This past spring a lonely plover stopped by a beach along the St. Louis River, which winds southwest out of Lake Superior. A century ago, this wouldn't have been an unusual sight; some 800 pairs of Piping Plovers nested around the Great Lakes system then, before habitat loss and predation caused a spiraling decline to less than 20 pairs by 1986. Subsequent recovery efforts—managing and cleaning up habitat, banding birds, and even starting a captive breeding program—invited some of the beloved birds back to the Great Lakes to nest. But even after 31 years of restoration, no plovers returned to the spot along the St. Louis River. So the plover visitor that day was a novelty. Luckily, a bird monitor from the local nonprofit St. Louis River Alliance caught an exciting glimpse of the wader as it poked around the beach, foraging for food—but only for a fleeting moment. Before long, a dog scampered into view, spooking the shorebird and cutting its visit short. It didn’t...