Figure 18. Relationship between loadings (Isotope Values and Morphological Measurements) of HY Pacific-slope flycatchers……………………... North American Birds, 2016), but, the International Union for Conservation of Nature (IUCN) lists 96 avian species as threatened (IUCN, 2016b) and the 2016 State of the Birds Report stated that 432 North American bird species, more than one-third of all bird species, are in need of immediate conservation action (North American Bird Conservation Initiative, 2016). As of June, 2016, the IUCN Red List stated that 140 avian species were extinct, five were extinct in the wild, 218 were critically endangered, 416 endangered, 741 were vulnerable, and 971 avian species were near threatened worldwide (IUCN, 2016a). Efforts in the U.S. to protect birds are varied and have deep roots. The first U.S. federal law protecting birds was the Lacey Act of 1900, which prohibited trading illegally obtained wildlife, prevented poaching and shipment of wildlife, and instituted later formed wildlife refuges (American Ornithologists' Union and Cooper Ornithological Society, 2016). In 1913, the Weeks-Mclean Act established federal protection for migratory waterfowl. Following the signing of the Migratory Bird Convention by Great Britain and the U.S. in 1916, a treaty that obliges both countries to protect and preserve migratory birds, the U.S. passed the Migratory Bird Treaty Act in 1918 (U.S. Fish & Wildlife Service, 2016b). The Migratory Bird Treaty Act continued to separate game birds from non-game birds through additional species classifications, and established a migratory bird list. Under the Migratory Bird Treaty Act, the pursuit, hunting, capturing, taking, killing, or selling of birds within the migratory bird list was prohibited (American Ornithologists' Union and Cooper Ornithological Society, 2016). Non-governmental efforts to protect birds have served important roles in supporting protective legislation with notable foundations of organizations such as The American Ornithologists' Union in 1883 (American Ornithologists' Union and Cooper Ornithological Society, 2016) and the Audubon Society in 1905 (Graham, 1990). Such organizations have laid the foundation for country wide efforts by non-profit organizations and researchers to protect birds. Some large-scale present-day efforts include those made by scientists, conservationists, anthropologists and educators involved with National Audubon Society, the Cornell Lab of Ornithology, the American Bird Conservancy, Partners in Flight, the Nature Conservancy, and many more. In the San Francisco Bay Area, non-profit organizations such as the San Francisco Bay Bird Observatory, Point Blue and the Golden Gate Raptor Observatory actively share missions to conserve and protect birds through scientific research, educational outreach, and management recommendations. In addition to, and often in collaboration with non-profit organizations, a large prevalence of academic researchers undertake efforts to protect birds. Many universities, locally and regionally s...