Burning, Flooding, and Wildlife

As a result of the California Rice Straw Burning Reduction Act of 1992, many farm owners and managers have turned to winter flooding of rice fields to assist in decomposition of waste rice straw. This winter flooding to decompose rice straw also has proven an invaluable source of winter habitat for millions of migratory birds and other wetland-dependent species. Forty-six species of waterbird have been recorded on flooded rice fields in the Central Valley in winter. In fact, a recent study comparing waterbird use of natural wetlands and flooded rice fields demonstrated that in many respects, these two habitat types are functionally equivalent. However, most of these same birds used unflooded rice fields only sparingly.

Most people know that rice has been important as food for people for thousands of years. However, perhaps fewer people are aware of the positive wildlife benefits associated with rice agriculture.

For animals that depend on relatively open-water wetland habitats, rice fields often prove to be welcomed sites on an otherwise inhospitable landscape. This is particularly true for many species of migratory birds. Ducks, geese, shorebirds (e.g. sandpipers, plovers), and wading birds (e.g. herons, egrets) in North America have been especially hard hit by loss of wetland habitats (up to 90% loss in some states!).

Flooded rice fields, while certainly not perfect proxies for natural wetlands, can provide many of the essential needs for these birds – and often in just the right place at just the right time!

Wetland birds use rice fields extensively in each of the major rice growing regions of the U.S. - Lower Mississippi River Valley, Gulf Coastal Plain, and Central Valley of California. Because of differences in rice culture practices, bird species present, and geographic location among these regions, the major issues and management practices also differ. Read below to find out more.

Gulf Coastal Plain

Because of its historically abundant coastal and prairie marshes and its geographic position in the Central and Mississippi Flyways, the Gulf Coastal Plains region is one of the most important to migratory birds on the continent. However, loss of shallow coastal wetlands threatens the viability of many bird populations. Flooded rice fields provide excellent feeding and resting habitat for migrating and wintering ducks, geese, and shorebirds in this important region.

Over 50% of the rice acreage in the U.S. can be found in the Lower Mississippi Alluvial valley. This region annually hosts tens of millions of ducks, geese, wading birds and shorebirds. Loss of the natural wetlands that many of these need has been well documented. Fortunately, winter flooding of rice fields by farmers in the Lower Mississippi Valley is providing valuable wildlife habitat and helping to maintain cleaner water in the region’s streams.

California’s Central Valley is one of North America’s most important regions for wintering and migrating waterfowl. Historically, nearly 40 million ducks and geese fed and rested in its extensive shallow wetlands. Unfortunately, only 5% of these wetlands remain, forcing wetland-dependent birds into fewer, crowded habitats. Rice agriculture in the Central Valley holds the key to providing much of the waterfowl habitat objectives set by the North American Waterfowl Management Plan. In addition, these habitats are used extensively by dozens of other bird species, including shorebirds, egrets, and herons.

Ducks Unlimited, in cooperation with federal and state agencies and the rice industry, helps provide funds and monitoring of the continued winter flooding of rice fields through the Valley/Bay CARE initiative. Valley/Bay CARE began in 1992 with the cooperative efforts of DU, the California Wildlife Conservation Board, the J. M. Long Foundation, regional resource conservation districts, county farm bureaus, and cooperating rice growers. Beginning with 50 growers and 7,000 acres of flooded rice, the program has grown to 200 growers flooding nearly 140,000 acres of rice. Growers typically flood harvested fields, then roll and crush the straw to enhance decomposition.