GULDEMOND JA: SOSA ROMERO MC & TERWAN P (1995) Meadow birds, water tables and nest protection: ten years of research on Lapwing Vanellus vanellus, Black-tailed Godwit Limosa limosa and Redshank Tringa totanus in a peat soil area. LIMOSA 68 (3): 89-96.

A lively debate is going on about the influence of water table lowering on size of breeding populations of meadow birds. The current opinion is that drainage has a negative effect on the number of breeding pairs. This could result from either a decrease in colonization due to habitat changes (vegetation structure, food availability), or from reduction of breeding success due to intensification of dairy farming (i.e., earlier mowing). Population trends of Lapwing, Black-tailed Godwit and Redshank were determined in the peat-soil area Waterland, The Netherlands, during 1982-91. The study area consists of grazed and mown grassland used for dairy farming. Several grassland areas have been drained in Waterland in the course of the study period. Mean water table lowering was 35 cm during the study period, and there was a trend for mowing to start earlier (fig. I). Meadow bird nests were actively protected in order to reduce losses caused by farming practices. We studied the effects on meadow bird breeding population size On the basis of the number of clutches found and hatched, we conclude that breeding population size of meadow birds either remained stable (Lapwing), decreased slightly (Black-tailed Godwit) or increased (Redshank) during 1982-91 (fig. 2). Nest density of the three species did not differ between fields where the water table remained high (0-40 cm below field level) and fields where the water table was lowered by c. 27 cm since 1982, resulting in a water table between 41 and 80 em below field level in 1991. However, nest density was by 30 to 50% lower in fields where the water table was lowered by 77 to 102 cm, resulting in a water table below 80 cm in 1991 (fig. 3). For the period 1987-91, we found no relationship between change in water table class of individual fields, and change of meadow bird nest density at the fields (fig. 4). This suggests that a moderate lowering of the water table in a peat-soil area does not necessarily result in a decrease of the number of breeding pairs, provided that meadow bird nest protection is practised. The effect of lowering of the water table on meadow bird population density appears not to be the result of decreased colonization, but rather of reduction of breeding success. Nest protection therefore is an important tool for conservation of meadow birds in areas with dairy farming. When farmers and conservationists join forces and practise nest protection, it will be to the benefit of meadow bird populations in non-protected areas ##### Northern Lapwing Vanellus vanellus Black-tailed Godwit Limosa limosa Common Redshank Tringa totanus

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