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Declines in farmland biodiversity remain evident despite over three decades of research and implementation of agri‐environment schemes (AES). Although positive effects of AES are often demonstrated locally or in the short term, studies exploring longer term trends in biodiversity often show contradictory results. Evidence for the potential of AES to drive beneficial changes in populations remains sparse, especially for mobile taxa such as birds and butterflies.We analysed the abundance of 12 widespread bird and 9 butterfly species from a 10‐year study of AES intervention in a farmland landscape in southern England. We compared estimates of annual population growth rates from our study landscape with rates derived from large‐scale national monitoring schemes in equivalent landscapes without substantial AES.Species trends in our study landscape were frequently stable or increasing, in contrast to concurrent declining trends in equivalent landscapes without AES. These differences were significant for total abundance of granivorous species and for chaffinch Fringilla coelebs, blue tit Cyanistes caeruleus and great tit Parus major individually. For butterflies, differences in trends were significantly more positive for gatekeeper Pyronia tithonus and green‐veined white Pieris napi, while small white P. rapae showed a trend that was significantly more negative in our study landscape.Synthesis and applications. Our results demonstrate that, for some bird and butterfly species, the higher abundances associated with areas of AES uptake within a typical commercial farmland landscape can co‐occur with positive or stable population trends over long time scales and that these trends can show significant differences from those in equivalent landscapes without substantial AES interventions. Our results suggest that previously observed inconsistencies in AES benefits may in part reflect a lack of long‐term studies with accurate data on AES uptake and quality (i.e. successful implementation and management). Our results, thus, affirm the importance of delivering and monitoring high‐quality AES options if the design and implementation of the next generation of AES is to achieve significant benefits for biodiversity. [ABSTRACT FROM AUTHOR]

The influence of large‐scale variables such as climate change on phenology has received a great deal of research attention. However, local environmental factors also play a key role in determining the timing of species life cycles. Using the meadow brown butterfly Maniola jurtina as an example, we investigate how a specific habitat type, lowland calcareous grassland, can affect the timing of flight dates. Although protracted flight periods have previously been reported in populations on chalk grassland sites in the south of England, no attempt has yet been made to quantify this at a national level, or to assess links with population genetics and drought tolerance. Using data from 539 sites across the UK, these differences in phenology are quantified, and M. jurtina phenology is found to be strongly associated with both site geology and topography, independent of levels of abundance. Further investigation into aspects of M. jurtina ecology at a subset of sites finds no genetic structuring or drought tolerance associated with these same site conditions. [ABSTRACT FROM AUTHOR]

Aim: Climate change has been predicted to facilitate poleward expansion of many early‐successional specialist invertebrates. The Grizzled Skipper, Pyrgus malvae, is a threatened butterfly in long‐term decline that has not met expectations of northern expansion in Britain, possibly indicating that climate change has not improved northern habitat suitability or that another driver (e.g. land use change) is masking its effects. Here, we explore the effect of climate on population size trends over four decades, and whether any regions show an improving population trend that may be a precursor to northern expansion. Examining detailed spatio‐temporal abundance data can reveal unexpected limitations to population growth that would not be detectable in widely used climate envelope models. Location: Central and southern England. Methods: Mixed models were used to investigate P. malvae population size in relation to time and monthly climate measures across its UK range since 1976, based on repeated transect walks. Results: We found that P. malvae population size declined more over time in the north and west of its UK range than in the south and east, and was negatively related to high December temperature and summer rainfall. However, the effect sizes of temperature and rainfall were minimal. Main Conclusions: The last 40 years of climate change have not ameliorated climate suitability for P. malvae at its range edge, contrary to expectations from spatial‐only climate envelope models. The clear long‐term downward trends in population size are independent of climate change and we propose probably due to habitat deterioration. Our findings highlight potential hazards in predicting species range expansions from spatial models alone. Although some climate variables may be associated with a species' distribution, other factors may be more dominant drivers of trends and therefore more useful predictors of range changes. [ABSTRACT FROM AUTHOR]