If you have mallard ducks landing in your pool are the duck droppings harmful?

Duck droppings are harmful if allowed to dry and harbor a mould that when ingested will cause long term illness. Mainly small children are at risk. The droppings in the pool will be sanitised by the pool chlorine however I would like to see the level of chlorine sanitiser at around 5ppm to be sure.

Also make sure to clean the filter often.