Better check laws in your state, in many places, especially national parks and wildlife preservation areas it's illegal to remove a bird's nest, or even feathers. I think it's federal law that makes collection of Eagle feathers illegal, except for Native Americans. Ditto for many bird feathers, and the personnel at a wildlife management area in north Louisiana told me it's illegal to take a bird's nest. I don't know about on your own personal property, but check your local laws. I have bird boxes, those nests have to be cleaned out yearly, and as far as I know that's legal, it protects the future residents from parasites like lice and such.
If it's legal, try clear spray paint.