At dusk, the cranes fly out onto Lake Hornborgasjön to sleep. They often fly in small groups. This is the best time to count how many they are.

The crane counters define an imaginary line across the landscape and, using binoculars, count cranes that cross over this line. 

Several counters cooperate. Counting cranes requires that you are both attentive and thorough. The task is performed by experienced birdwatchers from the Lake Hornborga field station.