Pacific Americas Flyway

Pacific Americas Flyway
Name	Pacific Americas Flyway
Region	Pacific Coast of the Americas
Countries	United States; Canada; Mexico; Guatemala; El Salvador; Honduras; Nicaragua; Costa Rica; Panama; Colombia; Ecuador; Peru; Chile
Birds	Shorebirds; Waterfowl; Raptors; Passerines
Length	~13,000 km

Pacific Americas Flyway The Pacific Americas Flyway is a principal avian migration corridor linking Alaska, British Columbia, Yukon, Washington (state), Oregon, California, Baja California, Sonora (state), Sinaloa, Nayarit, Jalisco, Colima, Michoacán, Guerrero, Oaxaca, Chiapas, Veracruz (state), Tabasco (state), Campeche, Yucatán, Quintana Roo, Belize, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru, and Chile. It functions as a transcontinental route for migratory birds between Arctic breeding grounds and Neotropical wintering areas, connecting landmarks such as Prudhoe Bay, Kodiak Island, Vancouver Island, Puget Sound, San Francisco Bay, Monterey Bay, Gulf of California, Baja California Peninsula, Gulf of Tehuantepec, Isthmus of Panama, Chocó (biogeographic region), Galápagos Islands, Andes Mountains, and Atacama Desert. The flyway supports species that travel along coastlines, wetlands, and interior corridors used by birds monitored by institutions including the U.S. Fish and Wildlife Service, Environment and Climate Change Canada, Servicio de Administración Tributaria (Mexico), The Nature Conservancy, and the BirdLife International partnership.

Overview and Extent

The flyway spans Arctic tundra such as North Slope Borough, Alaska, boreal forests like Yukon Flats National Wildlife Refuge, temperate zones including Pacific Northwest National Scenic Trail regions, Mediterranean-climate zones exemplified by Point Reyes National Seashore, subtropical coastal lagoons such as Bahía de San Quintín, tropical mangroves in Sian Ka'an Biosphere Reserve, and austral extents reaching Central Chile. Major geopolitical jurisdictions overlapping the route include the United States Department of the Interior, Environment and Climate Change Canada, and the Secretaría de Medio Ambiente y Recursos Naturales. Flyway length estimates and seasonal timing are compiled by research centers such as the U.S. Geological Survey, Smithsonian Institution, American Museum of Natural History, and university programs at University of Alaska Fairbanks, University of British Columbia, University of California, Davis, Universidad Nacional Autónoma de México, Universidad de Costa Rica, and Pontificia Universidad Católica de Chile.

Migratory Species and Biodiversity

A wide taxonomic range uses the corridor: shorebirds like the Western Sandpiper, Semipalmated Sandpiper, Red Knot, and Dunlin; waterfowl including Greater White-fronted Goose, Snow Goose, and Canada Goose; raptors such as Peregrine Falcon and Swainson's Hawk; and passerines like Blackpoll Warbler and Swainson's Thrush. Important families represented include Scolopacidae, Anatidae, Accipitridae, and Parulidae. The flyway also supports threatened taxa listed under instruments such as the U.S. Endangered Species Act and conventions like the Convention on International Trade in Endangered Species of Wild Fauna and Flora, which protect species including Aleutian Canada Goose, California Condor, and Red Knot (rufa) populations monitored by groups such as the National Audubon Society and Wetlands International. Biodiversity hotspots intersecting the route include the California Floristic Province, Mesoamerican Barrier Reef System, and Tumbes-Chocó-Magdalena.

Major Stopover Sites and Habitats

Key staging and refueling locations include Yukon-Kuskokwim Delta, Copper River Delta, Salt Pond Shorebird Reserve, Willapa Bay, Grays Harbor, San Francisco Bay National Wildlife Refuge Complex, Bolsa Chica Ecological Reserve, Elkhorn Slough, Mono Lake, Salton Sea, Bahía de San Quintín, Ojo de Liebre Lagoon, Bahía Magdalena, Estero de Urias, Mouth of the Colorado River, Gulf Coast of Oaxaca, Bahía de Jiquilisco, Bahía de Cárdenas, Gulf of Nicoya, Golfo de Chiriquí, Golfo de Guayaquil, and Río Biobío estuary. Habitat types include intertidal mudflats like Bolinas Lagoon, saltmarshes such as Elkhorn Slough National Estuarine Research Reserve, tidal marshes in San Pablo Bay, freshwater wetlands exemplified by Klamath Basin National Wildlife Refuges Complex, coastal lagoons like Laguna de Chacahua, mangrove stands in Sian Ka'an, and high-elevation stopovers in the Sierra Nevada (United States) and Andes. Management units include National Wildlife Refuge (United States), Ramsar sites, UNESCO Biosphere Reserves, and national parks like Channel Islands National Park and Tortuguero National Park.

Conservation Issues and Threats

Threats include habitat loss from urbanization in Los Angeles, San Diego County, California, Vancouver, Mexico City, and Santiago de Chile; wetland drainage for agriculture in Imperial Valley and Nayarit; pollution events such as oil spills exemplified by incidents off Santa Barbara Channel and near Guerrero; disturbance from tourism at Point Reyes and Monterey Bay; invasive species impacts in Galápagos Islands and Isla Espíritu Santo; and climate-driven changes affecting breeding grounds in Arctic National Wildlife Refuge, sea-level rise affecting San Francisco Bay, and altered wind regimes impacting stopover energetics studied near Cape Mendocino and Cabo San Lucas. Emerging concerns include disease outbreaks monitored by Centers for Disease Control and Prevention, pesticide exposure associated with practices in Central Valley (California), and cumulative impacts from energy development near Cook Inlet and Gulf of Tehuantepec.

Management, Monitoring, and International Agreements

Governance and coordination involve instruments and organizations such as the Migratory Bird Treaty Act of 1918, the North American Wetlands Conservation Act, the Ramsar Convention on Wetlands, the Western Hemisphere Shorebird Reserve Network, and the Convention for the Conservation of Migratory Species of Wild Animals. Agencies and NGOs participating include U.S. Fish and Wildlife Service, Environment and Climate Change Canada, Comisión Nacional para el Conocimiento y Uso de la Biodiversidad, Secretaría de Medio Ambiente y Recursos Naturales (SEMARNAT), Bird Conservancy of the Rockies, Manomet, Bird Studies Canada, Pronatura México, Conservación Internacional, Sociedad Peruana de Derecho Ambiental, and Comisión Nacional de Áreas Naturales Protegidas. Monitoring frameworks deploy techniques from banding programs run by U.S. Geological Survey Bird Banding Laboratory and Banding Office (Canada), satellite telemetry projects by Cornell Lab of Ornithology and University of Florida, and citizen science platforms including eBird and Christmas Bird Count coordinated by the National Audubon Society.

Research and Long-term Studies

Longitudinal studies examine population trends at sites like Mono Lake Committee monitoring, Klamath Basin surveys, and Yukon Delta National Wildlife Refuge counts. Research institutions active in the flyway include Scripps Institution of Oceanography, Hubbard Brook Experimental Forest, Point Blue Conservation Science, Canadian Wildlife Service, El Colegio de la Frontera Sur, Smithsonian Tropical Research Institute, and Universidad San Francisco de Quito. Key research topics encompass phenology shifts recorded by National Phenology Network, stopover ecology investigated using light-level geolocators by British Antarctic Survey collaborators, contaminant studies published in journals such as Science, Nature, and Ecology Letters, and conservation planning informed by modeling tools developed at University of Washington and Stanford University. Long-term datasets derived from programs like Monitoring Avian Productivity and Survivorship and multidisciplinary initiatives including Arctic Council assessments provide critical inputs for adaptive management.

Category:Bird migration