The researcher recorded sounds produced by bees in five healthy hives in two Switzerland locations between February and June 2009. The study recorded the bees' sounds with active mobile phones in the hive. Two mobile handsets (900MHz GSM) were chosen at random.

The bees were also recorded during their normal activities, both with and without inactive mobile phones.

With the active devices, the first handset was triggered to call the second phone in the hive. A connection was made after 5 to 10 seconds of ringing.

Sound analyst shows the bees weren't disturbed by inactive or standby mobile phones. However, active cellphones confused the bees, creating "worker piping," or a signal to leave the hive.

The findings suggest that "the behavior of the bees remained perturbed for up to 12 hours after the end of the prolonged mobile phone communication," Favre writes. "This observation means that honeybees are sensitive to pulsed electromagnetic fields generated by the mobile telephones."