Science - October 18, 2018

Fish and ducks improve rice farming

Albert Sikkema

Combining rice farming with fish, ducks and water ferns make it more robust than a monoculture of rice. This conclusion was drawn by Uma Khumairoh, a PhD candidate in Farming Systems Ecology, from research in Indonesia. Her findings have been published in Nature Scientific Reports.


Climate change is causing an increase in extreme weather conditions, with more flooding and drought around the world. This makes countries such as Indonesia vulnerable, notes Khumairoh. Heavy rains and drought between 2013 and 2016 led to an increase in rice imports in Indonesia. The extreme weather conditions cause an increase in weeds, diseases and pests. Switching to a more robust method of growing rice seems advisable.

Khumairoh compared the mixed cultivation of rice, fish, water ferns and ducks with conventional and organic rice production in four regions of Indonesia. Conventional rice farming proved to deliver high yields in good weather, but production plummeted under extreme weather conditions.

Extreme weather conditions

Khumairoh discovered that organic rice farming had lower yields across the board, but they were less affected by bad weather. The combination of crops and products gave the highest average yield. Under favourable conditions, the combination produced a similar yield to that of conventional rice farming, but under extreme conditions it performed much better.

In the complex mixed system, just as in organic farming, no artificial fertilizer or crop protection products are used. Duck poo and water fern provide the nutrients for rice farming, while the movements of the fish and ducks help improve the nitrogen absorption of the roots of the rice plants. And the ducks and fish create an environment in which the natural enemies of rice pests can establish themselves. Therefore, Khumairoh concluded that the mixed system is more robust than a monoculture of rice, published in Nature Scientific Reports.