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Summary1. Agricultural management of grassland in lowland Britain has changed fundamentally in the last 50 years, resulting in spatial and structural uniformity within the pastoral landscape. The full extent to which these changes may have reduced the suitability of grassland as foraging habitat for birds is unknown. This study investigated the mechanisms by which these changes have impacted on birds and their food supplies. 2. We quantified field use by birds in summer and winter in two grassland areas of lowland England (Devon and Buckinghamshire) over 3 years, relating bird occurrence to the management, sward structure and seed and invertebrate food resources of individual fields. Management intensity was defined in terms of annual nitrogen input. 3. There was no consistent effect of management intensity on total seed head production, although those of grasses generally increased with inputs while forbs were rare throughout. 4. Relationships between management intensity and abundance of soil and epigeal invertebrates were complex. Soil beetle larvae were consistently lower in abundance, and surface-active beetle larvae counts consistently higher, in intensively managed fields. Foliar invertebrates showed more consistent negatively relationships with management intensity. 5. Most bird species occurred at low densities. There were consistent relationships across regions and years between the occurrence of birds and measures of field management. In winter, there was a tendency towards higher occupancy of intensively managed fields by species feeding on soil invertebrates. In summer, there were few such relationships, although many species avoided fields with tall swards. 6. Use of fields by birds was generally not related to measures of seed or invertebrate food abundance. While granivorous species were perhaps too rare to detect a relationship, in insectivores the strong negative relationships (in summer) with sward height suggested that access to food may be the critical factor. 7. While it appears that intensification of grassland management has been deleterious to the summer food resources of insectivorous birds that use insects living within the grass sward, intensification may have been beneficial to several species in winter through the enhancement of soil invertebrates. 8. Synthesis and applications . We suggest that attempts to restore habitat quality for birds in grassland landscapes need to create a range of management intensities and sward structures at the field and farm scales. A greater understanding of methods to enhance prey accessibility, as well as abundance, for insectivorous birds is required.

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a b s t r a c tMonitoring data on hibernating bats were aggregated for the first time across a number of European countries. These supranational trends revealed that nine out of 16 bat species examined increased at their hibernation sites in Europe between 1993 and 2011, while only one is decreasing. This is reflected in the positive trend shown by a prototype multispecies bat indicator which combined the individual species trends. Our findings suggest that after a period of strong decline in the 20th century, populations of most of the investigated bat species are stabilising or recovering, although with profound differences between European bio-geographical regions and countries. Bat populations in the Continental region have a less positive tendency, compared to those in the Atlantic region. More data from more countries may reveal whether these differences are systematical. So far, the prototype indicator covers 9 countries and 16 of the 45 bat species found in Europe. The next steps will be to refine the methodology behind the indicator and to improve the indicator's representation of European bat populations and its capacity to compare trends among biogeographic regions. This should be achieved by participation of more countries and incorporating data from additional bat species, including data collected by other surveillance methods, such as summer roost counts. Robust information on trends in bat populations at a range of geographic scales is essential to the long-term conservation of bats. Further development of this indicator will make an important contribution to conservation of bats because it will stimulate international cooperation and capacity building for monitoring and research, thus exchanging and broadening knowledge of the status of bats and improving the identification of threats.