Individual recognition, territorial and partnership fidelity of cranes evaluated by sonography
Such monitoring is - until now - only feasible when banding birds. However, banding requires specific know how, official authorisation and is usually limited by the fact, that banding is easier with catching young unfledged birds.
This results - even in broader programs - in that only in a few cases by luck 2 banded birds are mating. Therefore, there are also attempts to catch adult paired cranes (by anesthesizing them) which is quite complicate and not free from risks.
Both for behaviour research, as for endangered species conservation and general nature protection reasons, an identification method without disturbing the birds or risking any losses, hence from distance, and a method which can be practised without huge financial investments, by individuals and by teams, is desirable.