Not a major problem?

Our lake biologist as well as those making the alum presentation didn't seem to feel geese are a major source of nutrients for the algae in our lake. They are the experts but I have to tell you, common sense dictates otherwise.
This morning once again when I arose early and looked at the lake the east end was black with geese. Some of the area in which they were standing had frozen again into a thin sheet of ice. After they left I looked out about eight a.m. and the ice was so covered with goose droppings so thick I at first wasn't even sure what it was. Add that to all the same material left all around the lake on land that runs into the lake with rain and it is like dumping fertilizer into our lake.
What do we do? I know of nothing truly effective. Lake management is addling eggs but that is a drop in the bucket. I guess this is just part of living in a lake community.
The aerators running provide a large open water area for the geese so we live with it.
Ken