Ethologische Forschungen an Grünflügelaras (Ara chloropterus Gray, 1859) im Tierpark Hagenbeck, Hamburg – In memoriam Dr. Ralf Wanker (1961–2011)

The Hamburgian ethologist Dr. Ralf Wanker (1961-2011) together with his students started an ethological research program on a group of up to 15 Green-winged Macaws (Ara chloropterus) at Tierpark Hagenbeck, Hamburg, in 1998. Up to his sudden death in 2011 he had supervised several academic studies on this group, the results of which have not been published yet. This paper gives short summaries of six of these studies, realized between 2001 and 2009. Main topics were the social and acoustic communication of the birds as well as the conflict management and conflict avoidance within the group. The results of these studies shed light on the potentials and difficulties of keeping big macaws in groups under zoo conditions.