To find out, how many resting cranes can be found in Germany, they have to be counted simultaneously. The German Crane Working Group has established a network of crane counters in the last years. The results of these counts are collected and analysed at the NABU-Crane Centre annually.
At fixed dates during autumn migration and in winter, the cranes are counted simultaneously at all relevant roost sites. The counts are mainly conducted by many volunteer crane friends during the morning or evening flights from or to the crane roosts. The results allow estimates of the total population of resting and wintering cranes in Germany.
Based on these counts the timing of the autumn migration, maximum numbers, as well as changes in the resting population can be determined. The long-term dataset from the region Darß-Zingst Bodden chain and island Rügen for instance shows a long-term increase, but more or less stable maximum numbers in recent years.
Understanding the cranes
Apart from simultaneous counts cranes that take a rest in the region of Darß-Zingst-Bodden chain and island Rügen, are also regularly mapped. During special field counts important information about feeding behavior, habitat and site use, flock size composition and juvenile percentages are collected.