KENAI, Alaska (AP) — From 100 feet in the air, Kenai National Wildlife Refuge ecologist Mark Laker can find a piece of smoldering ash or a tiny spot of excess heat that could spark a wildfire.

Laker pilots two 3DR surveillance drones — one of which is equipped with heat-sensing technology — that the refuge has been using over the last year to monitor wild areas.

On a recent Thursday, Laker piloted the drone over a 3.5-acre section of the refuge near Funny River Road where a hazardous fuel reduction project was taking place. As fire officials monitored small piles of burning wood and ash, Laker...