| Popis: |
Wildlife-aircraft strikes threaten both human and animal safety and result in hundreds of millions of dollars per year in aircraft damage and lost flight hours. Large-bodied birds are especially hazardous to aircraft. However, given high-speed flight at low altitudes, military aircraft may be especially vulnerable to strikes and more susceptible to damage even when encountering small birds. We summarized all wildlife-aircraft strike records from Randolph Air Force Base (San Antonio, Texas) over a 25-year period and compared the number and cost of strikes across avian species and species groups. Because columbids (i.e., pigeons and doves) are among the most frequently struck species by both civilian and military aircraft and because several columbid species have demonstrated marked population increases over the past decade, we also quantified characteristics (i.e., month, time of day, precipitation patterns, phase of flight, altitude) of columbid strikes. White-winged doves (Zenaida asiatica) have undergone a substantial northward range expansion over the past 60 years and are now numerous in San Antonio. Given local interest, we also highlighted characteristics of aircraft strikes involving this species. Though columbids were not the most frequently struck species group during the survey period (1990–2014), they were the most costly. Columbid strikes were more frequent from May to July than during other months and often occurred during morning hours, especially from 08:00–10:00, with a smaller afternoon peak from 15:00–17:00. Columbid strikes occurred during landing more than during other phases of flight, typically at ≤152 m above ground level (AGL), though white-winged doves were more likely to be struck on takeoff than expected. To reduce costs and safety concerns where columbids are prevalent, military flight planners, aircrews, and wildlife managers can reduce air travel, increase vigilance during takeoffs and landings, and implement on-the-ground hazing techniques in morning and late afternoon hours during spring and summer months. |
