they also helped store carbon in a manner similar to how elephants do today. Three species of elephants, hippos, rhinos, giraffes, and bovines like bison are among the remaining Mega herbivores. Although protecting them for carbon storage may seem selfish, I'll take any justification they give us to learn more about elephants.