Hear the Buzz: Scientists Use Microphone, iPad Minis to Track Pollinating Bees

Researchers at the Webster University have developed a new method of tracking bee activity and pollination services that is a lot cheaper than any methods currently used in US farms.

The new method, described in a paper published in the journal PLOS ONE, utilizes microphones placed in strategic locations and a computer algorithm that can distinguished the number of bees based on their "buzzing" sound.

"We used inexpensive sound equipment to monitor for buzzing sounds created by bees as they fly. We then developed a computer algorithm that rapidly identifies and quantifies bee flight activity," said Nicole Miller-Struttmann, a biology professor at Webster University and lead author of the study, in a press release. "We believe that our method could be a much more cost and time efficient method for monitoring bee activity."

To test the effectiveness of their acoustic survey technique, the researchers strategically placed microphones and iPad minis in three different alpine meadows on Pennsylvania Mountain in Colorado. The survey areas were also visually recorded at the same time. Using a computer algorithm, the researchers tried to determine how many bees were in the area based on their buzzing sounds. They then compared the number they got from computer algorithm with the number of bees visually recorded.

Interestingly, the number of bees extrapolated from the acoustic survey was remarkably accurate and highly correlated with the number of bees counted in the visual recording.

In addition to accurately predicting the number of bees based on their buzzing, the acoustic survey technique were also able to distinguished bees that were only flying near the recording devices and bees that were actually pollinating. The researchers observed this during the second phase of their tests, in which they set up two different plants that bees normally pollinate. One of the plants was normal, while the other one was able to attract bees but can't be pollinated. Their new method successfully predicted which of the plant would set fruit and which would not.

The researchers noted that their new acoustic survey technique was not only inexpensive, but also nimble and suitable in remote locations.