My poor window...

Falcons Sniper and Petrusha like very much to sit on the windowsill. I would not mind if it did not create a delicate problem ... They not only sit there. They somehow manage to shit on the window! Because of this, the glass is terribly dirty. But that's not all. Bird droppings are very very difficult to clean! It sticks to any surface mortly. Probably I will have to think about finding another place for them, and put into this enclosure those birds whose shit does not fly!