Artikel-Suche

Horch, P. & O. Holzgang

Hecken für Heckenbrüter: Erkenntnisse aus den drei Inventaren 1979, 1988 und 1999 im Kanton Thurgau.

2006

103

39–56

Key words
(von 1994 bis 2006 vergeben)

Hedgerow history, hedgerow structure, breeding birds, bird – habitat association, conservation management

Hecke, Niederhecke, Hochhecke, Baumhecke, Feldgehölz, Strukturenvielfalt, Krautsaum, Alter, Heckenpflege, Brutvogel, Besiedlung, Bestandesentwicklung

Schlagwort_Vogelart
(wissenschaftlich)

Sylvia communis, Sylvia borin, Sylvia atricapilla, Lanius collurio, Emberiza citrinella

Schlagwort_Vogelart
(deutsch)

Dorngrasmücke, Gartengrasmücke, Mönchsgrasmücke, Neuntöter, Goldammer

Schweiz, Thurgau

deutsch

Abhandlung

Hedgerows for breeding birds: comparative results from three surveys in the canton of Thurgau in 1979, 1988 and 1999 – Hedgerows are ecologically important habitats in Swiss farmland. They are therefore favoured by campaigns of nature and bird protection organizations and by government subsidies. To test for effects of these initiatives on hedgerow management and conservation, we documented, in the Canton of Thurgau as a case study, changes in the status of hedgerows over 20 years. We investigated which hedgerow characteristics are favourable for bird species typically breeding in hedgerows. Within the study area of 110 km2, hedges covered 34 ha and this did not change between the three inventories. About 13–14 % of hedges were cleared, but a similar amount of new hedges were planted. Due to inadequate management, the proportion of low-standing hedges dominated by bushes decreased from 23.3 % to 8.7 % between 1988 and 1999. Within the same time period tall hedges increased from 45.8 % to 62.4 %. Only about half the low and tall hedges, one in four copses, and one in six hedges with tall trees had at least 25 % thorny shrubs. Less than half of the hedges were bordered by a herbaceous strip. In 1999, Blackcap Sylvia atricapilla (240 breeding pairs) and Yellowhammer Emberiza citrinella (257) were most numerous and widespread, followed by Garden Warbler S. borin (66), Red-backed Shrike Lanius collurio (47) and Common Whitethroat S. communis (9). The probability of the presence of breeding birds in a hedge increased with increasing (1) hedge length for Yellowhammer, Red-backed Shrike and Garden Warbler, (2) width of the herbaceous strips for Blackcap, Garden Warbler and Yellowhammer, (3) percentage of thorny shrubs for Yellowhammer and Red-backed Shrike, and (4) hedge density for Yellowhammer. In conclusion we suggest the following management strategies to prevent a reduction in hedge number and to increase hedge quality: Conservation of old hedges, planting of new hedges, selective pruning to favour thorny shrubs, sowing and tolerating herbaceous strips along hedgerows.