MANEN W VAN, A POT, G OTTENS & M JONKER (2009) Successful breeding of Tengmalm's Owl Aegolius funereus in Drenthe in 2008. LIMOSA 82 (2): 49-58.

Large forests (500-2500 ha) in Drenthe, The Netherlands, were mainly planted in 1920-50 and are dominated by exotic conifers like Japanese Larch Larix leptolepus and Norway Spruce Picea abies. The resemblance to boreal forests and the presence of Black Woodpecker Dryocopus martius (excavating nesting holes) since about 1970 make these forests a potential breeding site for Teng - malm's Owl.
      On 23 February 2008, a singing Tengmalm's Owl was found in the forestry of Schoonloo, Drenthe by a team of birdwatchers during an organised search for the species. From that day onwards the area was inspected frequently and calling owls were mapped (Fig. 1). The male soon turned out to be paired and on 15 March a second male was detected, calling at a distance of 500 m from the first one. Also this male was accompanied by a female.
      On 5 May, in the second territory, a Tengmalm's owl peeked out of a hole in a Beech Fagus sylvatica made by a Black Woodpecker, after the observer scratched the bark. On 9 June the hole was inspected and two nearly grown young and two addled eggs were found. The young birds fledged between 18 and 20 June but both were found predated, presumably by a Northern Goshawk Accipiter gentilis, on 21 June. In the first territory a nest, also in Beech, was found on 18 June at 500 m from the other nest. It contained four young which were ringed on 8 July (Table 1). Three young survived and fledged between 14 and 19 July. One of the fledglings was found predated on 19 July near the nesting tree, and evening checks over the next weeks revealed no begging young. Nevertheless this constitutes the first successful breeding of the species for the Netherlands in well over 30 years.
      The first breeding event (which also constituted the first record of this species for the Netherlands) took place in 1971, when a freshly dead juvenile was found in Drenthe. During 1972-1979 up to nine territorial males were found in Drenthe on a yearly basis. This resulted in two documented breeding records in 1974 and 1977, which both failed in the egg stage. Singing males were again noted in Drenthe during 1985-1987, 1994 and 1999. Apart from these territorial birds the species is a vagrant in The Netherlands with only 11 additional accepted records (mostly from December-March) of birds that were found dead or moribund.

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