Top, Bald Eagle; middle, Peregrine Falcon; bottom, Whooping Crane (Courtesy NEBRASKAland Magazine/NGPC)

Birds are a vital - and highly visible - part of life on our planet. Maybe you've heard the expression, "A little bird told me." Birds really do tell us things.

They often serve as biological indicators-- they help us measure the health of the environment we share.

For example, people learned about the dangers of certain chemicals from Bald Eagles. By studying the eagles, along with other raptors at the top of the food chain, we learned these birds were having difficulties reproducing due to the effects of pesticide residues in their food. That knowledge led to changes in the way we make and use pesticides.

Birds can also serve as symbols. Mention the Whooping Crane and people think of endangered species. We associate the Whooping Crane with elusiveness and fragility for good reason. The Whooping Crane requires remote, undisturbed wetland habitats in which to raise its young. How remote? The exact location of the Whooping Cranes nesting area in Canada was not discovered by scientists until 1952. Now that's an elusive bird.

Other bird species offer us tremendous displays of adaptability and resilience, like the Peregrine Falcon. This bird not only made it back from the edge of extinction, it has learned it can live without the cliffs it once called home. Many Peregrine Falcons nest and raise their young atop the tall urban buildings so graciously provided by human beings. Like the people in the offices and apartments below them, they're content with this type of high-rise living.

In addition to all they show us and tell us, healthy populations of birds enhance the quality of our outdoor experiences and enrich our overall quality of life.