Birds Attack Car Mirrors

I started letting Momoko and Kit Kat park in the carport. They drive to school every day. And they both have problems backing into the driveway next to the carport. This works out good for them. But my car is now in the driveway. The birds are targeting it.

Every day the birds poop on my mirrors. I tried cleaning them right away. The birds come back multiple times a day and soil the mirrors. A quick fix was to put plastic grocery bags of the mirrors. That deters the birds. It also makes the car look bad.

I bought some spikes to put on top of the mirrors. They also work well. But they were hard to mount onto the mirrors. I had to use two-sided tape. That is hard to remove when I take the spikes off to drive the car. There has to be a better way.