California Ricelands and Waterbird Habitat
- Part I:
Overview of Ricelands and Waterbird Habitat - Part II:
Overview of Waterbird Ecology and Conservation
Goals/Needs - Part III:
Sacramento Valley Species Snapshot - Part IV:
Riceland Shorebirds - Part V:
Riceland Wading Birds - Part VI:
Riceland Marsh Birds - Part VII:
Riceland Waterfowl - Part VIII:
Cooperative Partnerships to Enhance Ricelands Habitats - Part IX:
Riceland Waterbirds Future Vision - Part X:
Technical References
Part III: Sacramento Valley Waterbird Species Snapshot
Caterbirds are often described in terms of groups of birds that have similar characteristics or similar habitat needs. The main groups of waterbirds include shorebirds (plovers, stilts and avocets, sandpipers), wading birds (ibis, herons, egrets), secretive marsh birds (bitterns, rails, coots), and waterfowl (ducks, geese, swans). In the Sacramento Valley, there are species in each group that highly benefit from rice.
Waterbirds require many types of wetland habitat. Rivers, marshes, managed wetlands, flooded crop fields, and water delivery canals are all examples of habitat used by waterbirds. No one habitat is adequate to meet the needs of any single waterbird, and habitat use often overlaps between species. For example, Herons and egrets nest in trees along rivers, creeks, oxbow lakes, and in woodlots or even residential areas, but use flooded rice fields and wetlands for foraging. Stilts and avocets use rice fields to nest and forage in as well as a variety of other habitats. Each species nests in one habitat type that is used by another species for a different reason. In general, one habitat type would not be sufficient to provide nesting, foraging, and roosting habitat to either species. It is the interconnectedness of wetland habitats and rice fields that create a landscape suitable for all waterbirds in the Sacramento Valley.
The combination of wetland and flooded crop types helps to provide habitat for waterbirds year round. Managed wetlands are flooded seasonally, typically from fall through spring. Post-harvest winter-flooded rice supplements the available habitat during this time, but growing rice also supplies needed habitat in summer when managed wetlands are largely dry. Furthermore, with less than 60,000 acres presently existent (a fraction of historic natural wetlands), managed wetlands alone could not provide adequate habitat for the diversity of waterbirds in the Sacramento Valley. Flooded rice provides almost 500,000 acres of additional flooded habitat in summer and nearly 350,000 acres in winter.
Because waterbirds are reliant on water, the amount of available habitat on the landscape and the proximity to other habitats determines how many waterbirds are present. All else being equal, large tracts of wetlands support more waterbirds than small tracts of wetlands. Generally, areas with multiple types of habitat will have a greater number of species than areas with only one type of habitat.
The Sacramento Valley is a mosaic of rice fields, wetlands, and rivers and canals, each of which plays an integral part in providing habit to waterbirds.