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

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Figure 1. A walkway connecting two buildings at Washington State University where one of the earliest studies of bird collision mortality found 85 bird fatalities per year prior to marking windows (254 annual deaths adjusted for the proportion not found). Given that the window markers have long since disappeared, this walkway has likely killed at least 12,7o5 birds since 1968, and continues to kill birds. Notice that the transparent glass on both sides of the walkway gives the impression of unimpeded airspace that can be navigated safely by birds familiar with flying between tree branches. Also note the reflected images of trees, which can mislead birds into seeing safe perch sites. Further note the distances of ornamental trees, which allow birds taking off from those trees to reach full speed upon arrival at the windows. Window collisions are often characterized as either the second or third largest source or human -caused bird mortality. Loss et al. (2014) estimated that window collisions cause 365-988 million bird fatalities in the USA. Homes with birdfeeders are associated with higher rates of window collisions than are homes without birdfeeders (Kummer and Bayne 2015, Kummer et al. 2o16a), so the developed area might pose even greater hazard to birds if it includes numerous birdfeeders. (The Staff Report is silent on this possibility.) Another factor potentially biasing the national estimates low was revealed by Bracey et al.'s (2o16) finding that trained fatality searchers found 2.6x the number of fatalities found by homeowners on the days when both trained searchers and homeowners searched around homes. The difference in carcass detection was 30.4-fold when involving carcasses volitionally placed by Bracey et al. (2016) in blind detection trials. This much larger difference in trial carcass detection rates likely resulted because their placements did not include the sounds that typically alert homeowners to actual window collisions, but this explanation also raises the question of how often homeowner participants with such studies miss detecting window -caused fatalities because they did not hear the collisions. By the time Loss et al. (2014) performed their effort to estimate annual USA bird - window fatalities, a minimially sufficient number of fatality monitoring studies had been reported or were underway. Loss et al. (2014) were able to incorporate estimates of fatality rates based on scientific monitoring. However, they included estimates based on fatality monitoring by homeowners, which in one study were found to detect only 38 of the available window fatalities (Bracey et al. 2o16). Loss et al. (2014) excluded all fatality records lacking a dead bird in hand, such as injured birds or feather or blood spots on windows. Loss et al.'s (2014) fatality metric was the number of fatalities per building (where in this context a building can include a house, low-rise, or high-rise structure), but they assumed that this metric was based on window collisions. Because 0