April 29, 2014

Protecting birds from death by collision with windows


Bird lovers had an exciting winter at Ocracoke this year. Not only were we gifted with the presence of snowy owls wintering far south of their typical range, but we also saw unusually high numbers of cedar waxwings migrate through the village.

Dressed in black masks, with silky brown and yellow plumage and capped with perky crests, they descended upon the berries offered up by our native trees.   They seemed to perform choreographed ballets as they soared through the sky, and their cheery forms, perched on the branches of cedar and wax myrtle trees, resembled ornaments on a well-decked-out Christmas tree. 

Sadly, however, many of these delightful birds met untimely deaths here. Some were hit by cars, others killed by cats, a few shot illegally by budding young hunters with BB guns. Most, however, died as a result of collisions with the windows in our buildings. 

This was not unusual. Collisions with human structures are believed to be the main cause of death for passerines, or song birds, second only to loss of habitat.

It is estimated that somewhere between 300 million and a billion birds die each year in this country due to collisions with man-made structures. While cell towers and windmills take a heavy toll, the biggest threat is glass windows. Most of the deaths occur during spring and fall migrations, as was the case this spring with the cedar waxwings, and most of the victims are song birds.

All kinds of birds are liable to fly into windows, however, at all times of the year.

“Birds do not perceive conventionally formulated glass as a solid barrier,” according to the American Bird Conservancy. 

In other words, they are not able to detect glass as an obstacle, and reflections of trees or other natural landscapes in our windows often entice them to fly into the glass. Many birds migrate at night, and they are attracted to and distracted by outdoor lights and lights inside of buildings, leading to collision deaths. Many die instantaneously, and even those which fly away may die later as a result of the injury. 

There are ways to prevent these small but heart-breaking tragedies, and there are a number of organizations devoted to letting people know about these ways. The American Bird Conservancy oversees a “Bird Collision Campaign,” dedicated to educating people on how to make the windows in their homes and businesses bird-safe.  The Canadian organization “Fatal Light Awareness Program” (FLAP) focuses on preventing collisions caused by unnatural lights. The company Feather Friendly Technologies has been working with bird experts for more than 10 years to create marketable solutions, 

As an incentive to builders, the U.S. Green Building Council offers “Leadership in Energy and Environmental Design” (LEED) guidelines and credits for those who build with bird-friendly materials and designs.

City and state governments are also getting involved in trying to save our feathered friends from death by collision.  Such cities as Portland, San Francisco, New York, Chicago and Toronto, as well as the state of Minnesota, are establishing bird-friendly building guidelines, and seven cities have signed a U.S. Fish and Wildlife Services “Urban Bird Treaty” designed to protect songbirds. A federal bill, introduced in the House in 2011 and again in 2013, died in committee, but it is hoped will eventually be passed.

Any bird lover who has heard the disturbing thud of a songbird hitting a window and discovered its lifeless body underneath, must surely want to prevent it happening again. Listed below are a number of ways this can be done.

Some things that do not work, according to FLAP, include silhouettes of hawks, plastic owls, and single window decals.

The following ideas will work, if implemented properly. Remember to follow the important 2- to 4-inch rule in all of the applications. Dots, stripes, ribbons, decals or other deterrents must be no more than 2 inches apart horizontally or 4 inches apart vertically.  Also, remember that all applications must be placed on the outside of windows, even window films, which are designed to go on inside glass.

1. Replace present glass with bird-friendly glass, which is textured or appears opaque from the outside.  Orilux, described below, works well. Or apply a coating, such as Feather Friendly Retrofit Solution, which is visible to birds but not people. 

2. Apply window designs with a brush or sponge, using permanent markers or tempera paint, or with a stencil.

3.  Place opaque tape on the glass in attractive patterns, or use specially made ABC Bird Tape which transmits light.

 4.  Apply interior window films of various colors and styles to the OUTSIDE of the windows. Artistic window film, which can be purchased at hardware or glass/mirror stores, is attractive and works well as long as the 2- to 4-inch rule is followed. A perforated window film called CollidEscape looks opaque from the outside but resembles window screen from the inside. It works well in daylight but is not effective at night. 
5.  Attach lightweight netting outside the window. The netting must be placed several inches away from the window so the bird does not hit the window through the netting.

6. Place screening on the outside of the glass.  Specially made screens for saving birds which can be put up with suction cups or eye hooks are available at www.birdscreen.com or www.birdsavers.com.

7. Apply decals, placed close together, on glass windows.  Specially made Windowalert decals work well, as described below.

8. Hang ribbons, pinecones, or other decorations on the outside of windows, making sure that they are close together.
9. Modify light regimes, which includes keeping interior lights off at night when possible, and situating exterior lights so that they are angled down and away from the sky.

10. Relocate bird feeders and baths to within 1 feet or less from windows, so that birds do   not build up enough speed to injure themselves if they hit the glass.

11. Move indoor house plants away from windows so that they cannot be seen from outside.

12. Install exterior window awnings.

Researchers are developing ways to take advantage of the fact that birds see more ultra-violet (UV) colors than humans. Orilux, a window glass recently developed in Germany, which uses UV colors and reduces collisions by 71 percent, was selected as one of the top ten most exciting green building products in a recent Green Building Conference in Chicago.  Windowalert decals, which follow the same principle, using UV colors, work well as long as the 2- to 4-inch rule is followed.

FLAP and Feather Friendly Technologies worked with the town of Markham to test the success of using bird-safe window film on buildings and found that they reduced bird collisions by 97 percent.

Experts at the American Bird Conservancy stress that “You can save birds from flying into your windows.” 

The time to begin modifying your home or other structures is before fall and spring migration times arrive. If you plan to build or add on to your present structures, incorporate bird-friendly guidelines into the plans. Or choose one or more of the suggestions listed above to modify windows already in place and reduce your lights during evening hours.

The small, fragile creatures we call songbirds, many of which are listed as endangered or threatened species, perform incredible feats as they migrate hundreds or thousands of miles each spring and fall.

They encounter an untold number of dangers on the way. Let’s do everything we can to make their journeys easier, and to make their stop-overs on the Outer Banks safe refuges.

The bird-friendly items can be ordered online by going to the American Bird Conservancy, Feather Friendly Technologies, birdsavers.com or birdscreen.com. Some are also available at bird stores.

If you do find a bird injured in a collision, place it in a dark safe space, such as a small box or paper bag, with a few holes for air. If it revives and seems strong, release it. If after a few hours it is still alive but unable to fly get it to a wildlife rehabilitator. 

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