For more than 2 million years, the native forests on the South Pacific islands of Guam and Rota were home to several thousand crows, members of a species found nowhere else on Earth. But over the last 60 years, the Mariana crow—called the Aga in the Chamorro language—has completely disappeared from the island of Guam and rapidly declined on neighboring Rota. Today there are only about 175 Aga left on the planet.