Sunday, October 10, 2010

Fall Migration and Window Collisions - by Eileen Hagerman

This is the time of year in which we receive many telephone calls about small birds that have collided into people's windows. They are often confused with being a baby bird, but we can rule that out at this point, as "baby season" is over.

Often with window collisions, there is no visible injury: the bird is stunned and can often recover quickly. Other times, it can take longer. You may notice the bird appears puffed up or hunched over; in other cases, it looks like the bird has a broken neck (head is cocked upside down). It is actually not a broken neck, but a head injury where the symptoms are known as torticollisis, or "stargazing".(see photo below of Red-tailed Hawk). In any case, the bird can be gently placed into a cardboard box (such as a shoebox) with one or two small holes poked in the box for ventilation. Put the box in a dark, quiet place such a garage or a bathroom and allow it some time to recover. If after an hour or two the bird is still incapacitated, contact us or another rehabilitator for further assistance. Do not try to feed the bird, or give it water: a dark, quiet place, and some time are all it needs at this point.


Why does this happen? There are several reasons:

Vision: While it is fairly easy for most birds to avoid building and large objects, they can have difficulty perceiving transparent obstacles, such as windows and other panes of glass. Furthermore, when plants are displayed inside on a windowsill, this makes it look as if a safe flyway exists.

Migration (which is happening now): Adult birds, often mistaken as baby birds, are often found colliding into windows each fall. These birds are birds that have migrated back to our area. Tired after travelling perhaps a thousand miles, they are often confused by windows and/or lighted buildings. New York City is a major flyway for migrating birds, and in an attempt to reduce collisions at this time of year, NYC has instituted a "Lights Out" program to reduce the number of collisions.


Territory: While this situation usually happens in the spring, it is still worth mentioning.
Sometimes birds intentionally crash into windows (and side view mirrors of cars, glass doors, etc); this is usually territorial. There is either a nest nearby or the bird is seeing its reflection and defending its territory. Try to put something up to block his reflection, and they usually move onto something else.


What can you do to help? There are several steps you can take:
-Have bird feeders either far back in the yard, or within a few feet of the window. This leaves less room for the birds to fly; window strikes will occur at a slower speed and the bird is less likely to be hurt.
-Avoid placing plants on your windowsill, as this can be confusing to birds.
-Reduce window reflections by having screens or shades covering the window. Blinds are also helpful, as they can be moved to reduce reflections while still allowing you to see outside.
-Purchase items that help prevent window collisions>
*Collidescape: A thin transparent film that attached to the window. Visit this website for a demonstration on how it works.

Below are a few photos of birds that have come into our hospital after colliding with a window:

Top photo: This is a Red-tailed Hawk that collided through a picture window last Christmas Eve.
She shattered the window and took off half of her beak
(visible in the photo).
Unfortunately, after 4 months, due to damage
done to the bony core of her beak, structurally her
beak would not grow back and we had to make the
difficult decision to put her to sleep.

Second photo: Palm Warbler that collided into a window. This bird was released.



This is an example of "stargazing" - see how this bird is holding
his head cocked sideways?
This is a very young Red-tailed Hawk that came into our facility
after suffering head trauma. His recovery took a long time, and
at a crucial age developmentally, he became very accustomed to
people, growing up around them. He is one of our permanent
Education Animals (Baby) and can be seen any day in our outside aviary,
where he lives with his female friend, Lucky Lady.


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