WHO: Two pairs of whooping cranes, one of the world’s most endangered birds. WHAT: The animals are laying eggs in Texas—on private land in Jefferson and Chambers counties, east of Houston—for the first time since the late 1800s. WHY IT’S SO GREAT: Every fall, the world’s last self-sustaining migratory flock of wild whooping cranes descends on the marshes of the Aransas National Wildlife Refuge. One of only two crane species native to North America, the whooping crane is the continent’s tallest and rarest bird: five feet high with crisp white feathers, a red-capped head, and a ratcheting, mournful call. The wild flock’s 506 birds spend the winter in the 115,000-acre refuge, fattening up on blue crabs, clams, and fish, before traveling back to northern Canada to breed.