Alaskan caribou and ptarmigan migrations recorded

A ladder of 14 automated cameras has for the first time recorded the northward springtime migrations of caribou and ptarmigan in the foothills of the Brooks Range, Alaska. Some 40,000 images allowed researchers to estimate the speed of the animals’ movement and their behavior en route. The authors created “animations” from photographs taken every 15 minutes. Their approach, which minimizes disturbance to the animals, could be used to elucidate factors affecting migrations of other species.