Although used primarily on the battlefield, drone technology is now proving beneficial to those looking to study the natural world. Biologists are supplementing their traditional flyovers, used for species counts, with new unmanned aerial devices that are much less intrusive and therefore less likely to disturb and frighten animals.

In Colorado, staffers from the U.S. Fish and Wildlife Service and the U.S. Geological Society are using a small drone called the Raven to explore the landscape and get a bird’s-eye view of the wildlife found therein:

Thermal image
A thermal image of roosting sandhill cranes.

In 2010, when researchers first tried out the Raven, no one knew what to expect; there were even worries that the birds might fly into the drone. While that did not happen, the cranes promptly scattered, perhaps mistaking it for a predatory eagle.

But then the scientists changed their approach. Sandhill cranes settle in the wetlands each evening and rarely move until morning, making them an easy target for a drone with a thermal imaging camera.

Video of the birds appeared as “a bunch of rice grains on a piece of paper, a dark piece of paper,” Mr. Dubovsky said. A complete count, which was conducted in an evening, proved to be as accurate as manned flight counts.