Some Bears View the Friendly Skies

Environmental & Science Education
Edward Hessler

By dalliedee (http://www.flickr.com/photos/dalliedee/2993576282/)
[CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)],
via Wikimedia Commons

On August 13, I heard an interview by Dan Gunderson (Minnesota Public Radio) with bear researcher Mark Ditmer. Ditmer has been tracking radio-collared bears for years in northwest Minnesota. He has found no evidence that the bears have been bothered by it (based on heart-rate data).

However, when Ditmer used drones to monitor bear behavior (video camera), the bears showed  noticeable changes. Their heart rates spiked dropping only when the drones left the area. The heart rate of one bear, a mother with cubs, went from 41 heartbeats/minute to 162 heartbeats/minute. dropping only when the drones left the area. One bear ran away, moving faster than it ever had. Another bear changed its home range, moving about 7.5 km (and into another bear's home range). These bears were quite familiar with the noise of machinery from motor vehicles and farm equipment.

It is a small study--4 bears and 17 flights (at a height of about 20 m) but these findings certainly indicate the need for additional research since drones are increasingly used in conservation biology to study and monitor ecosystems. 

Gunderson's interview may be heard here. Additionally, these findings have been published in Current Biology.