I own a vineyard in Sonoma County in Northern California. On the vineyard, I have a irrigation reservoir that is 2 surface acres when full, and decreases in size as water is used to irrigate the vines during summer months. (see attached picture). Geese have moved in and now stay year round, sometimes as many as 30 -40 at a time, especially in winter and spring. Their droppings make a mess and they are contributing to a growth of algae and aquatic plants that have made a once pristine reservoir dark and cloudy. Someone has suggested that I get 1 or possibly 2 swans (not sure which type best?) and that the swan(s) will drive the geese away and help keep the reservoir waters clear. They also suggested that I get a floating island with plants to help keep the waters clear and provide a nesting place for a swan or two.
I would appreciate any comments or advice on these suggestions. Thanks.