Abstract
As a Biodiversity Management Plan in S. Korea, barley fields are being prepared for the wintering migratory birds. However, the effectiveness of barley fields as a feeding habitat has not been evaluated. In 2003/04 wintering period, we installed exclosures in the barley fields to evaluate the waterfowl grazing effectiveness. Approximately 8,000 waterfowls used the Dongup Reservoir System and utilized the barley fields during the daytime. The white-fronted goose Anser albifrons occupied more than 90% of the all barley-feeding waterfowls. Waterfowls significantly impacted to the shoot density and biomass of barley. In the closed plot, barley shoot density gradually increased to $267{\pm}27/m^2$ in January, 2004. Shoot density in open plots (site 1) declined sharply from.15 December ($189{\pm}18/m^2$) to 5 January 2004 ($25{\pm}11/m^2$). However, barley shoot density in open plots (site 2) was stable in January 2004 because of human disturbances. The changes in barley biomass and shoot density showed similar trend in both open and closed plot. From the exclosure experiment, it was clear that barley fields were important feeding habitat for wintering waterfowls in this area. Further, human disturbances such as noise from traffic and other human activities (farming and hiking) had significant impact on waterfowls' grazing activity. Collectively, winter barley fields were effective for waterfowl feeding, but the location of barley fields should be carefully selected for the maximum utilization of the barley feeding.
