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What's the Big Deal about Bison?
The bison effect
Bison eat grasses -- lots and lots of grasses. As bison munch their way across grasslands, they create habitat for other animals. Birds nest where bison have grazed and hunt insects among the exposed grasses. Prairie dogs build colonies where bison have cut down grasses. Black-footed ferrets then come in search of the prairie dogs, their favorite prey.
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