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European farmland hosts a species assemblage of animals and plants which have undergone declines through the late twentieth and early twenty-first centuries, at least partly as a result of increased productivity. Further increases in human populations, changes in availability and cost of raw materials, policy constraints, price volatility and climatic changes will further drive greater efficiency and high yields in agriculture, with the risk of further adverse environmental impacts. We assess the effects of different management priorities (production-driven cropping vs. wildlife-friendly farming) at an arable farm in eastern England on food production, greenhouse gas (GHG) emissions and biodiversity. We modelled one actual and three alternative cropping scenarios using actual yields from the farm over 13 years, to calculate total yields and those foregone for agri-environmental measures. We measured crop yields, relative abundance of 19 farmland bird species, and CO2and N2O emissions related to crop production. Removing up to 10.5% of land from production coupled with a more diverse rotation (including legumes) resulted in a large increase in breeding birds (177%) and reduction of 9.4% in GHG emissions at the cost of 9.6% of food energy. Food protein lost was only 2.9%. A smaller increase in bird numbers of 50% could be achieved at a much smaller cost to yield (∼1.7% energy or protein) but with correspondingly smaller emissions reductions (1.2%). Results are discussed within the context of continued biodiversity loss to agriculture, increasing food demand and changing diets. [ABSTRACT FROM AUTHOR]

Agri-environment schemes (AES) are the main policy mechanism available to reverse the widespread losses of farmland biodiversity across Europe. Previous examples of AES enhancing the abundance of farmland birds have been restricted to targeted species recovery programmes, often with bespoke habitat management and high levels of advisory support for landowners. Here, we tested whether standard higher-tier AES agreements targeted at multiple species and with lower levels of advisory support than targeted species recovery programmes can enhance the breeding densities of farmland birds. Surveys of breeding birds were undertaken during 2008 and 2011 on 65 farms under higher level stewardship (HLS) and 21 farms lacking AES interventions, in three regions of England. After allowing for any impacts of predator control, changes in density were more positive on HLS farms in at least one region for six priority species. Five of the six species had mixed diets and were predominantly associated with field edges; the other (lapwing) probably responded to the provision of field-centre fallow plots. Changes in bird numbers were not consistently related to the extent of AES habitat provision. This is the first study to demonstrate that standard AES management without substantial ongoing advisory support can increase or maintain the densities of widespread declining species. [ABSTRACT FROM AUTHOR]

Between 1988 and 2007, set-aside, a European Commission production control measure, took an average of 10% of arable farmland in the EU out of production each year. In 2007, the set-aside rate was set to 0% and the scheme was later abandoned altogether. By assessing associations of farmland birds with set-aside and quantifying the extent of set-aside loss, this study aims to assess the implications of set-aside loss for farmland bird conservation. During the lifespan of set-aside, a large number of studies assessed the biodiversity value of set-aside and other agricultural crops and habitats. Where possible we considered measurable benefits of set-aside. However, some studies did not specify the type of set-aside and in some cases set-aside fields were grouped with cereal stubble fields. In these cases, we took the pragmatic approach of assessing the value of generic stubble fields as a conservative minimum estimate of the value of set-aside fields. A re-analysis of data from 30 intensive studies demonstrates that farmland bird densities tended to be higher on set-aside than on either cereal or oilseed rape crops. Without mitigation, these are the two crops likely to replace most set-aside fields. We estimate that 26-52% of the farmland populations of key granivorous passerines were present on stubble fields, giving an indication of the proportion of birds likely to be present on set-aside fields within this broader category. An extensive survey of lowland farmland during winters 1999/2000, 2000/2001 and 2002/2003, repeated in February 2008, showed a doubling of the number of 1-km squares with no stubble and a halving of the number of squares with more than 10 ha of stubble. After set-aside abandonment, 72% of squares had no stubble in the important late winter period, confirming that many of the former stubble fields were retained as set-aside. A simple correlative model suggests that this could cause a small increase in the rate of decline of Skylark Alauda arvensis and Yellowhammer Emberiza citrinella populations, assuming causal links between stubble area and demography. However, even if this assumption cannot be supported, these results clearly indicate that a significant proportion of some farmland bird populations will need to find alternative breeding and foraging habitats. [ABSTRACT FROM AUTHOR]

Some agri-environment schemes promote the creation and management of a variety of non-crop habitats on farmland in the UK, yet there has been relatively little monitoring to assess how species, particularly birds, use these habitats. The present study deals with a declining UK farmland bird species, yellowhammer Emberiza citrinella, and considers to what extent grass margins of arable fields are used as a foraging habitat when feeding nestlings. Studies were carried out in lowland mixed farmland in southern England.Grass margins and other non-crop field boundary habitats, such as hedgerows and ditches, were selected relative to cropped areas by yellowhammers. No significant difference was found between use of cut and uncut grass margins. Studies have shown that grass margins support high densities of invertebrates and their provision at the edge of arable fields would benefit yellowhammers during the breeding season both as habitat for prey and as nesting habitat. During the breeding season from May to August, management should create cut and uncut grass margins in close proximity to each other. This could be achieved by cutting only the outer edge of the grass margin, maintaining cover next to the hedgerow. Cut areas would provide easier access to food resources for birds and prevent weed encroachment to the crop, whilst adjacent uncut areas would maintain invertebrate sources and provide nesting cover for yellowhammers. [Copyright &y& Elsevier]