Foie Gras, Perhaps?
Dear Adorable Ducklings, While I admire your fluffy, cute feathers and am thankful you have not lost your lives to any roaving feral felines, I would greatly appreciate if you would not continue to leave your droppings all over the bottom of the pool. It is gross. Plus, there are a multitude of other places where you can eliminate pesonal waste without rendering my swimming area unusable. If you are unable to meet this request of mine unaided, then perhaps I could assist in finding you another role to play in this great big world of ours. Please respond with your decision before school is officially out for the summer. I anticipate my patience will have worn out by that point. Sincerely, RL