Monday, January 7, 2008

More Bird-friendly Window Treatments

Just a quick update on my window-collisions research:

I've heard from several more people who have tried the highlighter with pretty good success.

Continuing my own experiments here I've had over a month of 100% success with an array of monofilament stretched between two wooden boards outside the window. The monofilament is suspended a couple of inches in front of the window in vertical lines about three inches apart. It is very inconspicuous from inside, and has worked perfectly under some very busy conditions. I have some other experiments lined up to try, including a more streamlined version of the monofilament.

I also wanted to pass along a very promising suggestion from Diane Salter of Canada, who says:

Attached is a photo of something I've been using on my windows which is very effective. My house has windows totally covering front & back. Most of the windows I netted (as I have wooden frames) but that was impossible on sliding doors & the very high upper windows.

This is the clear (with patterns) wrapping that stores use for gift packages. It sticks by static (on the inside) & can be removed easily by just pulling it off. I found that the light coloured patterns work best. It makes a visible barrier & doesn not block your view out the window altho not as beautiful (or deadly) as clean sparkling windows. It comes in big rolls, around 40" wide & a roll will do lots of windows. My house has 36 major windows + 2 sliding doors & I had plenty in one roll. It needs replacing every couple of years as it starts to lose its grip.

It really does work. I rarely have bird strikes & when I do it's only a glancing blow. Currently I have 80+ redpolls, 100+ juncos & numerous other species at my feeders.

Finally, to report some negative results, about four weeks ago I tried drawing vertical lines on the outside of the glass with a black permanent marker, but that had no effect - still lots of collisions. It might work in some situations, but not here.


heidi said...

I never did ask how far apart your lines were - I tried standard 1" masking tape vertical stripes every four inches and still found that panic flights (common in winter due to accip. presence) would still leave a few critters dead. Not as many as before of course, but still..

David Sibley said...

The lines I drew were about 3" apart, and I think Klem's research showed that lines 4" or less should be effective. One of the interesting observations in his June 2009 paper was that a collision happened at a window covered with CollidEscape film, which suggests that birds might fly into anything! The panic flights you mention are probably going to be an issue with any window covering.

heidi said...

Heh, yeah. I worked at a zoo that lost a panicked bird on occasion due to flying into solid surfaces (eg, brick wall, wooden fence, a tree trunk), which suggests that panic flight is just that - panic without much thought or direction (or perhaps ability to control it?)