After two bad seasons in 2013 and 2014, we accompanied this year two experienced ornithologists who controlled nestboxes of Tengmalm’s Owl (Aegolius funereus) in a forest of the Hunsrück in Rhineland-Palatinate. Because of the good food supply this year, the Tengmalm’s owl is likely to experience a better breeding season. This nocturne species has a body height of only 24-26 cm and it primarily subsists on small rodents such as mice. Its habitat consists of low mountain ranges between 450 m and 800 m above sea-level. The Tengmalm’s owl mainly prefers coniferous forests mixed with leaf trees including old nesting holes of the Black Woodpecker. Unfortunately, the brood of the Tengmalm’s owl is threatened by martens which climb up trees and eat their clutches.
Depending on the weather conditions, the females generally start breeding in April. A few chicks had hatched already when the ringer checked the nestboxes. In this ringing session only the females were ringed. A recapture of a female or a nest-ringed young owl is rare but there are already a few recaptures of Tengmalm’s owl in Belgium. They hatched and were ringed in the region Eifel, which shows that this owl species migrates between different low mountain ranges.