Rethinking airport land-cover paradigms: agriculture, grass, and wildlife hazards

The various habitats that compose airport property, particularly undeveloped lands, inherently contribute in some measure to attraction of wildlife and, subsequently, the risk of wildlife–aircraft collisions. Many airports control large tracts of land outside airoperations areas for safety and security and to mitigate noise pollution. In the contiguous United States, the average size of airports that are approved for regularly scheduled passenger traffic (i. e., certificated) by the Federal Aviation Administration (FAA) is 761 ha (DeVault et al. 2012). Although airports operate under numerous constraints when selecting land covers (Federal Aviation Administration 2012), turf grasses (managed, domesticated grass varieties) and other herbaceous plants are common and widespread. Depending on airport type, 39 to 50% of airport properties in the contiguous United States are covered by grasses (DeVault et al. 2009, 2012), most of which is mowed periodically but not harvested for hay. Many interpret airport grasslands, especially when maintained at about 15 to 25 cm in height by mowing, as the safest possible land cover with regard to its degree of attractiveness to bird species that are hazardous to aircraft (Seamans et al. 2007). However, this assumption has not been addressed adequately (Blackwell et al. 2013), and, in the absence of reliable data on alternatives, the widespread use of such grasslands as a land cover has become standard practice at airports