NIJLAND F (2007) A successful year for reproduction of Dutch grassland waders in 2006. LIMOSA 80 (3): 96-102.

A combination of cold weather in March and early April 2006 followed by a rainy period of nearly three weeks from mid-May (fig. 1) led to an unusual situation in agricultural grasslands in the province of Friesland, but also elsewhere in The Netherlands. In the first two weeks of May, the usual peak period of the first cut of conventionally farmed meadows, most grass was not yet tall enough to be harvested. During the second week ofMay some fields were cut, but then the rains precluded further mowing until the first week in June, leading to a far greater availability of unmown grasslands in the chick period of meadow birds than is nowadays usual (fig. 2). Moreover, the slowly-grown grass had a varied structure, with more and less dense areas.
      Weidevogelmeetnet Friesland has since 10 years operated a census program in which volunteers map meadow bird territories in c. 65 plots per year throughout the province, and also record alarming birds indicating the presence of chicks in the greater part of these plots to obtain an indicator of reproductive success (gross territorial success GTS), in particular for Black tailed Godwit Limosa limosa and Common Redshank Tringa totanus. Comparison of data from 2006 with those from 1997-2005 shows that both species bred significantly more successfully in 2006 than in the preceding years (figs. 3, 4).This applied to all three management regimes distinguished, but in godwits more strongly so in conventionally farmed areas than in nature reserves, where mowing is postponed in other years as well. For the first time in at least ten years, reproductive success of godwits may have been sufficiently high to compensate adult mortality in many sites. The 'natural experiment' created by the unusual weather conditions in 2006 showed that grasslandmowing schedules are a key factor that can (in 2006 combined with a varied sward structure) overrule other factors affecting the survival of grassland wader chicks.

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