Birds and aircraft must share the sky, but search the terms “bird” and “plane” together on Google, and you’ll see that the two don’t always get along.
There are bird strikes all over the world, resulting in emergency landings and damaged aircraft. The aviation industry spends a minimum of US$1.2 billion (888 million euros) per year on bird strike damage and delays, estimates John Allan, head of the national wildlife management center, which is part of the UK Animal Health and Veterinary Laboratories Agency.
Airports aren’t just hubs where cargo flies to its destination; they are wildlife habitats where birds and other animals thrive – and airports must manage birds in order to protect planes.
“The challenge is as we have clear zones on the approach and departure ends of our airport, as do all airports,” Steve Osmek, airport wildlife biologist at the Port of Seattle, says. “Frequently, if they are in urban areas like we are, it tends to be some of the last real good quality habitat for wildlife, including hazardous wildlife.”
The challenge at Seattle-Tacoma International Airport, which is operated by the Port of Seattle, and at every airport across the global is reducing the number of birds hanging out at the airport.
Statistics for bird strikes are murky. In 2012, there were 10,726 wildlife strikes in the U.S., the vast majority of which involved birds, according to the Federal Aviation Administration. The UK Civil Aviation Authority reported 2,215 bird strikes.
But reporting standards differ based on country, says Allan, former chairman of the International Bird Strike Committee and a specialist in bird strike prevention in York, England, for the past 25 years.
And that US$1.2 billion spent on bird strike damage and delays? That is Allan’s best calculation, but the number may well reach five times that amount.
David Gamper, director, safety and technical at Airports Council International, says ACI does not collect statistics on bird strikes, though the Montreal-based organization will start to gather statistics in 2014.
Protecting aircraft involves active management of the hazard, Gamper says.
“Not just taking measures on the day but also taking environmental measures to reduce the number of birds present on the airport, and particularly birds that present the greatest threat to aircraft,” he says. “Those tend to be, in general, flocking birds and larger birds. But it very much depends on the situation of the airport.”
Allan says airlines and airports must work together to keep bird strikes to a minimum.
“It’s actually one of the more interesting things about the way the industry is set up in that the airport is responsible for ensuring that these are safe operation environments, so it has to spend the money to do the bird control. But it’s the airline that actually benefits from reduced numbers of bird strikes because it has less damage, fewer delays and so on,” he says. “That’s always been one of the problems, is that disconnect between the people who have to spend the money to prevent bird strikes and the people who actually benefit from it.”
Allan says airlines are beginning to insist that airports seek advice to prevent bird strikes.
“One reasonably serious bird strike can swallow up an entire profit margin on a route for months at a time,” he says.
Gulls, Canadian geese, bigger birds and flocking starlings present the most risk at airports, Allan says.
“There are some very basic principles wherever you are, and you have to adapt them to your situation,” Allan says. “You are not going to do the same sorts of habitat management, for example, in the United Kingdom where it’s warm and wet relatively speaking. Grass grows all year round. Compare that with Saudi Arabia where you’re in the middle of a desert. There is no grass. You’re going to be doing different things.”
Allan says the basic principle is to determine what attracts birds to the airfield and either remove it or deny the birds access to it.
“In a good bird control program, controlling the attraction is 75 percent of the issue,” he says. “Twenty-five percent of the issue is then going in and scaring away what birds are left.”
Osmek seems to follow this advice when he takes steps to keep the birds away at Sea-Tac.
“First and foremost, and where I spend most of my time, is mitigating hazardous wildlife attractants on and near the airport,” Osmek says.
He makes sure that the airport has few open wetlands, and with the few it does have, the airport removes the open water by planting dense vegetation. That impedes waterfowl from landing.
Osmek has a different tactic for storm water ponds. The bottom of these has a plastic liner to prevent vegetation from growing and netting on top to keep birds out.
Sea-Tac uses the usual tactics to scare birds away: pyrotechnics, noise-making devices and a green laser light. But Sea-Tac, the first U.S. airport to employ a full-time wildlife biologist, still comes up with creative ways to combat bird strikes.
Osmek runs a remote control airboat with a fake coyote on the front to frighten birds in the open wetlands.
Raptors such as eagles do a lot of damage to aircraft, so Sea-Tac uses a Swedish goshawk trap that also has a texting feature. The trap works by having pigeons down below in a cage, protected from above by any raptor that will try to grab it. The raptor comes to a box above it, landing on a trigger device that closes the trap doors.
When a raptor is trapped, a text alerts the airport. The goshawk trap has been used around the world for years, but Sea-Tac added the texting feature in 2011.
The trapped birds ride on the airport buses for free, traveling to Northwestern Washington Forest to be released into the wild. Sea-Tac has moved 500 birds with its trap, Osmek says.
“That, along with the texting trap, has really revolutionized the way we move birds out of here,” he says.
Singapore Changi Airport has a 12-member wildlife management team that conducts daily patrols to monitor the movements of birds and other animals. Mynas, sparrows, egrets, crows and kites are common in Singapore.
“With some 600 hectares of turf, the presence of water bodies and its close proximity to wooded areas and the coast, Changi Airport is a natural sanctuary to a variety of birds and other forms of wildlife,” a Changi Airport Group spokesperson says. “All bird sightings are recorded to identify hotspots, which will be even more closely monitored.”
Changi broadcasts bird distress calls and puts anti-perching devices on railings nears the runways and taxiways
“At the airside, besides having covered dustbins that prevent birds from foraging for food, airport personnel are forbidden from consuming food and beverages,” the spokesperson says. “No fruit-bearing trees or plants that attract animals are planted within the airport as well.”
Managing bird strikes is a never-ending job for the many airports across the world.
Allan says novel solutions to reduce bird numbers on the airfield are always in development.
“It’s a bit like developing the better mousetrap, as it were,” he says. “There will always be a problem, but we’ll just get more and more sophisticated about how we deal with it.”
Airports must actively reduce the threat of bird strikes, but banishing the birds altogether is not an option, Gamper of ACI says.
“You’ll never get rid of them, and it’s not only a possibility – it’s not desirable for environmental and ethical reasons,” he says. “What you have to do is try and modify the animal’s behavior and try and get them out of the critical safety zones where the aircraft are operating.”
Image caption: A wildlife management team member at Singapore Changi Airport watches for birds.