France, Nov. 16 -- Armed with thermal-imaging binoculars, beekeepers in Alsace have taken to tracking insects with forensic zeal.

Their target is the Asian hornet, an invasive predator whose numbers have surged across the region over the past two years, wreaking havoc on local bee populations.

"For me, nest-hunting has become part of the job. If I want to keep beekeeping, I don't have a choice," says Mathieu Diffort, who runs around 100 hives in the rural Sundgau, near the Swiss border.

Diffort and his business partner, Philippe Sieffert of theApi&Cobee and enviromantal protection company, spend much of their season in the painstaking business of locating and destroying hornet nests.

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