We live on a housing estate. Our kitchen door to the garden is half glazed. About 5 metres away is an out building with glazed patio doors but you can’t see in because of full length curtains.
About a week ago we noticed a blue tit behaving oddly. It flies at the kitchen door, or sits on the handle and taps with its beak or sits on the sill and taps the glass.
My first thought it was finding insects because we have a dog and the back door is always covered in mud. However once its done tapping on the kitchen door it flies to the out building and does the same. No mud there.
What’s it reason?