Ruigpootuil Aegolius funereus geslagen door Havik Accipiter gentilis in Drents bos

A freshly depredated Tengmalm’s Owl was found in the Forestry of Hooghalen in the province of Drenthe on 12 October 2002. The plucking site (open forest floor underneath a mixed stand of Picea abies/sitchensis), the nature of the plucking (feathers pulled, sometimes several primaries pulled simultaneously) and the slender stripe of uric acid next to the plucking indicated that a male Northern Goshawk was most likely the responsible predator. Primaries, secondaries, rectrices nor coverts showed any variation in abrasion or colour, suggesting that the bird had finished its first moult but was still in its first calender-year. Tengmalm’s Owls are rare birds in The Netherlands, with most observations in the province of Drenthe where irregular cases of breeding have been recorded in the 1970s. Surprisingly, the Tengmalm’s Owl was the only Goshawk plucking found during 4 hours of fieldwork in 250 ha of woodland. The Forestry of Flooghalen covers 1400 ha, in which 8-9 pairs of Goshawks have been nesting in the last few years. It is surmised that Northern Goshawks – at least in Drenthe outside the breeding season – mostly hunt in farmland away from woodland, only returning there to spend the night in their territory. Return and departure overlap with the hunting activities of nocturnal species, probably explaining the disproportionally large impact of Goshawks on Tawny Owl Strix aluco and Long-eared Owl Asia otus in forestries in Drenthe (cf van Manen & Bijlsma 2000), as well as the poor chances of survival of the occasional Tengmalm’s Owl.