USDA National Wildlife Research Center Symposia



John R. Allan

Date of this Version

August 2000


Collisions between birds (and other wildlife) and aircraft are known to cause substantial losses to the aviation industry in terms of damage and delays every year. Techniques exist to control bird numbers on airfields and hence to reduce the number of wildlife strikes, but they are applied at widely different levels from airport to airport. Some of this variation may be due to differing levels of strike-risk at the different sites, but much of it is due to the unwillingness or inability of the airports concerned to invest in bird strike prevention. Part of the reason for this reluctance to invest in airport bird control is a lack of understanding of the true costs to the airlines in terms of direct damage to aircraft and in delays and cancellations. Previous estimates of the cost of bird strikes have concentrated only on measurable repair costs and have not attempted to assign costs to aircraft delays. My paper uses newly available data from major international airlines to provide the first estimate for the total cost of bird strikes to the world’s airline fleet. Much of the data are commercially confidential and sources cannot be quoted nor the accuracy of the data verified. The estimates also rely on information from a very small number of airlines to produce extrapolations for the worldwide costs of damage and delays. Although these are major international carriers, and as representative as possible of the world bird strike problem as a whole, the results should be interpreted with a suitable level of caution. A tentative and probably conservative estimate of US$1.2 billion per year in damage and delays is the outcome of this calculation. The costs of bird damage are evaluated relative to the ability of managers to pay for bird control programs and the derived benefits thereof. Reasons for the industry’s failure to invest further to reduce the costs of bird strikes are examined.