By any measure, the revival of the bald eagle stands as one of the great environmental triumphs in conservation history. In 1963, the national bird teetered on the precipice of extinction, with only 417 known nesting pairs left in the lower 48 states.

Hammered by habitat loss and synthetic insecticides, the eagle, the abiding symbol of American strength and freedom, had all but vanished from our landscapes. From backyard birders to federal agencies, Americans responded with unity and urgency. The Environmental Protection Agency banned pesticide DDT in 1972. Congress passed the Endangered Species Act the next year, and launched aggressive habitat conservation programs nationwide.

Today, more than 300,000 bald eagles (and 71,400 breeding pairs) soar through America’s skies.

Now, another iconic species is disappearing before our eyes. If there is no bird more American than the eagle, there is no butterfly more American than the monarch. Breathtaking and resilient, the monarch butterfly completes one of the most astounding migrations in nature − a multigenerational pilgrimage spanning over 3,000 miles, from Canada to Mexico and back.

Along the way, it relies on a dwindling network of native plants, roosting trees and wildflower-rich terrain for survival.

In the past two decades, driven by habitat destruction, herbicide use and changing climate conditions, monarch populations have

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