De teloorgang van een sperwerbroedsel Accipiter nisus

Between 17 and 20 June 2001, five nestling Eurasian Sparrowhawks, a male and four females (21 -22 days old, based on measurements taken 6 days later), were found on the ground in a city park of Rotterdam, where also a dead Sparrowhawk was recorded (age not known). These birds were transported to a rehabilitation centre, but all young died within two weeks. By that time, the birds were still unable to fly. Post- mortem research was performed on 3 of the 5 Sparrowhawks (a male, two females), at the Pathological Laboratory of the Faculty of Veterinary Sciences of the State University of Utrecht, by Dr. G.M. Dorrestein. All three birds showed signs of serious undernourishment, notably visible in the poorly developed musculature. In one female, the left pectoral muscle was even more poorly developed than the right one, in line with an asymmetric growth of the carpal bones. This latter condition also explained why this bird was unable to stand properly, as another female from the same nest. The cause of this malformation was probably lack of (high quality) food. The second female was, apart from being undernourished, infected with Aspergillus fumigatus. The males was in better condition than his siblings, but subcutaneous fat was lacking. The male had a dry infection of an atrium, presumably the direct cause of death. All three birds showed modest numbers of Esecheria coli in the rectum, one female also some streptococci Streptococcus spp. It is thought that all nestlings had suffered serious food shortage, presumably following the death of one of the parents, which in its turn affected the immune system negatively, resulting in poor growth, malformation and infection with bacteria and fungi.