While birds, mammals and airplanes may seem to peacefully share the space at and around airports, their co-existence is burdened with extreme risk. In the case of a collision with an aircraft, a single animal has the potential to cause severe damage, leading in some cases to the loss of the aircraft, its crew and passengers.

If one were to assess the risk associated with wildlife strikes based only on the accident record of jet transport aircraft in the western world, it would be easy to conclude that related problems are negligible. And yet the closer examination of available statistics by industry professionals who are intimately involved in wildlife-hazard management provides a sobering assessment of the current wildlife-strike risk.

In this book we will demonstrate that the wildlife-strike risk is very real and demands serious consideration by the aviation industry, particularly considering the remarkable increase in the populations of some large flocking birds during the past few decades, as well as the associated increase in aircraft numbers and activity.

Aviation-industry professionals are acutely aware that the public has no tolerance for accidents involving large jet-transport aircraft. In spite of the industry’s impressive safety record, the fatality/injury ratio and fatality densities associated with aviation accidents continue to capture widespread attention. The public outcry, media focus, family outrage, and ongoing litigation that will inevitably result from a wildlifecaused jet-transport accident in the western world motivates many managers to do whatever is necessary to avoid the experience.

Generally speaking, aviation-industry professionals are highly motivated, innovative and technically oriented. They are accustomed to dealing with issues that, while often extremely complex, can for the most part be addressed by engineering solutions. Finding solutions to wildlife-associated hazards, however, also requires application of the natural sciences. Only when a proper balance is struck between these two disciplines will the industry myth be dispelled that wildlife hazards are an act of God.

We believe that the risk associated with wildlife hazards, while currently underrecognized, can be managed economically and effectively. We hope that you will apply the lessons of this book and improve the management of wildlife risks within your segment of the aviation industry.


A history of bird and mammal strikes

Bird strikes have been an issue since the earliest days of manned flight. In their diaries, the pioneering Wright brothers recorded what was likely the first strike following a 4,751-metre flight over cornfields near Dayton, Ohio, on September 7, 1905. In fact, the pilot twice encountered flocks of birds during four circuits of the area. (While the Wrights did not record the species struck, it’s likely Red-winged Blackbirds may have been involved; major pests during September in Ohio, these birds attack ripening corn in large flocks.)

The first recorded human fatality resulting from a bird strike occurred in 1912. Cal Rogers, the first man to fly across the United States, crashed into the ocean after a gull became jammed in his aircraft’s flight controls. Since then, bird strikes have become an increasingly serious problem in both civil and military aviation, with many thousands of strikes occurring every year.

Since 1912, available data shows that more than 223 people have been killed worldwide in at least 37 bird-strike related civil-aircraft accidents. In addition, a minimum of 63 civil aircraft have been lost as a result of bird-strike related accidents. In military aviation, the number of documented serious accidents since 1950 exceeds 353, including a minimum of 165 fatalities. Experts are convinced that bird-strike statistics are vastly under-reported, and that the true numbers of accidents and fatalities are much higher. There are many reasons for this under-reporting:

  • There are no consistent worldwide standards.
  • Wildlife-strike reporting is not mandatory.
  • Some countries are reluctant to publish such statistics out of concern for liability and negative public perception of flight safety.
  • In some parts of the world, information on serious accidents is lost for a variety of reasons, including a level of media attention lower than that we are accustomed to in the western world.

To highlight the unreliable nature of data associated with bird-strike accidents, consider the April 2000 crash of an Antanov AN-8 that collided with birds on takeoff from Pepa, Congo. Few details of this accident are available, despite the death of 21 people. In some regions of the world, neither the funds nor the expertise exist to permit proper investigations.


Accidents waiting to happen

The bird-strike problem is a global one. Although the types of aircraft and species of birds involved in strike incidents vary from region to region, the population of some bird species and the number of aircraft sharing the skies is increasing everyday—in every corner of the globe.

While birds can be struck in the air or on the ground—as an aircraft takes off or lands— virtually all collisions with mammals occur on the ground, with the exception of those with bats. The number of collisions between aircraft and mammals is not nearly as large as the number of bird strikes, but given the comparatively greater weight and size of mammals, the resulting damage from a mammal strike can be serious.


A flight-safety problem that’s here to stay

The risk that a multiple bird strike will result in the crash of a large airliner, while statistically low, is slowly rising and cannot be ruled out. The loss of life would be catastrophic.

Real economic losses are already mounting. Although difficult to estimate accurately, the total cost of wildlife-strike damage—according to the best available industry estimates—likely involves many millions of dollars a year for Canadian civil aviation alone.

Bird and mammal strikes will continue to be a safety issue for many reasons:

  • The number of aircraft and flight movements are increasing worldwide.
  • The populations of a number of high-hazard bird species are increasing.
  • The populations of some mammal species are on the rise.
  • Urban encroachment on airports forces birds to use the relatively safe airport environment and its associated arrival and departure paths as the only remaining open space.
  • Wildlife-management procedures at airports are unlikely to succeed in keeping the airport completely free of birds and mammals.
  • Detecting airborne birds in time to avoid a collision is often not feasible.


Wildlife-strike risks can be reduced

Wildlife biologists have recently become more influential at the decision-making level in the aviation industry. These experts have strenuously argued that wildlife strikes are, for the most part, not acts of God. Rather, such incidents are usually the results of careless management of either wildlife or habitat at and near airports, or are caused by inadequate timing, planning and execution of flight profiles.

There is not, nor will there ever likely be, a single solution to the wildlife-strike problem. However, this costly flight-safety dilemma is manageable to a certain extent. Through application of a system-safety approach and a coordinated effort by the aviation community, the number of fatal accidents and costly incidents can be minimized.

Careful use of state-of-the-art wildlife-management techniques and current technology to detect hazardous bird movements can provide timely information and warnings to flight crews. Enhanced bird- and mammal-impact protection of aircraft and engines can have a measurable effect on reducing the risk and associated costs— both human and financial—that bird and mammal strikes incur.


Sharing the Skies: A new look at the wildlife-strike problem

There is an abundance of literature, in many languages, dealing with the various aspects of collisions between aircraft and wildlife. This literature provides excellent sources of information but tends either to address limited aspects of the problem or concentrate on a solely biological or engineering solution. To date, no single industry publication has been written to provide a comprehensive overview of the wildlifehazard issue.

For many years, Transport Canada has raised industry awareness of this safety problem through education. The department was involved in writing Bird Hazards to Aircraft (Blokpoel, 1976) and has since produced the Wildlife Control Procedures Manual (Transport Canada, 1994). An Internet website ( has also been developed, along with a series of Wildlife Bulletins, posters and videos dealing with bird-strike problems at Canadian airports.

Transport Canada recognized recently the need to publish a new, practical, comprehensive and user-friendly guide to managing wildlife hazards, prompted by the following developments:

  • A recent analysis of bird- and mammal-strike statistics indicates much higher damage costs than previously estimated.
  • Several recent fatal accidents have involved large, military versions of civilian jet transport aircraft.
  • The recent population explosions of some high-hazard bird species.
  • The increasing complexity of managing wildlife populations due to concerns expressed by wildlife conservation groups.
  • The opportunity to include the latest available wildlife-strike research.
  • The evolution of Transport Canada’s role from operator, regulator and service provider to regulatory body.
  • Privatization of the Canadian civil-aviation system has resulted in private-sector operation of airports and the air-navigation system.

Sharing the Skies presents aviation professionals with relevant and comprehensive background information on the nature and magnitude of the wildlife-strike problem. The book also describes and recommends effective strategies to reduce the risk associated with wildlife strikes.

A valuable resource for all aviation professionals

Sharing the Skies is published by Transport Canada and is written primarily as a tool for aviation professionals within Canada and the U.S., where the majority of the world’s air-traffic activity takes place. However, the authors recognize that wildlife strikes occur worldwide. A great deal of excellent work has been done in Europe, Israel and other parts of the world, and we make reference to those efforts in various chapters. We trust this book will be of use and interest to a global audience.