Stretching from the Arctic regions of northeastern Russia, Alaska, and western Canada and along the Pacific coastlines of North, Central, and South America, the Pacific Flyway traverses some of our planet's greatest climatic and topographic extremes. Defined by water, the flyway encompasses a sweeping expanse of coastal and offshore marine ecosystems and an inland archipelago of freshwater wetlands. Hemispheric in scope, this integrated network of ecosystems is linked by its moving parts—the millions of migratory birds whose lives depend on this 10,000-mile (16,000-km) corridor as they travel between their breeding and overwintering grounds. With their ocean- and continent-spanning travels, waterbirds are our sentinels in a changing world—each of their journeys revealing the fraying edges of the web of life that sustains us all. perfectly blends amazing photography, science writing, and storytelling to illuminate the profound challenges faced by migratory birds and to inspire a longterm commitment to global conservation efforts.