Forest cover enhances pest control by birds and bats independently of vineyard management intensity

Agricultural intensification substantially threatens farmland communities and associated ecosystem services. More specifically, landscape simplification and agrochemical use can significantly alter the activity of natural enemies, contributing to hampered pest suppression. At the same time, the effects of these factors on vertebrate predators and their contribution to pest control are relatively understudied, especially in European permanent crops. Using exclosures in Hungarian vineyards, we investigated the effect of birds and bats on arthropods affecting ecosystem functions and crop yield considering the local management (organic vs. integrated pest management [IPM]) and contrasting landscape heterogeneity of the plantations. We also collected abundance data of the European grapevine moth (Lobesia botrana) and canopy-dwelling herbivorous and predatory arthropods and quantified fruit and leaf damage and sentinel prey predation associated with these groups. As opposed to summer bat activity, forested and connected landscapes promoted high insectivorous bird abundance and bat activity in spring and contributed to lower fruit damage caused by L. botrana. Vineyard management showed no effect on birds and bats. In contrast, canopy-dwelling arthropod density was higher in organic than in IPM vineyards, resulting in higher leaf herbivory and the occurrence of caterpillar predation there. Bird and bat exclusion increased leaf herbivory and fruit damage, leading to higher yields in control plots. Furthermore, increased bat activity significantly decreased the abundance of the major grape pest, L. botrana, in spring. Synthesis and applications. Our results highlight the importance of bats and birds in reducing herbivory and increasing economic benefits in vineyards. Their presence and foraging activity can be promoted by connected landscapes incorporating hedgerows and small groups of trees as well as native, deciduous forest patches that can potentially increase the amount of food sources and suitable nesting and roosting sites. Organic vineyards in these landscapes can further enhance pest control services by supporting predatory arthropods

Costing conservation: an expert appraisal of the pollinator habitat benefits of England’s entry level stewardship

Pollination services provided by insects play a key role in English crop production and wider ecology. Despite growing evidence of the negative effects of habitat loss on pollinator populations, limited policy support is available to reverse this pressure. One measure that may provide beneficial habitat to pollinators is England’s entry level stewardship agri-environment scheme. This study uses a novel expert survey to develop weights for a range of models which adjust the balance of Entry Level Stewardship options within the current area of spending. The annual costs of establishing and maintaining these option compositions were estimated at £59.3–£12.4 M above current expenditure. Although this produced substantial reduction in private cost:benefit ratios, the benefits of the scheme to pollinator habitat rose by 7–140 %; significantly increasing the public cost:benefit ratio. This study demonstrates that the scheme has significant untapped potential to provide good quality habitat for pollinators across England, even within existing expenditure. The findings should open debate on the costs and benefits of specific entry level stewardship management options and how these can be enhanced to benefit both participants and biodiversity more equitably

Crop pests and predators exhibit inconsistent responses to surrounding landscape composition

The idea that noncrop habitat enhances pest control and represents a win–win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win–win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies

Pheromones and Other Semiochemicals for Monitoring Rare and Endangered Species

As global biodiversity declines, biodiversity and conservation have become ever more important research topics. Research in chemical ecology for conservation purposes has not adapted to address this need. During the last 10-15 years, only a few insect pheromones have been developed for biodiversity and conservation studies, including the identification and application of pheromones specifically for population monitoring. These investigations, supplemented with our knowledge from decades of studying pest insects, demonstrate that monitoring with pheromones and other semiochemicals can be applied widely for conservation of rare and threatened insects. Here, I summarize ongoing conservation research, and outline potential applications of chemical ecology and pheromone-based monitoring to studies of insect biodiversity and conservation research. Such applications include monitoring of insect population dynamics and distribution changes, including delineation of current ranges, the tracking of range expansions and contractions, and determination of their underlying causes. Sensitive and selective monitoring systems can further elucidate the importance of insect dispersal and landscape movements for conservation. Pheromone-based monitoring of indicator species will also be useful in identifying biodiversity hotspots, and in characterizing general changes in biodiversity in response to landscape, climatic, or other environmental changes