Item 27 - Appeal Application Nos. 2020-03 and 2020-04 - Central Pointe Mixed-Use Development

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(1) Inherent hazard of structure in airspace. —Not all of a structure's collision risk can be attributed to windows. Overing (1938) reported 576 birds collided with the Washington Monument in 90 minutes on one night, 12 September 1937. The average annual fatality count had been 328 birds from 1932 through 1936. Gelb and Delacretaz (2oo9) and Klem et al. (20o9) also reported finding collision victims at buildings lacking windows, although many fewer than they found at buildings fitted with widows. The takeaway is that any building going up at the project site would likely kill birds, although the impacts of a glass -sided building would likely be much greater. (2) Window transparency. —Widely believed as one of the two principal factors contributing to avian collisions with buildings is the transparency of glass used in windows on the buildings (Klem 1989). Gelb and Delacretaz (2009) felt that many of the collisions they detected occurred where transparent windows revealed interior vegetation. (3) Window reflectance. —Widely believed as one of the two principal factors contributing to avian collisions with buildings is the reflectance of glass used in windows on the buildings (Klem 1989). Reflectance can deceptively depict open airspace, vegetation as habitat destination, or competitive rivals as self-images (Klem 1989). Gelb and Delacretaz (2009) felt that many of the collisions they detected occurred toward the lower parts of buildings where large glass exteriors reflected outdoor vegetation. Klem et al. (2oo9) and Borden et al. (2010) also found that reflected outdoor vegetation associated positively with collisions. (4) Black hole or passage effect. —Although this factor was not often mentioned in the bird -window collision literature, it was suggested in Sheppard and Phillips (2015). The black hole or passage effect is the deceptive appearance of a cavity or darkened ledge that certain species of bird typically approach with speed when seeking roosting sites. The deception is achieved when shadows from awnings or the interior light conditions give the appearance of cavities or protected ledges. This factor appears potentially to be nuanced variations on transparency or reflectance or possibly an interaction effect of both of these factors. (5) Window or facade extent.—Klem et al. (2009), Borden et al. (2010), Hager et al. (2013), Ocampo-Penuela et al. (2016), Loss et al. (2019), Rebolo-Ifran et al. (2019), and Riding et al. (2020) reported increased collision fatalities at buildings with larger reflective facades or higher proportions of facades composed of windows. However, Porter and Huang (2015) found a negative relationship between fatalities found and proportion of fagade that was glazed. (6) Size of window. —According to Kahle et al. (2016), collision rates were higher on large -pane windows compared to small -pane windows. (7) Type of glass.—Klem et al. (2009) found that collision fatalities associated with the type of glass used on buildings. Otherwise, little attention has been directed towards the types of glass in buildings. 10