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Biodiverse areas of traditional low-intensity agriculture in Europe, or ‘High Nature Value’ (HNV) farmland, are supported by European policy and government subsidies. However, HNV areas have declined in extent, contributing to biodiversity decline. If some traditional practices in HNV farmland could be modernised without reducing natural values, this could improve the economic viability of HNV farms, increasing their resilience to economic pressures. Here we compare one traditional and two modernised cereal harvesting methods on machair , an HNV farmed landscape typical of the Scottish islands, focussing on the value of post-harvest stubbles to wintering birds. Following traditional practice, all cereals were mixed species crops comprised of local varieties of small oats, barley and rye. Grain abundance and seed-eating bird use of stubbles was compared across 16 rounds of visits to 15 fields, five under each of three harvest methods: traditional reaper-binder (machinery from 1950–60s), combine-harvesters (1970–80s) and arable silage (1990–2000s). The two forms of harvest modernisation (combine harvester, arable silage) produced stubbles that differed markedly in bird use. Skylark and bunting occurrence, and grain abundance, were 1.7–19 times higher on stubbles following combine harvesting, than on those following arable silage. Unexpectedly, combine-harvester stubbles had similar levels of bird use to those following traditional reaper-binder harvest. Our results suggest that harvesting on machair could be modernised using (older model) combine-harvesters in place of traditional methods, with little impact on stubble value for birds, maintaining this aspect of high nature value. Conversely, modernisation involving more cereals harvested as arable silage, under current practice, is likely to reduce stubble quality for seed-eating birds. Future work could test whether delayed cutting of arable silage might create stubbles of greater value for birds. [ABSTRACT FROM AUTHOR]

Advances in our understanding of recent farmland biodiversity loss have mainly come from studies in Western Europe. The application of such findings to other regions is questionable, however, and limits the outcomes of management actions. To bridge this knowledge gap, we focused on relationships between farmland bird abundance and sward height and crop type, counting breeding birds in three Central European regions with different agricultural histories and practices: the Eastern Czech Republic, Western Germany and Central Poland. We used the skylark ( Alauda arvensis ) as a model species due to its tight association with open habitats year-round and its commonness in European farmland. Skylarks were more abundant in Poland than in Germany and the Czech Republic, probably due to less intensive farmland management. Mean abundance declined with growing sward height from April to June and slightly declined with the number of fields surrounding study sites in all regions. Autumn- and spring-sown cereals hosted the highest abundance of skylarks in May, with lower abundance in maize, oilseed rape and meadows irrespective of region. This variation in skylark numbers suggests a temporal shift in abundance, probably reflecting movement between crops with optimal sward height. Taken together, these results indicate that skylark habitat use is somewhat conserved over regions and this knowledge can be used in management plans throughout Europe. However, the observed differences in skylark abundance between regions suggest that the regional-specific level of agricultural intensity may affect the delivery of conservation benefits from such plans. [ABSTRACT FROM AUTHOR]

Grass fodder crops are attractive nesting habitats for a suite of declining farmland bird species that nest in taller grass swards. Multiple, early silage harvests cause substantial losses of nests and flightless fledglings, making this widespread crop an influential population sink in temperate farmland. We measured the effects of two simple conservation interventions (raised cutting heights and delayed mowing) designed to increase the reproductive output of a multi-brooded passerine (skylark Alauda arvensis ). Annual reproductive output of independent juveniles (fecundity) was quantified using a stochastic re-nesting model that allowed us to investigate the impacts of a wide range of potential management interventions (varying cutting heights, dates and machinery) at minimal cost. Under typical silage management mean skylark fecundity was only 13–17% of the level required for metapopulation stability (the replacement rate). 12–54% of nests and 28–44% of fledglings survived a typical silage harvest with most losses caused by abandonment of nests covered by cut grass, crushing by wheels or predation soon after mowing. Delaying mowing increased fecundity, but only up to a maximum of 44% of the replacement rate. Raising cutting heights had a negligible impact on fecundity. Asynchrony between nesting attempts (due to predation, starvation and protracted delays between nesting attempts) resulted in few attempts taking place when they could benefit from the interventions. In the absence of mowing, fecundity was only 47% of the replacement rate, due to low reproductive output per nesting attempt, while simulations showed that increasing output per nest would have the largest impact on fecundity. Conservation effort should focus on providing alternative high fecundity breeding and foraging habitats at the landscape scale, to counteract silage fields’ action as a sink for skylark populations in livestock-farming areas. These conclusions are likely to apply to other multi-brooded ground-nesting species. [ABSTRACT FROM AUTHOR]

Highlights: [•] We estimate effects of grass buffer strips on in-field biodiversity. [•] Buffer strip fields support more beetles and spiders compared to control fields. [•] Buffer strip fields also support more skylarks irrespective of sowing regime. [•] Buffer strip effects are expected to depend on landscape scale implementation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Skylarks favour field margins for foraging over all other habitat types. [•] Field margin visiting rates are low when the distance from the nest exceeds 100m. [•] The efficiency of field margins is hampered by suboptimal spatial arrangement. [Copyright &y& Elsevier]

Abstract: The study compares populations of two typical open farmland bird species, the skylark and the meadow pipit, on fields with open in-field and subsurface drainage systems in Finland. Data are derived from the national monitoring of farmland birds for 2002–2009 and are based on territory mapping. Generalised additive mixed models with repeated measures were used to investigate territory density and temporal population trends of the species on crop and grassland fields with two types of drainage. The results provided evidence for a higher habitat value of fields under open drainage (ODF) than fields with subsurface drainage (SDF) for the meadow pipit at any given year. Both species’ trends were significantly positive on ODF while trends on SDF were not significantly directional. This strongly suggests that foraging resources and nest survival of individuals breeding in ODF habitats rise above those of SDF habitats. The retention of the remaining ODF as part of the agri-environmental and relevant land-use policies could contribute to stabilisation and enhancement of populations of farmland birds for regions in Europe and elsewhere with the need for drainage. [Copyright &y& Elsevier]

Abstract: Among 66 Estonian farms, representing three subsidy types, birds (especially Sylvia communis and Saxicola rubetra) were more abundant in organic farms that received the largest subsidies and were typically situated in structurally diverse landscapes with a high share of grasslands. Vertical landscape elements most clearly promoted species richness of breeding birds and S. communis. However, among management-related environmental factors considered, only fertilizer input was consistently subsidy-type dependent (highest inputs at medium subsidy levels). High inputs reduced species richness of breeding birds and the density of Alauda arvensis. When environmental factors were accounted for, no significant influences of the subsidy type on birds were observed, but region-specificity remained significant. Our results indicate that differentiation of national subsidies in the AES framework does not necessarily lead to distinct environmental effects, and that targeting of the subsidies on particular species is necessary to effectively improve current environmental conditions. [Copyright &y& Elsevier]

Abstract: Variation in the distributions of different species of lark was assessed along the two main agricultural gradients in the steppe and semi-desert zones of Kazakhstan: the intensity of grazing and the time since abandonment of cereal fields. Vegetation structure and composition varied significantly with time since abandonment, and with changing grazing pressure. The studied lark species responded in non-linear ways to both these gradients and showed a high degree of niche separation, with black lark, calandra lark and skylark preferring denser and taller vegetation compared to white-winged lark and short-toed lark. Lark populations generally are likely to have benefited from agricultural abandonment and a decline in livestock numbers over large parts of the steppes and semi-deserts of the former Soviet Union. The results suggest that an assessment of future changes in steppe bird communities based upon projections of changes in the area of gross habitat types can be improved by a better understanding of the responses of different species to more subtle environmental gradients. [Copyright &y& Elsevier]

Abstract: Explanations for causes of farmland biodiversity declines often assume no spatial or temporal variation in the effects of land use on species abundance and performance. For example, European populations of skylark are assumed to have declined partly due to the switch from spring sown to autumn sown crops. Still, land use preferences of farmland birds may vary with region, landscape structure and time in the breeding season. We inventoried 430 transects in 36 landscape plots (each 25km2) in three major agricultural regions of southern Sweden and show that land use-specific densities of skylarks display strong temporal and regional differences. Pre-nesting densities in late April–early May were highest in autumn sown cereals and other arable land use with vegetation, but decreased during the course of the breeding season such that densities in spring sown cereals were slightly higher than those in autumn sown cereals late in the season. This temporal shift in crop-specific densities of skylarks differed between regions. Temporal patterns of crop-specific densities of skylarks could be explained in terms of vegetation-dependent nest predation risk and foraging conditions. We suggest that land use preferences of farmland birds often could be expected to display a temporal and spatial variation and this should be reflected in a more flexible, context-dependent approach for the conservation of farmland biodiversity. [Copyright &y& Elsevier]

This 6-year experimental study measured the response of bird populations and abundance to combinations of mixed cropping and low pesticide regimes associated with a commercial crop rotation. The results show a rapid and sustained population increase among a wide range of bird species, in contrast to local regional trends for the same species. Seventy percent of the increase occurred within the first 3 years of the experiment, with species of high conservation concern, and those monitored as environmental indicators on lowland farmland in the UK, increasing on average, by 30% and 20% respectively (reaching respective peaks of 44% and 33% after 4 years). For some individual species, the increase was higher still, i.e., 300% (1–4 pairs) for grey partridge (Perdix perdix) and 46% (13–19 pairs) for skylarks (Alauda arvensis) in peak years. The results demonstrate that bird species typical of lowland arable farmland in the UK are responsive to suitable farm-scale changes in habitat and food provision (roughly, manipulation within less than 1-km2). They show that the carrying capacity of modern, commercially viable, arable farmland can be increased significantly for birds, in this case, mainly by using crops mosaics to create habitats alongside the appropriate use of herbicides on non-cropped habitats. [Copyright &y& Elsevier]

Abstract: Agricultural intensification is responsible for the dramatic decline of farmland bird populations in the European Union (EU). The joining of eight Central and Eastern European (CEE) countries to the EU will re-structure agriculture there. One of the main threats is the intensification of farmland management. Can agri-environmental programs balance the expected decline in bird assemblages of the CEE countries if farming will be intensified? We studied this question by comparing bird assemblages of 42 extensively and intensively grazed paired fields in three regions of Hungary (alkali steppes and meadows in Central Hungary and alkali steppes in Eastern Hungary). Bird assemblages varied significantly across regions and grazing intensity. Intensively grazed sites showed a higher species number and diversity, but lower densities than the extensive sites. This is probably the consequence of higher landscape diversity of intensive sites, which included farm buildings, shelters, wells and other structures. Several bird species, mainly with European conservation concern, showed contrasting responses to grazing intensity in the three regions, including key grassland species (black-tailed godwit Limosa limosa, redshank Tringa totanus, skylark Alauda arvensis and corn bunting Emberiza calandra). Therefore, threat and sensitivity to grassland characteristics are correlating. Although many of the declining species of Western Europe are still abundant in Hungarian grasslands, our results project the threat of the expected intensification. This study showed that it is not possible to provide a general grassland management scheme that will favour all bird species in all regions of Hungary. In the process of integrating to the EU and re-structuring agriculture, the establishment of scientifically sound schemes is urgent. [Copyright &y& Elsevier]

Monitoring bird populations is labour-intensive and requires expert knowledge. Development of more cost-effective methods of bird species monitoring is therefore desirable. Simple rule-based (RB) models were developed that predicted the presence of birds in lowland arable farmland in the breeding season. These were based on the presence of key habitat elements required by the birds identified from the literature. Habitat data and bird data were collected independently from 525 transects each of which ran along a field margin. Model performance was tested in five species: grey partridge Perdix perdix, skylark Alauda arvensis, linnet Carduelis cannabina, corn bunting Miliaria calandra and yellowhammer Emberiza citrinella. RB models were not good predictors of species presence. Model performance did not vary appreciably between early or late breeding season or according to geographic region. Skylark had the best performing model, but even in this case the predictive power was low. Prediction of species presence from habitat survey data is therefore unlikely to be a cost-effective method of monitoring birds on British farmland. [Copyright &y& Elsevier]

Density and habitat selection of skylarks Alauda arvensis L. were studied in 65 localities of central and southern Iberia. Density was analysed in relation to climatic and geographic variables, as well as to habitat type, by means of linear regression models. Habitat selection was assessed by analysing the relationship of the species’ presence with vegetation structure using logistic regression. When all localities were considered, density of breeding skylarks was associated to altitude. During winter, skylark range increased and abundance was related to habitat type. Skylark winter density in dry pasture was 10–20 times higher than in any other habitats. Differences between winter and spring density presented a pattern similar to that found in winter and maximum values were reached in dry pasture. Summer and winter skylark presence showed an association to pasture and shrub <40 cm cover. These results demonstrate the importance of Iberian dry pastures as a wintering habitat for a considerable proportion of skylark European populations. The marked reduction of these habitats in Iberia over the last decades, associated to changes in agricultural practices, might contribute to the overall decline of the species. [Copyright &y& Elsevier]