A peregrine falcon surveys the concrete canyons of Chicago

A peregrine falcon surveys the concrete canyons of Chicago

We chose this peregrine falcon photo—a female, walking across the rail of a balcony in Chicago—to inspire hope on Endangered Species Day. Not every animal listed as endangered is doomed to extinction. Peregrine populations were decimated by pesticide use, such as DDT, in the mid-20th century. The chemicals accumulated in the birds’ bodies, causing weak egg shells and high mortality rates for chicks. But by the 1980s humans had learned the cause, reduced and eliminated the various chemicals, and helped the birds rebound with gusto .