Bison eradication stripped western grasslands of nutrients, Yellowstone research shows

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The remarkable seasonal flow of thousands of bison into and out of Yellowstone National Park is both a relic of an earlier, pre-settlement era and a source of great debate — Montana’s even sued in pursuit of fewer bison.

But there’s now less debate about the ecological good the herds of native herbivores bring to the landscape. A new study published in the journal Science shows that the migratory herds of bison effectively function as nature’s fertilizers, providing an astonishing 2.5-fold bump in crude proteins growing into the grasslands that blanket Yellowstone’s Northern Range.

“It’s mainly coming from urine and feces,” said Jerod Merkle, a professor of migr