A picture taken at Vergenoegd wine estate on June 3, 2016 near Stellenbosch shows trained Indian Runner ducks in the vineyards.
The ducks eat snails and other pests which threaten the grapevines, allowing the farm to avoid using toxic pesticides, and they also fertilise the ground with their droppings. The ducks sleep in an enclosed pen, and are herded out to the vineyards in the day, then for a swim in the dam, and then back to their pen in the late afternoon. / AFP / RODGER BOSCH        (Photo credit should read RODGER BOSCH/AFP via Getty Images)