[inland-NW-birders] Re: [Tweeters] Windows: the "ghost nets" of land

Kelly Cassidy lostriver at completebbs.com
Tue Aug 24 21:40:47 PDT 2010

Klem is doubtful that many of the current glass coatings on the market are effective. He did find an experimental film with a UV pattern that was effective in his research. The films are fairly pricey and would probably need reapplying in a few years. They reportedly dramatically reduce the amount of light transmitted, which makes for dark rooms.

But mostly, the problem is that a miniscule percentage of windows treated with film won’t make much of a difference. There IS, after all, an old-fashioned technology that works, namely ordinary insect screening on the outside of the window. And yet, you hardly ever see window screens anymore. Most buildings nowadays have climate controls and windows are rarely opened. The screens block the view and collect dust.

I think the only effective solution would be legislation to require new glass to be made so it is visible to birds. Only then will there be an incentive to find a manufacturing process that works and doesn’t cost a fortune.

Kelly Cassidy

From: inland-nw-birders-bounces at uidaho.edu [mailto:inland-nw-birders-bounces at uidaho.edu] On Behalf Of Guy McWethy
Sent: Tuesday, August 24, 2010 8:56 PM
To: tweeters at u.washington.edu; 'Inland NW Birders'; Kelly Cassidy
Subject: [inland-NW-birders] Re: [Tweeters] Windows: the "ghost nets" of land

Here you go.
Window coatings to make them more visible to birds, but invisible to humans ...


Guy McWethy
Renton, WA
mailto: lguy_mcw at yahoo.com

--- On Tue, 8/24/10, Kelly Cassidy <lostriver at completebbs.com> wrote:

From: Kelly Cassidy <lostriver at completebbs.com>
Subject: [Tweeters] Windows: the "ghost nets" of land
To: tweeters at u.washington.edu, "'Inland NW Birders'" <inland-nw-birders at uidaho.edu>
Date: Tuesday, August 24, 2010, 6:29 PM

Ghost nets are lost, drifting fishing nets that continue to kill animals that get entangled in them.

On the Washington State University campus, there is a glass-enclosed walkway between the 2nd, 3rd, and 4th floors of Heald and Abelson. I work in the museum in Abelson. The walkway has long provided a steady source of birds for the museum, one that we would rather not have. It is an indiscriminate killer.

August 18, I picked up a dead Wilson’s Warbler from below the walkway. As I was entering it into our record book and bagging it for the freezer, I saw that Dick Johnson and Paul Schroeder had added 2 Wilson’s Warblers from below the walkway, both on August 5. An hour or so later on August 18, I picked up yet another Wilson’s Warbler from below the walkway.

I don’t normally check under the walkway for birds; I only pick them up when I happen to see them. With such a high number of Wilson’s Warblers in a short period of time, I started doing more deliberate searches and trying to remember to check every couple of hours or so.

This morning about 9:30, I picked up yet another Wilson’s Warbler. (They must be in a migration peak.) About 10:30, I was talking to someone under the walkway we had said “A bird just fell to the ground behind you.” This victim was a Red-breasted Nuthatch that was still alive, but stunned. I put him in a covered bird cage in a dark room. I was not optimistic, as most birds that aren’t killed outright in window kills have traumatic head injuries. I was pleasantly surprised when I checked on him an hour later. He was one of the lucky ones. He was flying around his cage, not having any obvious troubles with coordination or flying into the bars. I let him loose outside where he zipped way up in the air and disappeared.

Not long after that good outcome, I found a not-so-lucky dead sparrow. I had to carefully compare it with the museum specimens to ID it as a juvenile Chipping Sparrow.

Dr. Daniel Klem has been researching window-kills and how to prevent them since the 1990s. He has a website with links to recent research at:


The research is not encouraging, but the most discouraging aspect of window kills is the seeming apathy among conservationists. Klem (and others) believe that, after habitat loss, window strikes are the second largest human-caused killers of birds. In the US, windows passively kill hundreds of millions, maybe as many as a billion birds per year.

Turns out, the Heald-Abelson skywalk is the worst possible type of window situation, namely, it consists of large panes of glass near vegetation. (The huge glass skyscrapers are not nearly so deadly as windows closer to the ground at vegetation level.) Worse, birds can see vegetation on the other side of the skywalk from both sides.

I confess to apathy myself, probably for the same reason most other conservationists are apathetic to the situation. There is simply too much glass and too many people adding more glass every year.

Very depressing.

Kelly Cassidy

Pullman, WA

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