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1. Intensification of agricultural use of grassland habitats has been linked to the declines of many farmland bird species, several of whom have been in decline for multiple decades despite agri-environmental schemes. In the Netherlands, where most grasslands have been transformed into well-drained monocultures managed for maximal dairy production, schemes that aim to protect nests from agricultural activities are the most popular. The cause of the failure of these schemes, however, seems poor recruitment of farmland birds. 2. Using the black-tailed godwit Limosa limosa limosa as our model species, we tested the hypothesis underlying the most popular agri-environmental schemes that there are no differences in condition at hatch, growth, and apparent survival rates between chicks raised on monocultures compared with chicks from herb-rich meadows with high water tables, often managed, for the sake of grassland birds, in traditional ways. We also compare the growth rates from both habitat types with those of chicks from dairy farmland from 1976 to 1985, a time when population declines of godwits first became visible. 3. Hatchling mass did not differ between chicks from herb-rich meadows and grassland monocultures, but chicks hatched on monocultures were on average 14-16% lighter at fledg-ing, and had 4% smaller bills than chicks hatched on herb-rich meadows. The growth rates of female chicks hatched on herb-rich meadows were similar to those of chicks measured from 1976 to 1985. Males fledged lighter and smaller than females. 4. Apparent survival during the first year of life for chicks hatched on herb-rich meadows was 2Á5 times higher than that of chicks hatched on grassland monocultures. The apparent survival on herb-rich meadows seems sufficient for a stable population. 5. Synthesis and applications: We found striking differences between chicks hatched on modern grassland monocultures and herb-rich meadows. That chicks hatched on monocultures had lower growth and survival rates than chicks on meadows indicates that these chicks suffer a higher risk of starvation and/or predation. These findings imply that the most often applied agri-environmental schemes (i.e. payments per clutch found and postponed mowing), are not effective. Instead, these schemes could even encourage maladaptive habitat choice. Conservation efforts should thus focus on the provision of herb-rich meadows with high groundwater tables.

When early breeding is advantageous, migrants underway to the breeding areas may be time stressed. The timing of sequential events such as migration and breeding is expected to be correlated because of a ''domino effect'', and would be of particular biological importance if timings are repeatable within individuals between years. We studied a colour-marked population of Black-tailed Godwits Limosa l. limosa both on staging areas in Portugal and on breeding areas in The Netherlands. For each individual, we measured the timing of the staging period, the arrival date on the breeding area and the egg laying date. We measured average egg volume as a measure of reproductive investment. The date of departure from the staging areas, the arrival date on the breeding areas, and the egg laying date were repeatable among years in individual Black-tailed Godwits. The arrival dates of paired males and females and the average annual male and female arrival dates were correlated. The dates of departure from Portugal, arrival in The Netherlands, and egg laying were not correlated. Earlier clutches had larger eggs than late clutches. If the length of the individually available pre-laying period is accounted for, early arriving birds spent more time on the breeding grounds before laying than late arriving birds. The repeatability of the itineraries and the correlation between arrival timing of males and females are consistent with observations in other migrants. Despite evidence for early breeding being advantageous, we found no evidence of a ''domino effect''.

Summary1. Extreme weather events have the potential to alter both short-and long-term population dynamics as well as community-and ecosystem-level function. Such events are rare and stochastic, making it difficult to fully document how organisms respond to them and predict the repercussions of similar events in the future. 2. To improve our understanding of the mechanisms by which short-term events can incur long-term consequences, we documented the behavioural responses and fitness consequences for a long-distance migratory bird, the continental black-tailed godwit Limosa limosa limosa, resulting from a spring snowstorm and three-week period of record low temperatures. 3. The event caused measurable responses at three spatial scales -continental, regional and local -including migratory delays (+19 days), reverse migrations (>90 km), elevated metabolic costs (+8Á8% maintenance metabolic rate) and increased foraging rates (+37%). 4. There were few long-term fitness consequences, however, and subsequent breeding seasons instead witnessed high levels of reproductive success and little evidence of carry-over effects. 5. This suggests that populations with continued access to food, behavioural flexibility and time to dissipate the costs of the event can likely withstand the consequences of an extreme weather event. For populations constrained in one of these respects, though, extreme events may entail extreme ecological consequences.

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