Our Livin,^ Resources 



Contents 



Foreword v 



Preface vi 



In Menioriam vi 



Acknowledgments vii 



Part 1 Introduction 



Overview 3 



Biodiversity: A New Ciiailenge 6 



Conservation Landmarks: Bureau of Biological Survey and National Biological Service .... 7 

 Activities of the Bureau of Biological Survey 8 



Part 2 Distribution, Abundance, and Health 



Species ^^-^^^.^— — ^^^.^^^— — ^^^— — ^^^^^^^— — — ^— ^— — ^^^^^ 



Birds 



Overview 15 



Breeding Bird Survey: Population Trends 1966-92 17 



Winter Population Trends of Selected Songbirds 21 



Breeding Productivity and Adult Survival in Nongame Birds 23 



Canada Geese in North America 26 



Canada Geese in the Atlantic Flyway 28 



Arctic Nesting Geese: Alaskan Populations 30 



North American Ducks 34 



Decline of Northern Pintails 38 



Canvasback Ducks 40 



Breeding Seabirds in California, Oregon, and Washington 43 



Seabirds in Alaska 49 



Colonial Waterbirds 53 



Shorebirds: East of the 105th Meridian 57 



Western North American Shorebirds 60 



Raptors 65 



Causes of Eagle Deaths 68 



Return of Wild Turkeys 70 



Mourning Doves 71 



Common Ravens in the Southwestern United States, 1968-92 73 



Mississippi Sandhill Cranes 75 



Piping Plovers 77 



California Condors 80 



Audubon's Crested Caracara in Florida 82 



Puerto Rican Parrots 83 



Red-cockaded Woodpeckers 86 



Southwestern Willow Flycatchers in the Grand Canyon 89 



Mammals 



Overview 93 



Marine Mammals 94 



Indiana Bats 97 



Gray Wolves 98 



Black Bears in North America 100 



Giizzly Bears 103 



Black-footed Ferrets 106 



American Badgers in Illinois 108 



California Sea Otters 110 



White-tailed Deer in the Northeast 112 



Deer Management at Parks and Refuges 113 



North American Elk 115 



Reptiles and Amphibians 



Overview 117 



Turtles 118 



Marine Turtles in the Southeast 121 



