With their massive bodies and giant plumes of poop, great whales can move a whole lot of organic material around our planet. Depending on the animal’s numbers, this might make them a valuable carbon sink, researchers propose.University of Alaska Southeast marine biologist Heidi Pearson and colleagues review the scientific literature in a new paper, to assess just how much of an impact these giant mammals might have as a natural climate solution.”Blue (Balaenoptera musculus) and fin (Balaenoptera physalus) whales are the two largest animals to ever exist on Earth,” Pearson and team explain in their review. “Their size and longevity allow great whales to exert strong effects on the carbon cycle by storing carbon more effectively than small animals, ingesting extreme quantities of prey, and producing large volumes of waste products.”Great whales, which include the filter feeding baleen whales and toothed sperm whales, play a significant role in the ocean’s biological carbon pump, cycling the carbon between the ocean and atmosphere.
Some of these marine mammals can live up to 200 years. Given artificial attempts at using the ocean depths to sequester carbon ‘leak’ around 75 percent of their stock in half that time, that’s a decent period for locking up whale-sized chunks of carbon.They eat around four percent of their weight in krill and plankton each day, which adds up to around 8,000 pounds for blue whales. Their resulting poop tsunamis then feed CO2-sequestering plankton that float near the ocean’s surface with otherwise out-of-reach nutrients like iron and nitrogen. Krill feed on those plankton, passing on those nutrients and carbon to the many animals that feast on them in turn, including penguins, birds, seals, fish and, of course, the whales. The whale carbon pump. (Alex Boersma/Pearson et al., Trends Ecol. Evol. 2022)In fact, previous studies have found that despite whales eating krill, higher concentra …