Whale feces probably don't cross your mind very often, but when they do, you likely cringe at the thought of their size, sight and smell. Blue whales, for example, grow to be longer than a school bus and rank as the largest animals known to live on Earth, so naturally, they're going to eat -- and poop -- a lot. A new study found that whale dumpings are highly valuable to marine ecosystems, and they're not something to write off as stinky or gross.
The new study, recently published in Marine Mammal Science, stresses that blue whale poop is essential to primary production in the Southern Ocean, and therefore benefits fisheries. Blue whale excrement is rich in iron -- a nutrient that's lacking in surface waters of the Southern Ocean. So, when blue whales defecate their iron-rich poo in surface waters, they play a key role in enhancing the food chain: Iron stimulates phytoplankton blooms, the main food source for krill, and these blooms then benefit blue whales, who eat up to four tons of krill a day.