Tonight’s bedtime stories included Bruce McMillan‘s Going On a Whale Watch, which led to opening the laptop to find pictures of blue whales in comparison to other living things, which led to searches on what they ate (I was pretty sure the largest animal ever on Earth ate tiny krill, and was right) but because the internet is awesome like that, it ended with an amazing discovery:
Blue whales make huge, red, floating poop.
Whale feces, it turns out, plays a substantial role in ocean ecosystems. Since it floats to the surface, it brings nitrogen whales have taken in when they fed in the ocean’s depths to shallow waters, providing a much-needed nutrient for plankton there. The massive mammals’ poop also serves as a significant carbon sink; one study estimated that excrement from sperm whales in the Southern Ocean alone sequestered 400,000 tons of carbon dioxide a year.