[Tweeters] Stop Window Strikes

Ann Marie Wood amw.5737 at gmail.com
Fri May 27 14:57:22 PDT 2016

These are also available in the Seattle Audubon Nature Shop on 35th NE.

Whenever possible I prefer to support this local non-profit organization.

Ann Marie Wood

Sent from my iPhone

> On May 27, 2016, at 1:48 PM, Christine Southwick <clsouth at u.washington.edu> wrote:


> Yesterday I saw the square decals at my local Fred Meyer next to the birdseed. Didn't notice the price as I was in a "grab the seeds and pay mode".


> Christine Southwick

> N Seattle/Shoeline

> clsouthwick at q.com




>> On Fri, 27 May 2016, Neil Johannsen wrote:


>> Date: Fri, 27 May 2016 12:22:08 -0700

>> From: Neil Johannsen <neil.johannsen at gmail.com>

>> To: tweeters at u.washington.edu

>> Subject: [Tweeters] Stop Window Strikes

>> Bird Lovers:

>> An estimated 100 million birds die each year from window strikes. Most of us have experienced the heart-breaking thud sound, or found dead birds below our windows.

>> The death of a beautiful Golden-crown Sparrow set me hunting for the best solution a week ago - to end the carnage.

>> For the sake of others in our group,I found this: windowalert.com. It’s a product from Bend. Oregon. I have no financial relationship with this company; i simply want to

>> save bird lives.

>> What I learned:

>> Birds can see certain light frequencies--including ultraviolet--that humans cannot see.

>> In fact, many songbirds have feathers that reflect ultraviolet light. This light is used to communicate species, gender, and perhaps even social standing. Birds can see

>> this ultraviolet light under normal, daylight conditions. Humans require the assistance of a black light.

>> Why?

>> 1) Both birds and humans have photoreceptive 'cones' in the retina located at the back of the eye. These cones allow us to see color light. The human eye contains 10,000

>> cones per square millimeter. Songbirds, for example, have up to 12 times this amount or 120,000 cones per square millimeter.

>> 2) In humans, these photoreceptive cones consist of three types. Each cone is sensitive to red, green, or blue light. This is called trichromatic color vision. Birds have

>> an extra cone for tetrachromatic color vision. This extra cone expands the visible light spectrum, allowing birds to see ultraviolet frequencies.

>> 3) During low-light conditions, both humans and birds rely on photoreceptive ‘cell rods’ in the retina. The human eye has 200,000 cell rods per square millimeter. Some

>> birds, such as owls, have up to 1,000,000 cell rods per square millimeter.

>> 4) Bird eyes, on average, account for 15% of the mass of the bird’s entire head. Human eyes, by contrast, account for less than 2% of the head.

>> 5) Bird retinas, in contrast to humans, contain no blood vessels. This prevents light scattering and thus provides birds with greater visual acuity than humans.

>> The decals are very non-conspicuous; after a while, you may not even notice them, but birds will!

>> Thank you all,

>> Neil C. Johannsen

>> Kitsap Audubon


> Christine Southwick

> Pharmacy Administration

> University of Washington Medical Center

> Box 356015

> 1959 NE Pacific Street

> Seattle, WA 98195-6015

> phone: 206-598-7398; fax 206-598-6075




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