Whales are actually cash cows, or so suggest economists with the International Monetary Fund. A team helmed by Ralph Chami took a look at the economic benefit provided by whales when it comes to carbon sequestration and ecotourism and arrived at a big figure: $2 million apiece. Their analysis hasn't yet appeared in a peer-reviewed journal, and some hypotheticals were used to arrive at that number, but Chami's goal is to "start a conversation with the policymakers who don't buy into saving animals for the sake of animals." National Geographic unpacks the science, noting that great whales' carbon-capture abilities take shape in two forms: First, they store carbon dioxide in their bodies, "stockpiling tons of carbon apiece like giant, swimming trees."
Upon their death, it doesn't escape, but rather sinks to the ocean floor, preventing it from reentering the atmospheric cycle for hundreds of years at a minimum. In an online paper, the economists write that a single great whale carcass can bring 33 tons of CO2 to the ocean floor; by comparison, a tree pulls 48 pounds of CO2 from the atmosphere each year, making one dead whale the equivalent of 1,375 trees. Second, whales also release nutrients like nitrogen and iron via their urine and excrement. That boosts the growth of phytoplankton, which draw carbon from their air and can also sink to the bottom of the sea after dying. Do some math using the current market price of carbon dioxide, tack on ecotourism, and the team arrived at their $2 million figure—"and easily over $1 trillion for the current stock of great whales," they write. (Read more discoveries stories.)