Helen Snyder and her husband Noel are the authors of Voyageur Pressu2019s Birds of Prey: Natural History and Conservation of North American Raptors (1991). They are best known for their efforts to preserve two endangered species - the Puerto Rican Parrot and the California Condor. Their contributions to zoological research and conservation have also involved many other species, including a fifty-year study of owls. The Snyders reside in Arizona.