Expert: Roger Lederer - 6/22/2006

Question
For the past several weeks, my parents had a finch visit them for
an several hours or so at a time. This finch sits on the window
sill of their bedroom window and pecks lightly on the glass, as
well as watches them and flies to other windows on the house
when they move to other rooms. My parents have said that if the
finch isnt pecking on the window, it's just staring at them in
whatever room they are in! Have you ever heard of such behavior
from a wild bird? If so, I would like to know. Thanks.

Answer
Cardinals, finches,robins and many other birds are territorial and when they establish territories in the
spring they become aggressive and chase off intruders. Unfortunately, they don't distinguish between their own reflection in a window (or car mirror) and try to chase that off. The solution to the problem is to eliminate the reflection. Misting the outside of the window with a very weak detergent or soda solution will eliminate the reflection but will also impair visibility for you. Awnings, eave extensions, and window screens will eliminate all reflection and stop the collision problem. Hanging ornaments such as wind chimes, wind socks, and potted plants also help. The behavior will stop when nesting ends. Roger Lederer at Ornithology.com