Is the fulvous whistling-duck a threat to the rice crop at Kibimba scheme, Eastern Uganda?

Abstract

The effect of the Fulvous Whistling-Duck (Dendrocygna bicolour; FWD) on the crop at Kibimba rice scheme, eastern Uganda, was investigated using both field methods and diet composition. Data were collected from 31 plots of 4ha each established on newly-seeded fields. Three, 3x3m exclosures (experimental treatment) and non-enclosures (control treatment) were placed randomly in each plot. We counted the number of rice seeds and the number of FWDs in the plot on three consecutive days after seeding. The number of rice plants in the experimental treatments was then counted six weeks later. A significant difference in the number of FWDs existed across the three days which was not the case for the number of rice seeds. The number of rice plants did not vary between treatments. Rice (Oryza sativa) and grass weeds (echinochloa spp) contributed 50.5% and 16.3% of the overall diet in dry weight, respectively. Results of this study indicate that FWDs appear not to be a threat to the rice crop at Kibimba. On the other hand, the presence of weed seeds in the FWD diet suggests that these birds may perform an ecosystem service of controlling weeds on rice farms.