Migration and Corridors

USGS scientists and partners are studying how growing goose populations in the California Central Valley wintering areas are affecting ducks and other waterfowl.

Considerable scientific research has been conducted in North America on nearly all aspects of the annual cycle of mallards, primarily focused on the breeding season. However, the period between when juveniles are capable of flight to their first southward migration remains a vastly understudied time for all waterfowl species. Beginning in 2018, a graduate student from South Dakota State University...

Collisons between wildlife and vehicles threaten many species, and can lead to human loss of life, injuries, and loss of property. USGS is developing models to help evaluate the effectiveness of wildlife protection zones and optimize the design of these protected areas.

Northern Prairie Wildlife Research Center (NPWRC) leads a collaborative effort, spanning several studies, with the objective of improving techniques to assess the quality of spring migration habitat for ducks. Spring is a critical time in in the life cycle of migratory ducks because during migration they experience peak energetic needs at a time when food resources are often at their scarcest...

The only self-sustaining population of endangered whooping cranes nests within and near Wood Buffalo National Park, Canada, migrates through the Great Plains, and winters primarily along the Texas Gulf Coast. Our objectives of this collaborative project are to address the entire annual life cycle of this species by advancing knowledge of breeding, wintering, and migration ecology, including...

Midcontinent sandhill cranes occupy a large geographic area of central and western North America and northeastern Asia during breeding, winter, and migration. They are a species representing a unique convergence of multiple user groups with an interest in the continued health of this population. Tens of thousands of people view cranes during spring staging at the Platte River Valley in Nebraska...

The USGS conducts research on marine wildlife, habitats, and processes to provide science to inform our partners as they make decisions relative to species status, resource use, and human activities.

Common loons often migrate several hundred miles to reach coastal waters during fall migration. Information about this part of the loon's life history is not well known. The use of satellite telemetry allows biologists to track loon movements through distant migrations and during winter. A transmitter attached to a radiomarked loon periodically sends a signal which is detected by a satellite-based...

The presence of top predators is considered an indication of ecosystem health and can play a vital role in ecosystem functioning by promoting biodiversity, and can contribute to regulating prey species abundance, and herbivory. In the intermountain west, the largest mammalian predator and obligate carnivore is the mountain lion, Puma concolor. This elusive and wide-ranging predator occupies a...

The Suisun Marsh and Central Valley in California offer some of the world’s most important wetland habitats for waterfowl in the Pacific Flyway. Mike Casazza and USGS WERC biologists are providing the science to support and evaluate waterfowl populations and habitat management in North America.

Years after the last inmate departed Alcatraz Island, waterbirds like Black-crowned Night Herons and Snowy Egrets still make the forbidding island their home. The National Park Service has requested the aid of WERC’s Dr. Pete Coates to inform efforts to expand visitor access to the Island, and simultaneously maintain healthy waterbird populations.

The Challenge Over the last two decades, the Eastern migratory population of monarch butterflies has declined by about 80%, leading many scientists to consider how to best conserve and rebuild monarch populations. Conservation efforts can be challenging to design and execute because of the multi-generational migration of monarchs that spans North America. Conservationists must consider many...