I saw my first Cerulean Warbler in the realm of the dead. I was 12 when I visited Mount Auburn Cemetery, a rolling 175-acre burial space that straddles the border between Cambridge and Watertown, Massachusetts. The immense trees were bright with new spring growth; the gravestones and soaring obelisks were intimidating. This seemed like a serious place for serious people. Suddenly, two ecstatic birders flailed their arms in my direction. “Psst, come check this out,” they whispered. At the very top of an oak, a tiny sky-blue bird was bopping from twig to twig, chowing down on caterpillars. Boom. My lifer Cerulean Warbler. In an instant, my point of view on cemeteries expanded. We birders love to haunt unappreciated places. We know that some of the best birds hang out at dumps and sewage lagoons, and we’ve been skulking around headstones for decades, even centuries. Lucky for us, cemeteries have evolved from spook yards to bird-friendly havens, thanks to the efforts of a...