How interesting. I too had some experience using real bird droppings on some of my models this year during our Northern Hemisphere Spring. I can't say that I was all that enthused about it though. I discovered the "presents" in my workshop and noted that some "deposits" had been made on several of my model locos and some cars. Alas, I, in my ignorance, was unaware of the use of this substance for weathering, so I cleaned everything and forgot about it. Someone must have left the door open and a bird had got in, I thought. Two days later - - more deposits had been made to the account. Again, cleaned up. Next afternoon - - more deposits. What the hell is going on here?
The next day was a 'work in the workshop all day' day, and it was then that the mystery was solved. It seems that a pair of wrens had been he-ing and she-ing in the vicinity and had decided to set up housekeeping in my workshop. Somehow they had discovered that they could come and go by wriggling under the door and around the rubber threshold that makes the weather seal, and had built a nest up high on top of some cabinetry that is over my workbench.
Well, I didn't like the idea of them using the door that way, since the cat likes to camp out at that spot, and I was certain that she would ruin their day sooner or later. Entry and exit by such a method is blind, as the threshold is a piece of thick rubber that is contained in a shoe with weather stripping to keep it from drafting. You go through on faith, not knowing what lurks on the opposite side until you are through, very dangerous if you happen to be a bird and there is a cat on the other side.
So, I blocked the bottom of the door, and opened the upper sash of a window about two inches and pegged it so that it wouldn't move. The "couple" quickly discovered the new entry and began using it instead. After that I did not observe the birds trying to use the door. They were happier with the window arrangement. I moved stuff around to make them a flyway so that they wouldn't crap on my models any more and we were all happy until the chicks were fledged. Chicks left home, "mom & pop" split and I cleaned up the nest. Not that I don't like birds, mind you, but I am going to have to figure out a way to prevent them from moving back in next year. Putting up a birdhouse is not the answer, since the more houses you build, the more birds you attract. I'm thinking, maybe I can figure out a way to hire one of the owls that live in the area to set up camp in plain sight of the door. Or maybe one of the Red-tailed hawks that live over at the edge of the wood near my property line.
Froggy,