New research shows that the diarrhea-like waste from whales is rich in iron so it stimulates the growth of phytoplankton, which then serve as carbon traps that remove some 400,000 estimated tons of carbon from the atmosphere each year.
This photograph shows an Antarctic minke whale in the Southern Ocean. The giant gas bubble emanating from the whale suggests that flatulence is just as common for ocean mammals as it is for humans and many other terrestrial animals.
Antarctic Division marine biologist Nick Gales scoops whale poo from water. When whales consume iron-rich krill, they excrete most of the iron back into the water.
That triggers the growth of phytoplankton. The phytoplankton take up carbon from the ocean as they grow. Through the entire life and death cycle of these plants, the carbon then stays trapped for centuries.
A scientist collects a fecal whale sample from a net. Most whale waste is not solid, but comes out as a giant liquid plume (save for the undigested squid beaks).
Other marine mammals probably beneficially redistribute carbon just as whales do. These may include seals, sea lions and sea otters.
Blue and Red
Blue whale poop is shown. The red coloration is a result of the whale's krill diet.
"It is sometimes thought that conservationists try to 'save the whales' only because they are cute," says Trisha Lavery a marine biologist at Flinders University of South Australia. But, as she points out, the animals (and their waste) "play a crucial role in marine ecosystems."