Monday, 18 August 2014

Airports are waging a war against birdlife

Here is some additional information, with videos, to accompany my latest article for The Ecologist, about collisions between aircraft and birds (bird strikes). Since a serious air accident was narrowly averted in New York on 15 January 2009, when the pilot landed a plane in the Hudson River after geese were sucked into both engines on departure from La Guardia Airport, awareness of the risk to air safety has been heightened. The video below shows the moments immediately after it landed in the river, note the remarkable speed of the evacuation as the plane filled with water.

Yet for all the furore over the problem of bird strikes the fate of birds is rarely mentioned. Many thousands are killed every year, when they are sucked into planes' engines and leave blood smeared dents when they hit the nose, wings or fuselage of an aircraft. Birds can also be injured and killed by the jet blast from aircraft, as at Tribhuvan Airport in Kathmandu, where the carcasses of two black kites and a spotted owl were discovered in March. These are just two of the 39 species of birds flying around the airport, at which there were 22 bird strikes in 2013 alone, and a fatal incident in 2012. Nineteen people were killed when a bird strike caused engine failure on a plane departing for the Mount Everest region. There have been many instances of large birds crashing through the windshield of small aircraft, splattering the pilots with blood. This harrowing video shows the moment when a Canada goose crashes through the windshield of a Cessna plane shortly after take-off from a small airfield in Illinois. Fortunately the pilot made a safe emergency landing and he and the co-pilot were unharmed.

Airports around the world have stepped up efforts to keep birds away from planes, deploying a bewildering array of methods: habitat management to make vegetation and water bodies unattractive to birds, and deterrence programmes such as loud noises, lasers and predatory falcons trained to frighten them away. But when these methods fail, or are inadequately implemented, airports frequently resort to culling birds. In the aftermath of the 'Hudson miracle' geese are culled over a wide radius around New York's main airports. The geese are shot or gassed. Another approach, preferred by many bird advocacy groups, is to coat goose eggs with vegetable oil to stop them hatching, undertaken at many airports including Winnipeg and Vancouver.

A non-lethal bird control method is to trap and relocate them. But this is only used for small bird populations, typically rare species which have been afforded legal protection. Since 2001, Sea-Tac Airport has successfully trapped and relocated 400 young raptors to an appropriate habitat in northern Washington. Boston Logan Airport traps and relocated snowy owls, and New Yorks's main airports were persuaded to adopt this approach in the light of a campaign against an announcement that wildlife officials would begin shooting snowy owls, after three bird strikes involving this species.

Another method used by some airports to kill birds is poisoning; An employee at New Plymouth Airport in New Zealand was appalled when he discovered that corn chips laced with poison were being laid out to kill birds considered a risk to planes, including sparrows. Video evidence of birds being poisoned emerged recently, when members of staff at Bush Intercontinental Airport in Houston witnessed the effects of United Airlines' poisoning pigeons and great-tailed grackles, in cooperation with Houston Airport System. Birds are shown suffered convulsions and it took up to an hour for them to die. The poisoning at Bush Airport was not a one-off, it takes place on an annual basis.

Smaller birds can also endanger flights. The video below was taken at Manchester Airport in 2007, at the start you can see a bird, a crow, being sucked into the engine. The plane made a safe landing but it appears that the airport began to take a more hostile approach to birdlife. In 2009 Manchester Airport informed that National Trust of its intention to shoot 800 rooks nesting in nearby woodlands, but announced a reprieve in response to a petition from local residents.

In May, the RSPB (Royal Society for the Protection of Birds) made an unsuccessful attempt to stop BAE Systems culling 1,100 black-backed gulls on the Ribble estuary, on the north west cost of England, in order to allay safety fears at nearby Warton Aerodrome. A judge ruled against an appeal, permission to kill the birds, almost one-fifth of the breeding population, was granted in addition to existing consents to cull 200 pairs of the same species of gull and 500 pairs of herring gulls. UK military airfields’ attitude to birds may harden further in the light of investigators’ confirmation that a fatal US Air Force helicopter accident on 7th January 2014 was due to a multiple bird strike. The helicopter crashed into saltmarshes in Norfolk, killing all four crew members. At least three geese crashed through the windscreen and another struck the nose of the plane.

New habitat management and deterrence methods only promise partial solutions to bird strikes. A system using low-frequency sounds, below the range of human hearing, to deter birds, has proved effective in tests. Hopefully,this will prove effective within airport sites, but it is unlikely to be feasible over the far larger areas where birds pose a risk to aircraft, on the take-off and landing flightpaths. 3-D printed robotic replicas of birds of prey - eagles and falcons - to frighten away target species. Again, this will only be effective in the immediate vicinity of runways.

It is clear that new airports must not be located near major bird habitats and migratory routes. Devastation of birdlife is a key factor in vigorous opposition to proposals for a new airport in London's Thames Estuary and on forested land to the north of Istanbul, where construction has commenced and a recent protest was met by riot police. In other instances, sanity has prevailed. The Georgian government has abandoned plans for an airport on marshlands in Poti and, construction of an airport in Nakuru, Kenya, has been stalled in recognition of the risk to air safety and birdlife including storks, pelicans and flamingos, as shown in the video below.

Birds do pose a risk to air safety, but, as explained in the article, the war that is being waged against them by airports is an over-reaction. The vast majority of stricken planes land safely and only a small proportion of serious air accidents are due to bird strikes. Airports should make every effort to keep birds away through habitat modification and deterrence, before resorting to culling, and more air accidents can be prevented by focussing on programmes to address the mechanical failures and human errors which lead to a far greater number of accidents and fatalities.

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