Some ducks foraging on land regularly alternate their behaviors between feeding and bill-dipping into the water. I observed activities during foraging, including this switching, in captive White-faced Whistling Ducks, Dendrocygna viduata, under two conditions in which the distance between the water and food is different (sample images are available at the MOMO Video Archive web site, http://www.momo-p.com with the data no.: momo010929dv01b and momo010929dv02b). When the distance became greater, the total time spent feeding on grain, feeding on bread, bill-dipping, and the total of other behaviors, did not change, whereas the frequency of feeding on grain and bill-dipping decreased, and that of preening, increased with greater distance. Bout duration of feeding on grain and bill-dipping also increased when the distance became further. The increase of bout duration of feeding on grain was significantly longer than expected, while that of bill-dipping did not differ from expected. Considering the preening can be a displacement activity, the increase of bout duration of feeding could be caused by competition for feeding sites rather than optimal adjustment predicted by optimal central place foraging.