Military surveillance aircraft scoured the battlefield -- from the lowest-flying aircraft such as the Army's Hunter and the Marines' Pioneer, to the Predator, to the higher-flying Global Hawk and U-2 -- and on up to the information-gathering satellites.
Dr Webb's model shows that, over a 200-year period, average predator populations during hypothetical outbreaks of 14- and 15-year cicadas would be up to 2% higher than during outbreaks of 13- and 17-year cicadas.