Sometimes birds accidentally fly into windows as they cannot see the transparent glass and reflections on the surface of the glass can confuse them, making them think they are flying into open air. In other cases, bright lights or plants near the window can attract the birds, or there may be bird feeders near the windows and the bird may hit the window when trying to escape from a predator. Unfortunately the impact of hitting a window can stun the bird or cause serious injury and even death.
Birds may also attack their own reflection in glass thinking it is another bird. Species such as the Laughing Kookaburra, Little Raven, Grey Butcherbird and the Australian Magpie-lark have been seen to do this. This problem is particularly prevalent during the breeding season when birds can become competitive, but can occur at any time.
Little Ravens and other birds may also occasionally develop the habit of pulling windscreen wiper blades and windscreen rubbers from cars. Some kinds of rubber emit chemicals that are also found in decaying carcasses, and it is thought that this may be the cause of the behaviour as the scent of the rubber attracts the birds, thinking it is a food source. Magpie-larks can also sometimes be seen to remove fresh putty from window frames, which is thought to be used for nest-building purposes.
There are a number of things that you can do to prevent birds flying into glass and/or attacking their reflections:
Try covering the outside of the glass with a physical barrier such as shade cloth or opaque screens to remove any reflection. If netting is used please ensure it is white and a suitable gauge so that birds can see it easily and do not become entangled in it. A shade cloth, available at hardware stores, is a plastic mesh that allows you to see through, yet keeps the windows from having reflections.
Install anti-glare/anti-reflection screens/film over the windows or try outdoor blinds. If your car windscreen wipers are being pecked - cover your car (or just the sections being pecked) with a sheet or blanket, also try parking in a different spot where birds won't have access.
Ornaments, crystals, strips of cloth/ribbon/paper/mobiles and other objects in the window will help birds know they can’t fly through. Avoid hanging plants in front of windows which are in areas of high bird activity – this can further confuse the bird which may fly towards the plant looking for shelter. When covering the window/glass try to cover most of the surface (aim for spaces no larger than 10cm across).
Other solutions include "Frosting" or "etching" the glass, applying a decorative pattern or decorative non-reflective objects that uniformly cover the entire window or as much of the window as possible.
Close curtains to create an opaque appearance. Turn blinds in a ¾ position to create a striping effect (check that reflections are adequately reduced).
Bright flowers or bird feeders near the window or even fish tanks and mice/rat enclosures can attract birds so please move these and any other bird attractants well away.
Are any windows in your home oriented such that, from the outside, there is a clear view through the house and to another window looking to the outside? A bird may see this as a flight path and think it is a clear space to fly through. This can be changed simply by closing blinds, putting up a shade on the one window, or closing a door or similar obstruction which breaks the open view.
For example, a hawk shape cut from self adhesive paper can be used. These can be designed from outlines in a bird field guide. Predator shapes can help to scare birds away from the window area.
At night, use only low-intensity lighting. Use task lighting with lamp shades that direct the light away from the window
If a bird is attacking its reflection in your windows, see if it usually launches itself from the same perch in a nearby tree. If so, removal of this perch can help in combination with physically covering the glass and reducing reflection.
To prevent putty removal from newly installed windowpanes, cover the putty with masking tape to prevent access to the putty until it has hardened. Dry, hard putty is not accessible to birds.
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