Nation’s grassland birds, found in 14 states, have declined 43% since 1970, more than any other category, and are currently ...

EDITOR’S NOTE: This story is a collaboration between The Associated Press and Grist.

The plains viscacha looks a lot like a chinchilla, but it's known for building vast tunnels underground and for producing ...

The endangered mammals are among the smallest of their kind in North America, according to the Bureau of Land Management.