On second thought, the one advantage which this does have over alternatives (like throwing a net to foul the props, or using a microwave canon to disable the el

On second thought, the one advantage which this does have over alternatives (like throwing a net to foul the props, or using a microwave canon to disable the electronics) is that the drone won't plummet into the crowd below. If you can rely on the assumption that a drone which loses control signal will hover in place or slowly descend (or some similar "safe" maneuver), you could combine the bird technique with a jamming device. The jamming device keeps the drone still just long enough for the bird to snatch it out of the air safely. Similarly, you could train the bird to expect the drone to start free-falling just moments before it arrives, such that the bird compensates and catches the drone in free-fall. You could then deploy the bird against a drone and use a focused microwave cannon to take out the drone's electronics just before the bird arrives.