Its an issue bought to the fore by the now famous Sully Sullenberger birdstrike, admittedly that was off airport but more than one aircraft has ingested a bird into an engine at take off and had to deal rapidly with the consequences. BCU, bird control units exist at every airport. Normally playing bird distress calls through loudspeakers mounted to vehicles or firing exploding shot and letting off flares. One day soon maybe a small UAV will be in the toolkit as well."
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