Bird-Friendly Building Design Bird-Friendly Building Design

More documents

Recommendations

Info

The number of birds killed by collisions with glass every year is astronomical.36 Bird-Friendly Building DesignHundreds of species of birds are killed by collisions. These birds were collected by monitors with FLAP in Toronto, Canada. Photo: Kenneth Herdy
APPENDIX I: THE SCIENCE OF BIRD COLLISIONSMagnitude of Collision DeathsThe number of birds killed by collisions with glass everyyear is astronomical. Based on studies of homesand commercial structures, Klem (1990) estimatedconservatively that each building in the United Stateskills one to ten birds per year. Using 1986 UnitedStates Census data, he combined numbers of homes,schools, and commercial buildings for a maximumtotal of 97,563,626 buildings. Dunn (1993) surveyed5,500 people who fed birds at their homes and recordedwindow collisions. She derived an estimateof 0.65-7.7 bird deaths per home per year for NorthAmerica, supporting Klem’s calculation.The number of buildings in the United States hasincreased significantly since 1986, and it has beenshown that commercial buildings generally kill morethan ten birds per year, as would be expected sincethey have large expanses of glass (Hager et al., 2008;O’Connell, 2001). Thus, one billion annual fatalitiesis likely to be closer to reality, and possibly even toolow.Klem et al., (2009a) used data from New York CityAudubon’s monitoring of seventy-three Manhattanbuilding facades to estimate 0.5 collision deaths peracre per year in urban environments, for a total ofabout 34 million migratory birds annually collidingwith city buildings in the United States.Patterns of MortalityIt is difficult to get a complete and accurate pictureof avian mortality from collisions with glass. Collisiondeaths can occur at any time. Even intensive monitoringprograms only cover a portion of a city, usuallyvisiting the ground level of a given site at most oncea day and often only during migration seasons. Manycity buildings have stepped roof setbacks that areinaccessible to monitoring teams. Recognizing theselimitations, some papers have focused on reportsfrom homeowners on backyard birds (Klem, 1989;Dunn, 1993) or on mortality of migrants in an urbanenvironment (Gelb and Delacretaz, 2009; Klem et al.,2009a, Newton, 1999). Others have analyzed collisionvictims from single, large-magnitude incidents (Sealy,1985) or that have become part of museum collections(Snyder, 1946; Blem et al., 1998; Codoner, 1995).There is general support for the fact that birds killedin collisions are not distinguished by age, sex, size,or health (for example: Blem and Willis, 1998; Codoner,1995; Fink and French, 1971; Hager et al., 2008;Klem, 1989). However, some species, such as theWhite-throated Sparrow, Ovenbird, and CommonYellowthroat, seem to be more vulnerable than others,appearing consistently on top ten lists. Snyder(1946), examining window collision fatalities at theRoyal Ontario Museum, noted that the majority were“tunnel flyers” – species that frequently fly throughsmall spaces in dense, understory habitat. Recentwork (J. A. Clark, pers. comm.) suggests that theremay be species differences in attraction to light thatcould explain these findings. Interestingly, specieswell adapted to and common in urban areas, such asthe House Sparrow and European Starling, are notprominent on lists of fatalities, and there is evidencethat resident birds are less likely to die from collisionsthan migratory birds.Collision mortality appears to be a density-independentphenomenon. Hager et al. (2008) comparedthe number of species and individual birds killed atbuildings at Augustana College in Illinois with thedensity and diversity of bird species in the surroundingarea. The authors concluded that total windowarea, habitat immediately adjacent to windows, andA sample of collision victims from Baltimore.Photo: Daniel J. Lebbin, ABCBird-Friendly Building Design37
Page 1: Bird-FriendlyBuildingDesign
Page 4 and 5: Issues of cost prompted Hariri Pont
Page 6 and 7: Introduction
Page 8 and 9: architects to mark the beginning of
Page 10 and 11: Problem: GlassThe glass in this Was
Page 12 and 13: Large facing panes of glass can app
Page 14 and 15: Plantings on setbacks and rooftops
Page 16 and 17: Solutions: Glass
Page 18 and 19: FOA made extensive use of bamboo in
Page 20 and 21: Awnings and OverhangsOverhangs have
Page 22 and 23: Patterns on GlassPatterns are often
Page 24 and 25: Opaque and Translucent GlassOpaque,
Page 27 and 28: This window at the Philadelphia Zoo
Page 29 and 30: Artificial light is increasingly re
Page 31 and 32: Reducing exterior building and site
Page 33 and 34: Downtown Houston during Lights Out.
Page 35: Changing human behavior is generall
Page 39 and 40: species - is still being investigat
Page 41 and 42: Both increased height of trees and
Page 43 and 44: argument that patterns applied to t
Page 45 and 46: APPENDIX II: BIRD MIGRATIONBird col
Page 47: Night-migrating songbirds, already
Page 50 and 51: The white stripes on this glass wal
Page 52 and 53: Madrid’s Vallecas 51, designed by
Page 54 and 55: REFERENCESAvery, M.L., P.F. Springe
Page 56 and 57: External shades, as shown here on t
Page 59: The Orange Cube, a commercial and c

Bird-Friendly Building Design Bird-Friendly Building Design

Create successful ePaper yourself

Delete template?

Save as template?