Book excerpt: From majestic Bald Eagles to tiny Elf Owls, raptors are nature’s most fascinating and powerful birds. As predators with wide ranging habitats and food sources, raptors also serve as a litmus test for the health of their ecosystems. To preserve a species such as the Everglade Kite or Spotted Owl is to ensure the survival of many other creatures. Ornithologists Noel and Helen Snyder have spent nearly fifty years studying and photographing birds of prey in their natural habitat. The result of decades of firsthand field studies combined with key biological and conservation studies by other experts, Raptors of North America presents a comprehensive and captivating account of our continent’s birds of prey. Readers will meet the nocturnal raptors, the owls, and the diurnal raptors: hawks, harriers, kites, falcons, eagles, ospreys, vultures, and condors. This book was an editor's choice of the Scientific American Book Club.