I have read about it in David Sibley's blog; you can look it up there 
(https://www.blogger.com/comment.g?blogID=8723269882919206612&postID=1559996808
53133331) I have been using a cake of plain soap to put marks on the outside of the window 
glass. It seems to work for me; I haven't had any strikes since I did it, but also my birdfeeder 
is on a adjacent tree and not very close to my windows. The marks of course wash off with 
time and have to be renewed.

Yesterday I went to Turners Falls just over the border in MA and took photos of an Iceland 
gull and a glaucous gull, which I put on my website 
(http://www.onejackdaw.com/new_birds.html). I also saw a flock of common goldeneyes, a 
solitary common loon, large flock of mallards and many mute swans, both adults and 
juveniles. It was worth the 20 mile trip from Brattleboro.

Hilke Breder 
Brattleboro
www.onejackdaw.com

> Has anyone heard about writing on a window with a yellow highliter to
> prevent the birds from inadvertantly flying into the glass?
> 
> Mundi
> Pownal