OOSTERVELD E, HEIKOOP L, WYMENGA E, SIKKEMA M & BEEMSTER N (2017) Breeding birds of the hedgerow landscape of Noardlike Fryske Wâlden, present and in the past. LIMOSA 90 (2): 60-71.

The typical cultural-historic hedgerow landscape of Noardlike Fryske Wâlden (NFW, near Drachten) is characterized by welldeveloped banked and Alder (Alnus glutinosa) hedges. This paper describes its breeding bird community as studied in 2012, changes therein since surveys made 30 years ago, and differences between banked and Alder hedges. Breeding birds were monitored by territory mapping in six plots and along 100 transects.
30 species of breeding birds were identified, of which 15 can be characterized as woodland species and 15 as shrub species. Transect counts revealed that shrub birds were 2 times as abundant as woodland birds, suggesting that, overall, hedges more closely represent scrub- than woodland habitat. This is the result of management of coppicing hedges every 20-25 years due to which a shrub habitat prevails. Densities of woodland birds were two times higher in banked hedges than in Alder hedges (when one plot of Alder hedges with exceptional management was excluded), underlining the more woodland-like character of banked hedges. Shrub birds were equally abundant in banked and Alder hedges. A notable exception is the Icterine Warbler Hippolais icterina which was 6.5 times more abundant in Alder than banked hedges.
Between 1989 and 2012 woodland birds decreased in Alder hedges by 50%, but increased by 50% in banked hedges, which possibly is related to a more intensive coppicing of Alder hedges whereas a denser and more diverse vegetation is maintained in banked hedges. In neither hedge type there was a change over time in the abundance of shrub species, nor in the total number of breeding birds. However, changes were noted for individual species. For some species changing wintering conditions in the Sahel may have influenced population change. However, for other African migrants local breeding conditions seem more important.
For seven species, Lesser Whitethroat Sylvia curruca, Common Redstart Phoenicurus phoenicurus, Common Whitethroat Sylvia communis, Mistle Thrush Turdus viscivorus, Garden Warbler Sylvia borin, Icterine Warbler and Song Thrush Turdus philomelos, the study area hosted high densities from a national perspective, suggesting the banked and Alder hedges to be preferred breeding habitat.

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