The Birdwing Pearlymussel's endangered numbers flourish in the Duck River, the most biologically diverse river in North America.

Its historic range has declined by over 90% due to dams, water impoundments, coal mining pollution, and historical sedimentation.

It is a reminder that even the smallest, sometimes hidden creatures have an essential part to play.

Above: The Greenside darter acts as an essential host fish for the reproduction of the birdwing pearlymussel. By: Dr. Amanda Rosenberger, a mussel expert and research ecologist.

Learn more: The Nature Conservancy