A verstile digital scarecrow promises to put a virtual cat among the pigeons. Birds soon get used to conventional scarecrows, and though simulated gunshots are effective, they are too loud. Now Bramley and Wellesley, a company based in Gloucester, UK, and Phoenix Agritech of Canada are all set to patent their invention: a solid-state digital recorder that stores birds' distress calls, predators' cries and the flapping of frightened birds taking flight. An amplifier linked to weatherproof loudspeakers intermittently generates the sounds. To people, they sound like real wildlife, not merely noise.