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Hedgerows can provide key semi-natural habitat within intensively farmed landscapes, and can deliver habitat and resources for a range of important wildlife, in addition to supporting ecosystem services. The value of hedgerows in supporting wildlife varies, depending on the management applied. Hedgerow management options have high uptake within agri-environment schemes (AES), both historically in Environmental Stewardship (ES) and in the current Countryside Stewardship (CS) scheme, including the Hedgerow and Boundaries grant. Previous studies on hedgerow management have shown substantial potential effects of hedgerow management regimes on the provision of resources for overwintering wildlife (Sparks and Croxton, 2007), and some indication of benefits for wildlife (Maudsley et al. 2000), but have not been quantified or rigorously tested. Here, results from three large-scale manipulative field experiments are presented, to assess different hedgerow management and rejuvenation methods in relation to the provision of resources for wildlife, and the response of invertebrates. The aims of this study were: 1) To examine the effects of simple hedgerow cutting regimes promoted by CS and ES, and the potential for cutting to allow incremental growth, on the quality and quantity of wildlife habitat, and food resources in hedgerows. 2) To identify, develop and test low-cost, practical options for hedgerow restoration and rejuvenation applicable at the large-scale under both CS and ES. Methods Two experiments were conducted to assess hedgerow cutting treatments. Experiment 1 consisted of replicated cutting frequency (every year vs. every two years vs. every three years) and timing (autumn vs. late winter) treatments, applied to replicate sections of hawthorn-dominated hedgerow at a single site in Cambridgeshire. Experiment 1 pre-dated this research project, and so it provided initial findings on these cutting regimes early in the project, which informed the revision of ES hedgero

Neonicotinoid seed dressings have caused concern world-wide. We use large field experiments to assess the effects of neonicotinoid-treated crops on three bee species across three countries (Hungary, Germany, and the United Kingdom). Winter-sown oilseed rape was grown commercially with either seed coatings containing neonicotinoids (clothianidin or thiamethoxam) or no seed treatment (control). For honey bees, we found both negative (Hungary and United Kingdom) and positive (Germany) effects during crop flowering. In Hungary, negative effects on honey bees (associated with clothianidin) persisted over winter and resulted in smaller colonies in the following spring (24% declines). In wild bees (Bombus terrestris and Osmia bicornis), reproduction was negatively correlated with neonicotinoid residues. These findings point to neonicotinoids causing a reduced capacity of bee species to establish new populations in the year following exposure.

This report details work conducted under a Memorandum of Agreement (MoA) between Natural England and the Centre for Ecology and Hydrology and British Geological Survey, initiating a programme of linked vegetation and hydrological studies. As stated in the MoA, the overall aim of this collaboration is ‘To improve the conservation status of dune wetlands of European importance and the condition of the dune wetland features of sand dune SSSIs identified in Appendix 1, through a major improvement in understanding of dune ecohydrological functioning.’ In consultation with Natural England, nine sites were selected for survey of the dune wetland component in the summer of 2012, aiming to partially repeat the Sand Dune Survey of Great Britain (SDGB) in the late 1980s. The selected sites hold 77% of the English dune wetland resource. At each site, all dune wetlands were mapped, with the exception of the three sites on the Sefton Coast, where the majority of the core area was mapped but not satellite areas. For each site the geological setting, surface topography, surface water features, climatic setting and land cover were assessed and the most important hydrological processes identified.

In a four-year experimental study, the effects of various pre-sowing disturbance treatments (band-spraying with herbicide; soil harrowing; creation of ridge and furrow structures) and of post-establishment sward management regimes on the performance of habitat specialist plant species known to perform poorly in the restoration of lowland calcareous grassland was tested. It was found that as with generalist species, pre-sowing disturbance is key to successful establishment. Ridge and furrow appeared to be a good alternative to more traditional means of pre-sowing disturbance such as soil harrowing in particular for low-statured species of low competitive ability with a known preference in ancient grassland for south-sloping sites and ant hills. It appears that three years of experimental sward management may have been too short a period to allow solid conclusions on the effects of various alternative options.

Intensive agriculture has contributed to serious declines in abundance and diversity of pollinating insects. The agri-environment schemes (AES) aim to conserve and enhance the pollination service to crops and wildflowers by providing habitats rich in pollen and nectar. Research suggests that current management prescriptions are failing to provide habitats of sufficient quality and longevity. We investigated the performance of 10 low cost seed mixtures over 3 years. The seed mixtures comprised legume species sown with grasses of differing competitive ability. The typical practice of sowing tall and competitive grass species significantly reduced cover of legume species over time. Persistence of legumes was significantly better in mixtures sown either without grasses, or with fine-leaved grasses. Winter application of graminicide in year 3 resulted in reduced competition from grasses, and an increased cover of sown forbs and undesirable weed species. This resulted in significantly a higher abundance and diversity of bumblebee species.

Intensive agriculture has contributed to serious declines in the diversity and geographic range of the UK arable flora. The agri-environment schemes have a number of management options which aim to conserve and enhance populations of scarce arable plants. Research suggests that competition from perennial and grass species is a serious constraint on the long term success of these management prescriptions. We present the results of a 2 year split-plot randomised block experiment to examine the effects of 1) herbicide weed control measures and 2) time of cultivation on the survival and spread of a sown scarce arable plant community. Autumn and spring graminicide application significantly reduced the cover of competitive grasses and increased the species richness of scarce arable plants. Autumn cultivation significantly increased the cover and species richness of scarce arable plants, and reduced the cover of grasses. The results are discussed in the context of future agri-environment scheme prescriptions for the practical, in situ and rotational management of arable plant communities.

There are now many competing pressures on farmland to provide space for urban development, transport, wildlife habitat, and a wide range of essential ecosystem goods and services. Future agri-environment schemes will need to be multi-functional and more efficient in their use of the land resource. We present the results of an experiment to examine the feasibility of developing high quality, multi-purpose habitats for both birds and pollinating insects on field margins. Foraging activity of bumblebees and butterflies was recorded in stands of nine seed crops species and four pollen- and nectar-rich species between May and September. Most perennial species did not flower until year 2 when they provided a similar flower resource to that of the annual species. Short-tongued bees showed a marked preference for annual seed crop species. Long-tongued bees showed a significant preference for perennial legumes. Butterfly abundance was also highest on the perennial legumes.

The Hillesden experiment is a farm-scale study evaluating the performance of options under Environmental Stewardship. We describe bird usage of winter seed patches (20 patches; three seed mixes) in relation to seed depletion and variation between individual patches. Seed retention declined exponentially in all three mixes; 50% depletion occurred by late November, reaching 80-90% before mid January. In mid winter, Fodder Beet retained more seed (c. 80%) than Millet, Kale, Fodder Radish and Triticale (20-40%). Bird numbers peaked in December/early January (seed depletion 70-90%), but declined rapidly in late January coinciding with seed exhaustion. Seed yields varied between patches (minimum < 1% of maximum). If all patches had performed at the maximum, yield would have increased by about 64%. Bird counts also varied greatly between patches, but trends with seed yield were positive. At a farm-scale, winter bird abundance was significantly greater (granivorous species + 415%) when patches were available.

Miscanthus is a newly introduced crop grown primarily to produce biomass for energy production and the area grown in the UK is anticipated to increase. Major differences in crop management from conventional arable crops have led to speculation that miscanthus may also have effects on farmland biodiversity. Six miscanthus fields were paired with six of a conventional crop, winter wheat, and bird diversity and abundance were compared in winter and during the breeding season along with potential food sources. Miscanthus fields had a greater abundance and diversity of birds than did wheat in winter and summer. In winter, the greater numbers of birds in miscanthus fields were probably attracted by the shelter provided by the crop and by the abundance of non-crop plants. During the breeding season, the abundance of non-crop plants in miscanthus fields, and greater numbers of insects associated with these plants, provided food resources. However, the miscanthus crop plants provided less insect food than wheat crop plants. Changes in crop structure during the breeding season influenced the breeding birds. The results from this study suggested that an increase in the area of miscanthus grown in the UK may have temporary benefits for farmland bird populations during establishment. These benefits are likely to diminish with age of crop and as crop management improves with experience. Management for wildlife will be required to maintain the diversity of features attractive to birds because many of these will be lost if miscanthus is managed solely to maximise crop yields.

Intensive farming has contributed to the serious declines in abundance and geographic range suffered by several bumblebee species in Europe and North America. Recent UK agri-environmental policy aims to conserve and restore bumblebee populations by providing foraging habitats on arable field margins. We examined the effectiveness of strategies to achieve this, including sowing seed mixtures of (1) tussocky grass species, (2) wildflowers and (3) pollen- and nectar-rich plants. These were compared to conventionally managed cereal crops. Sampling was undertaken in 32 10 × 10 km squares throughout England, each containing a sample of the different field margin types. Bumblebee abundance in July and August was significantly higher on pollen and nectar margins (86 ± 14 bees per 100 m) compared with wildflower margins (43 ± 14), mature grass margins (6 ± 14) and recently sown grass margins (8 ± 4). Bees were virtually absent from the cereal crop (0.2 ± 0.1). Bumblebee species richness was significantly higher on margins sown with either wildflowers or the pollen and nectar mix. There was evidence that richness of the bumblebee assemblage at the 10 × 10 km square scale was positively correlated with land use heterogeneity, the proportion of grassland, and the abundance and richness of dicotyledon flowers. The abundance of long-tongued bees per margin was explained by the number of pollen and nectar agreements per 10 × 10 km square, together with flower abundance. Future research is required to determine the quantity and location of foraging habitat required to sustain bumblebee populations at the landscape scale.