Preventing Bird Strikes
July 13, 2010
We have noticed an increasing number of birds hitting our windows lately, probably because this time of year there are a lot of juvenile birds that are encountering windows for the first time. We have tried the common hawk-shaped decals and they seem to help a little but not enough. There are other commercially-available products such as semi-transparent stickers that can be applied to windows to prevent birds from crashing into them but from what we have read, the stickers need to be quite close together (a few inches apart) in order to be effective. With so much south-facing glass it would be quite pricey to smatter stickers all over our big windows. There are a number of other solutions that people have tried with varying success, but we don't want to put anything in front of the windows that would serve as a ladder for squirrels to get to the bird feeders.
As an experiment, we decided to try using ordinary Scotch tape to make diamond patterns on the windows. This is the so-called "invisible" tape, which has a matte finish that is relatively invisible when applied to paper but shows up quite well when applied to glass. We don't expect the tape to last a long time because it is exposed to the elements, but it should last a while and it was very inexpensive. It's necessary to put it on the outside of the windows because it needs to break up the reflection of trees and sky that the birds see.
The photos below show the southeast-facing window that looks onto the deck, first from the outside and then from the inside. Looking at the reflection in the first photo you can see why a bird might be tempted to fly in that direction, but the crisscross pattern should be an effective deterrent.
Here are the big south-facing windows right by the bird feeders. These have gotten a lot of bird strikes, probably because the feeders draw the birds to this area, so they'll be a good test of how effective this technique is. Overall the effect is not bad, a bit like old leaded glass windows.
We only did these windows as a test and we'll monitor the birds' activity. If these windows get no bird strikes and the others still do, then we'll consider it a success and try to come up with a more permanent version that we can apply to all the windows.
September 21, 2010
After trying it for several weeks, we had almost no bird strikes on the taped windows. Birds occasionally still hit the windows after being startled off the bird feeders, but from only a few feet away they don't build up much speed and don't hit very hard, and it doesn't seem to hurt them. Surprisingly, the tape has held up very well even on those windows that get some direct sun. We went ahead and taped the other large windows on the house and cottage. Hopefully the tape will last through the winter so we can apply a longer-lasting solution next spring.