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

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Project Impact Prediction Predicting the number of bird collisions at a new project is challenging because the study of window collisions remains in its early stages. Researchers have yet to agree on a collision rate metric. Some have reported findings as collisions per building per year and some as collisions per building per day. Some have reported findings as collisions per m2 of window. The problem with the temporal factor in the collision rate metrics has been monitoring time spans varying from a few days to 10 years, and even in the case of the 10-year span, monitoring was largely restricted to spring and fall migration seasons. Short-term monitoring during one or two seasons of the year cannot represent a `year,' but monitoring has rarely spanned a full year. Using `buildings' in the metric treats buildings as all the same size, when we know they are not. Using square meters of glass in the metric treats glass as the only barrier upon which birds collide against a building's facade, when we know it is not. It also treats all glass as equal, even though we know that collision risk varies by type of glass as well as multiple factors related to contextual settings. But the recent flurry of studies of bird -window collision is what is available, and it helps that I have 21 years of experience with estimating mortality of bird collisions with other types of anthropogenic structures (Smallwood 2013, 2020; Smallwood et al. 2018). Without the benefit of more advanced understanding of window collision factors, my prediction of project impacts will be uncertain. Klem's (1990) often -cited national estimate of avian collision rate relied on an assumed average collision rate of 1 to to birds per building per year, but studies since then have all reported higher rates of collisions 12 to 352 birds per building per year. Because the more recent studies were likely performed at buildings known or suspected to cause many collisions, collision rates from them could be biased high. By the time of these comments I had reviewed and processed results of bird collision monitoring at 213 buildings and facades for which bird collisions per m2 of glass per year could be calculated and averaged (Johnson and Hudson 1976, O'Connell 2001, Somerlot 2003, Hager et al. 2008, Borden et al. 2010, Hager et al. 2013, Porter and Huang 2015, Parkins et al. 2015, Kahle et al. 2016, Ocampo-Penuela et al. 2016, Sabo et al. 2016, Barton et al. 2017, Gomez -Moreno et al. 2018, Schneider et al. 2018, Loss et al. 2019, Brown et al. 2020, , City of Portland Bureau of Environmental Services and Portland Audubon 2020, Riding et al. 2020). These study results averaged 0.073 bird deaths per m2 of glass per year (95% CI: 0.042- 0.102). Looking over the proposed building design, I estimated the buildings would include at least 17,991 m2 of glass panels, which applied to the mean fatality rate would predict 1,315 bird deaths per year (95% CI: 781-1,85o) at the buildings. The 100- year toll from this average annual fatality rate would be 131,514 bird deaths (95% CI: 78,o81-1$4,947)• The mortality would continue until the buildings are either renovated to reduce bird collisions or they come down. If the project moves forward as proposed, and annually kills thousands of birds protected by AB 454, the project will cause significant unmitigated impacts. As mentioned earlier, the accuracy of my window collision predictions depends on factors known or hypothesized to affect window collision rates. However, from the national average collision rate, I used all the variation in collision rates that was