New tactics to avoid animals being killed on runways by aircraft could be applied internationally and save airlines millions of euro in aeroplane damage, researchers believe.
Studying the behaviour of hares at Dublin Airport, the team used motion-activated camera traps to collect activity data on hares inhabiting the airfield at the airport and found hares were more likely to be struck at times of lower aircraft activity, namely sunrise and midnight.
The team, led by Samantha Ball, an Irish Research Council scholar at the School of Biological, Earth and Environmental Sciences (BEES) at University College Cork, began looking at Dublin Airport after conducting earlier research on wildlife-aircraft collisions internationally.
That research found wildlife-aircraft collisions with all sorts of mammals from voles to giraffes are increasing annually by up to 68 per cent in some countries, and in the US such collisions have caused damage to aircraft totalling more than $103 million over a 30-year period.
Ms Ball and her fellow researchers, Anthony Caravaggi and Fidelma Butler published their findings in the journal Remote Sensing in Ecology and Conservation.
Ms Ball said they began by identifying two distinct periods of increased strike risk — around sunrise and approaching midnight.
“Of course, with varying day length throughout the year in Ireland, there is some seasonal variation here. We also found that hare strike times at the airfield were closely associated with the times of day when hares were most active at the airfield but when aircraft movements were relatively low.
“This tells us that we can focus strike prevention efforts — such as scaring tactics and runway patrols — directly on to the hare population themselves as opposed to facing the near-impossible task of altering aircraft activity, to reduce hare strike events.
“This work has allowed us to identify periods throughout the day, and year, when strike risk with hares may be higher, indicating when strike prevention efforts can be increased to deter hares from the active runway.
“The research can also be applied to other airfields, as although we focus here on the Irish hare at Dublin Airport, this method can be used to identify periods of increased strike risk with ground-dwelling species of concern worldwide, such as deer and large carnivore species,” she said.
While the animals most likely to cause runway strikes in Ireland were hares, rabbits, foxes, badgers, hedgehogs and bats, the experience internationally was that all sorts of mammals including giraffes, could be involved, she explained.
“Internationally, a huge number of animals feature — everything from voles to kangaroos to giraffes — the case involving a giraffe happened in Botswana and involved a light aircraft, which are more prone to damage, and it actually turned out to be a fatal collision” she said.
While aircraft colliding with small animals such as rabbits or hedgehogs generally don’t cause any great damage to aircraft, they can lead to other larger carnivores coming on to a runway to feed on the dead animal. “The extent of the damage to an aeroplane depends on the kinetic energy involved which depends on the speed of the aircraft and the size and weight of the species that is hit — the kinetic energy in a rabbit strike is quite low for example and they aren’t struck all that often at Dublin Airport
“There is only one recorded case at Dublin of a rabbit strike but there is a risk if something like a rabbit is struck, it will attract another species to the location of a strike — there was a case some years ago of a hedgehog being struck and it caused a lot of damage because gulls were attracted to the site.”