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Farmland abandonment and the accompanying natural succession are largely perceived as unwanted amongst many European conservationists due to alleged negative effects on biodiversity levels. Here, we test this assumption by analysing alpha, beta and gamma diversity patterns of macro-moth communities in habitats on an ecological succession gradient, from extensively managed meadows to scrub-encroached and wooded sites. Macro-moths were light-trapped at 84 fixed circular sampling sites arranged in a semi-nested design within the National Park of Peneda-Gerês, NW-Portugal. In total, we sampled 22825 individuals belonging to 378 species. Alpha, beta and gamma diversity patterns suggest that farmland abandonment is likely to positively affect both overall macro-moth diversity and forest macro-moth diversity, and to negatively affect species diversity of non-forest macro-moth species. Our results also show that spatial habitat heterogeneity is important to maintain gamma diversity of macro-moths, especially for rare non-forest species and habitat specialists.

The increasing conversion of agricultural and natural areas to human-dominated urban landscapes is predicted to lead to a major decline in biodiversity worldwide. Two conditions that typically differ between urban environments and the surrounding landscape are increased temperature, and high patch isolation and habitat turnover rates. However, the extent and spatial scale at which these altered conditions shape biotic communities through selection and/or filtering on species traits are currently poorly understood. We sampled carabid beetles at 81 sites in Belgium using a hierarchically nested sampling design wherein three local-scale (200 × 200 m) urbanization levels were repeatedly sampled across three landscape-scale (3 × 3 km) urbanization levels. First, we showed that communities sampled in the most urbanized locations and landscapes displayed a distinct species composition at both local and landscape scale. Second, we related community means of species-specific thermal preferences and dispersal capacity (based on European distribution and wing morphology, respectively) to the urbanization gradients. We showed that urban communities consisted on average of species with a preference for higher temperatures and with better dispersal capacities compared to rural communities. These shifts were caused by an increased number of species tolerating higher temperatures, a decreased richness of species with low thermal preference, and an almost complete depletion of species with very low-dispersal capacity in the most urbanized localities. Effects of urbanization were most clearly detected at the local scale, although more subtle effects could also be found at the scale of entire landscapes. Our results demonstrate that urbanization may fundamentally and consistently alter species composition by exerting a strong filtering effect on species dispersal characteristics and favouring replacement by warm-dwelling species., (© 2017 John Wiley & Sons Ltd.)

The increasing urbanization process is hypothesized to drastically alter (semi‐)natural environments with a concomitant major decline in species abundance and diversity. Yet, studies on this effect of urbanization, and the spatial scale at which it acts, are at present inconclusive due to the large heterogeneity in taxonomic groups and spatial scales at which this relationship has been investigated among studies. Comprehensive studies analysing this relationship across multiple animal groups and at multiple spatial scales are rare, hampering the assessment of how biodiversity generally responds to urbanization. We studied aquatic (cladocerans), limno‐terrestrial (bdelloid rotifers) and terrestrial (butterflies, ground beetles, ground‐ and web spiders, macro‐moths, orthopterans and snails) invertebrate groups using a hierarchical spatial design, wherein three local‐scale (200 m × 200 m) urbanization levels were repeatedly sampled across three landscape‐scale (3 km × 3 km) urbanization levels. We tested for local and landscape urbanization effects on abundance and species richness of each group, whereby total richness was partitioned into the average richness of local communities and the richness due to variation among local communities. Abundances of the terrestrial active dispersers declined in response to local urbanization, with reductions up to 85% for butterflies, while passive dispersers did not show any clear trend. Species richness also declined with increasing levels of urbanization, but responses were highly heterogeneous among the different groups with respect to the richness component and the spatial scale at which urbanization impacts richness. Depending on the group, species richness declined due to biotic homogenization and/or local species loss. This resulted in an overall decrease in total richness across groups in urban areas. These results provide strong support to the general negative impact of urbanization on abundance and species richness within habitat patches and highlight the importance of considering multiple spatial scales and taxa to assess the impacts of urbanization on biodiversity. [ABSTRACT FROM AUTHOR]

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Abstract: Although intensive forestry practices have greatly reduced the biodiversity of native woodland, sympathetic management offers much potential to reverse these negative trends. We tested, using a species-rich group, whether woodland conservation management practices could be of overall benefit, for threatened generalists and specialists alike. Our landscape-scale light-trap experiment compared presence/absence, abundance and species richness of macro-moths at 36 repeatedly sampled sites from six experimental ‘woodland management’ treatments. We recorded 11,670 individuals from 265 species. Our results show that the sheltered, dark, humid, late-successional, high deciduous forest biotope is characterised by high numbers of both individuals and species of moth, and is especially important for some scarce and specialist species of conservation concern. Coppicing and ride widening, which open up dense forest structures, are also valuable woodland conservation tools for macro-moths. Specifically, we show that the mechanism behind the pattern of increased species richness at the woodland-scale involved an increased structural and hence increased micro-climatic and resource diversity for species with an affinity for more open biotopes. This benefits generalist species of conservation concern. Additionally, we show that woodland area is an important factor affecting both moth abundance and species richness in coppiced plots, especially so for nationally declining and severely declining species, suggesting that larger woodlands offer the best opportunities to increase biodiversity through active coppice management. Based on these complementary findings we recommend zoning woodland conservation management practices to take into account the differential value of successional stages for different ecological groups of Lepidoptera. [Copyright &y& Elsevier]

Abstract: Agri-environment schemes are the main policy instruments for reversing declines in farmland biodiversity, but there is scope for improvement. Within an intensive agricultural landscape, a mark-release-recapture experiment was used to investigate the relative effects on the number of adults of 23 moth species of two landscape features (wide field margins and hedgerow trees) that may feature within agri-environment schemes. Species belonged to either the grass/herb- or shrub/tree-feeders’ guild. Margin width did not affect the number of individuals, in either guild. Numbers of shrub/tree-feeding individuals were higher at sites with hedgerow trees, but not so for this guild''s two most mobile species, nor for the grass/herb-feeders, which were 30% more mobile. The results show that hedgerow trees increase adult moth numbers because they are shelter-providing resources in typically exposed agricultural landscapes, rather than due to being larval food resources. Hedgerow tree retention and establishment options should be part of efficient general agri-environment schemes, while grassy wide field margins may not always deliver gains, at least not when implemented at the field-scale. [Copyright &y& Elsevier]

1. Agricultural intensification is the main driver of global biodiversity loss. Agri-environment schemes (AES) are policy tools to counter this, but they need to be made more effective. 2. Here, we focus on the resource quality of hedgerows and woodland edges, which are widespread elements of most agricultural landscapes in Europe. We analyse a set of structural factors and assess their relative importance for the Brown hairstreak butterfly. This species suffered severe declines because of agricultural intensification that may be indicative of changes for other widespread insect species that use hedgerows as resources. 3. Egg-deposition preferences were assessed by comparing egg densities among hostplant sections in two study landscapes. All sections were systematically searched during four consecutive years, resulting in 745 observed eggs. 4. We demonstrate that the ground plan outline and aspect of landscape elements, the relative position within landscape elements, and the amount of young hostplant growth are particularly relevant in explaining observed egg densities, and we link their importance with the butterfly’s behavioural biology. 5. Our study provides evidence that management focused on providing ample young growth, and transforming the landscape element ground plan outline from linear to a scalloped pattern, would benefit ectothermic species by providing more sheltered micro-climates when they use these structural resources for breeding, feeding and moving through typically exposed agricultural landscapes. We believe that integrating such management options within general AES would translate into effective, large-scale conservation measures for Brown hairstreaks and other species alike. [ABSTRACT FROM AUTHOR]

How best to optimize the biodiversity gain from agri-environment schemes (AES) has recently been identified as a key policy-relevant question. Here, the effects of two features of lowland agricultural landscapes on the abundance and diversity of larger moths are contrasted. Although both features bring about positive effects, hedgerow trees have a larger impact than 6m wide grassy field margins. Whilst AES payments are given to create and maintain grass margins, no financial reward is currently offered for the retention of hedgerow trees. Furthermore, it was only in areas where the amount of land under AES was experimentally increased, by targeting farmers, that the presence of hedgerow trees resulted in a substantially higher abundance (+60%) and diversity (+38%) of moths. Thus, by using larger moths as bio-indicators of landscape-scale quality, it is demonstrated that improvements to the cost-effectiveness of AES could be achieved, firstly, by providing more appropriate financial rewards to farmers for different landscape features, and secondly, through landscape-scale targeting of farmers to encourage participation in AES. [Copyright &y& Elsevier]

Agri-environment schemes (AES) are widely used policy instruments intended to combat widespread biodiversity declines across agricultural landscapes. Here, using a light trapping and mark-release-recapture study at a field-scale on nine common and widespread larger moth species, we investigate the effect of wide field margins (a popular current scheme option) and the presence of hedgerow trees (a potential scheme option in England) on moth abundance. Of these, we show that wide field margins positively affected abundances, although species did not all respond in the same way. We demonstrate that this variation can be attributed to species-specific mobility characteristics. Those species for which the effect of wide margins was strongest covered shorter distances, and were more frequently recaptured at their site of first capture. This demonstrates that the standard, field-scale uptake of AES may be effective only for less mobile species. We discuss that a landscape-scale approach, in contrast, could deliver significant biodiversity gains, as our results indicate that such an approach (perhaps delivered through targeting farmers to join AES) would be effective for the majority of wider countryside species, irrespective of their mobility level. [Copyright &y& Elsevier]

Visually cued mate location behaviour in insects such as butterflies is typically classified by ‘wait or seek’ dichotomies. Perching males adopt a sit-and-wait strategy at a particular spot rising to intercept passing females (which is often done in an aggressive territorial way), whereas patrolling males are permanently on the wing searching for females. The potential influence of changes in landscape caused by habitat fragmentation on mate location behaviour has only rarely been addressed. We investigated this behaviour among populations of the speckled wood butterfly, Pararge aegeria, living in continuous woodland versus highly fragmented agricultural landscape with hedgerows and small patches of woodland. In the latter landscape males showed higher levels of aggressive fast take-offs (an indicator of territorial perching), but also higher levels of displacement (an indicator of patrolling). In an independent census, behaviour intermediate between perching and patrolling was much more frequent in the agricultural landscape than in the woodland landscape. Our results suggest that the dichotomy of perching versus patrolling as typically observed in woodland fades away in highly fragmented agricultural landscape. We discuss our results in relation to differences in densities and thermal properties of both types of landscape. [Copyright &y& Elsevier]