California’s interior is home to a suite of waterbird species that rely upon freshwater lakes and marshes in the state’s interior for their breeding cycle. In fact, they breed in sizable concentrations, in colonies, where habitat is available. White Pelicans, California Gulls, Black Terns, and Double-crested Cormorants are among the seven species that fly to ancestral sites such as the Klamath Basin to build their nests and raise their young. Today, the changing water regime statewide makes flooded agricultural fields potential nest habitat for some of these waterbirds.

The waterscape in our region has changed drastically in the past 200 years. Before settlement by Euro-Americans, California’s interior was laced with wetlands and lakes, even in summer, and they teemed with breeding birds. Today, by contrast, natural marshlands are rare and ephemeral. Private lands now hold some of the greatest wetland habitat and potential for more. As demand for limited water supplies intensify, and our climate changes, some populations of inland breeding waterbirds may be pushed to the limit. Until recently, however, their status was essentially unknown.

To fill this gap in knowledge, since 1997 Point Blue has surveyed all of the state’s remote regions, documenting the colony size, distribution, and habitat requirements of all seven species of colonial waterbirds that breed in the region. Point Blue ecologists, especially Senior Biologist Dave Shuford, conducted this field work and also examined ways that yearly rainfall – highly variable – affects the birds and their habitats. Our reports to the State of California represent the most complete and up-to-date information available in considering water allocations.

Also shown in our findings: California’s inland-breeding seabirds are resilient: some can shift to flooded rice fields or otherwise make use of nest habitat shaped by agriculture; many can take advantage of the sudden appearance or reappearance of habitat when rainfall is superabundant. Their resilience and our information may support the continued presence of these majestic species in California. 

Learn more about one inland colonial waterbird, the Black Tern, in our special status species section.