Action Needed to Stem Rising Hazard of Bird Strikes

Air Safety Week, August 14, 2000

"We don't want to have people dead on the ground to say we have a goose problem."

- Dr. James Cooper, Ph.D., Dept. of Fisheries & Wildlife, Univ. of Minnesota

BLOOMINGTON, Minn. - It may be better to deliberately kill a few birds than to have one or more birds accidentally kill an airplane.

This is the sobering choice that emerged from last week's second annual joint meeting here of the U.S. and Canada Bird Strike Committee. The success of wildlife conservation and the continuing growth of the airline industry have placed two growing populations, one of birds and the other of airplanes, on a collision course. In and around airports, birds and aircraft are fighting for airspace.

"We take the issue very seriously. Any time we introduce a proliferation of machines into nature, we're going to have a problem," observed Gene Peterson, chief safety officer for Northwest Airlines [NWA].

Demographics of Danger

Richard Dolbeer, head of the US/Canada bird strike committee, described the problem succinctly: "We have more birds in the sky. We have more airplanes in the sky, and we have more lawyers involved in litigation." In other words, not only is there a growing safety hazard, airlines and airport operators face greater exposure to legal action absent evidence of robust programs to minimize potential aircraft collisions with wildlife.

Numbers tell the tale. As Dolbeer pointed out, today's bird population is greater than in 1900. As examples:

* In the Great Lakes area, in 1972 there were only six or seven breeding pairs of double-breasted cormorants. In 1997, there were 100,000 breeding pairs.

* From 1966 to 1998, the red tailed hawk population in the U.S. doubled.

* The non-migratory Canada goose population in the U.S. has exploded, from about 250,000 birds in 1970 to an estimated 3 million today. Presently, the goose population is growing at an estimated rate of some 13 percent annually.

Jim Cooper, a bird management expert at the University of Minnesota, said the Canada goose represents "a success story in wildlife management and a population growth horror story."

"We've created refuges for Canada geese called cities," he added. As an example of the growing hazard geese pose to aircraft, Cooper pointed out that in 1966 some 50,000 Canada geese were counted on the so-called Mississippi flyway, their great migration route. In 1999, some 68,000 Canada geese were counted in the nearby twin cities area (Minneapolis/St. Paul) alone.

"Now we're seeing the same with snow geese," Cooper added.

Richard Parker tracks bird strikes for engine manufacturer Pratt & Whitney [UTX]. "We see bird ingestions rising in proportion to the Canada and snow goose populations," he said. "They fly in flocks, which means you can have ingestion in more than one engine."

Why are these goose populations growing? Cooper recalled Lewis and Clark's great exploration of the American hinterlands in the early 19th century. Only twice did their journals mention sightings of goose nests, and they were in trees. However, the explorers remarked in wonder at the huge number of buffaloes and wolves. The wolves preyed on the buffalo, but as Cooper noted, wolves are opportunistic feeders and "will never pass up a goose nest." Wolves, it seemed, not only culled the buffalo herds, they kept the goose population in check. A decline in the wolf population was a corollary effect of hunting the buffalo almost to extinction. In the often-unrecognized inter-relationships of the natural world, fewer wolves led to more geese.

More airplanes are filling the skies, too. Commercial air traffic will double, from 16 million aircraft movements in 1982 to an estimated 32 million movements in 2004.

More birds. More planes. Little wonder that the number of reported bird strikes has increased some 180 percent, from 1,700 reported strikes in 1990 to about 4,900 in 1999. In fact, it is estimated that some 80 percent of all bird strikes go unreported. For example, Northwest and United Airlines [UAL] respectively report about 300 bird strikes per year. But a recent internal study at United placed the number of bird strikes in 1999 at 1,300; some 40 percent of the foreign object damage (FOD) at United is due to bird strikes, according to this study. Because of the uncertainty about the real scope of the bird strike hazard, the National Transportation Safety Board (NTSB) would like to see a mandatory requirement to report bird strikes.

Conventional wisdom in the industry holds that bird strikes cost some $300 million per year in damages and lost revenues. John Allan, head of the United Kingdom's Birdstrike Avoidance Team, places the worldwide annual cost to the industry much higher, at $1.2 billion.

There also is a cost in human lives. The 21 killed April 20 when a twin turboprop was downed by a birdstrike in Central Africa brings the human toll to more than 100 since 1995. According to Capt. Paul Eschenfelder, director of airport safety and standards for the Air Line Pilots Association (ALPA), more people have died in airplane collisions with wildlife than have been killed by icing or encounters with volcanic ash. "Other than CFIT (controlled flight into terrain), wildlife is number one," he maintained.