Landfills, nocturnal foraging, and risk to aircraft

Open landfills serve as an attractant to birds, with increasing risk of bird-plane collisions. Managers are searching for methods to allow landfilling while reducing potential bird problems near airports. Some municipalities are considering nighttime landfilling as an avian deterrent, particularly where waste management facilities are located near airports. The objective of this report was to evaluate whether nighttime landfilling will result in increased risk to aircraft from birds at the Atlantic County Airport in coastal New Jersey. The risk to nearby aircraft from nighttime landfill is a function of (1) attractiveness of landfills, airports, or other habitats, (2) nocturnal behavior of gulls and other birds, (3) elevations and flight paths of birds, (4) changes in population levels of gulls and other potentially hazardous birds, and (5) harassment techniques that can deter birds from the landfills, adjacent habitat, and airports. The latter, however, can serve to move birds to locations or altitudes that pose an even greater risk to aircraft. The number of strikes is generally increasing. While most air strikes occur during the day at the Atlantic County Airport, over 12% occur at night and nearly 20% occur at dawn when any garbage remaining from nighttime landfilling would be an attractant. The peak of strikes occurs in the early fall, when young birds are learning to forage. Risk data suggests that gulls and a wide variety of other birds are active at night, and if any garbage is available they will be attracted, increasing the risk to aircraft landing at night. Some actual night dumping has been carried out since October 3 1997 without apparently attracting gulls, suggesting that careful operations with appropriate institutional controls can make nighttime dumping feasible.