Letting ducks forage on flooded rice fields is an effective way to break down rice straw, and a viable alternative to burning, according to a University of California, Davis study. "The ducks really did the job," says waterfowl biologist John Eadie, an author on the study. "They helped break down the straw, and were as effective or more effective than alternative methods such as chopping, disking or wet-rolling." In the study, experimental rice plots were harvested, flooded and either wet-rolled or left untilled. Mallard ducks were then allowed to forage on half of the experimental plots, says UC Davis graduate student Jeff Bird, who conducted the study. At the end of the experiment, the ducks had increased straw decomposition by 78% in the untilled plots and by 18% in the wet-rolled plots. The birds may bring other benefits to rice farmers, by getting rid of insects and weed seeds, and reducing the need for herbicides, says Bird. UC Davis is now conducting a much larger study on farms across the northern Sacramento Valley to investigate these potential benefits. "There's a real potential for win-win here," says Eadie, "with a lot of interest from local farmers." As well as breaking down straw and potentially reducing pests, fields managed in this way would provide habitat and attract more waterfowl. The study is published in the October issue of the Journal of Applied Ecology. Burning of rice straw is being phased out under California state legislation.