"SAVE THE WHALES" has long been a slogan for conservationist's bumper stickers and fridge magnets. But in recent years, many have begun to ask why. Why is it important to spend resources trying to conserve large, charismatic megafauna like whales? Sure, they're beautiful, and smart, and yeah, I guess a world without whales is kinda sad, but shouldn't we have a more... practical reason?

New research by Joe Roman, from the University of Vermont, has provided just such a reason. He found that great whales directly and effectively maintain oceanic balance, and contribute to carbon storage (reducing global warming). For example, they shuttle nutrients throughout the water, acting as a pump that feeds at great depths and then releases "fecal plumes" near the surface. They move thousands of miles, from high latitudes to low, shuttling nutrients with them. Also, whales directly reduce the amount of carbon in the atmosphere: whale poop is a critical source of carbon storage! Even in death whales improve ocean ecosystems; their bodies sink to the bottom, providing habitat to many species (including some that live only on whale carcasses).

Every species has a role in maintaining healthy ecosystems, and for large, long-lived, influential species like whales, each surviving individual -- and each that dies-- counts for a lot. Further, if we focus conservation efforts on large, keystone species, many populations of smaller species are protected right along with the big. (If we set aside a big land reserve to protect wolves, everything else that lives there-- from bugs to birds to birches-- is protected too). And the more diverse an ecosystem is-- that is, the more species that persist-- the more stable it will be.

(Thanks to reddit use mubukugrappa for the link)