17 states filed a lawsuit against the Trump Administration Wednesday in an effort to try and stop the rollback of the Endangered Species Act.

Why it matters: The landmark act from the Nixon administration helped save species including the bald eagle and grizzly bear from extinction, per the New York Times. The Trump administration claims the changes will help reduce regulatory burden on the Interior Department. The new rules were to take effect Thursday, AP notes.

Go deeper: 3 billion birds have been lost in U.S. and Canada since 1970