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• Opportunistic citizen science is valuable for biodiversity trend analysis. • Participants in citizen science vary in their recording behaviour. • Estimated trends in occupancy were robust to differences in recorder behaviour. • Species occupancy itself was more sensitive to some aspects of recorder behaviour. Opportunistic species sightings submitted by citizen science volunteers are a valuable source of species data for trends analysis, as used in biodiversity indicators. However, projects collecting these data give people flexibility where and when to make records, and the recording behaviour of participants varies between individuals. Here we tested the effect of recorder behaviour on outputs of the analysis of temporal biodiversity trends. Using a large (c. 3 million records), 20 year unstructured citizen science dataset of butterfly records in Great Britain, we manipulated recorder behaviour by constructing biased 50% subsamples of the dataset by preferentially including different types of recorders (based on high and low values of four metrics independently describing the temporal, spatial and taxonomic attributes of recorder behaviour). We found that, in general, the three outputs (namely: occupancy trend, precision of the trend, and the estimate of occupancy) showed relatively little deviation from random expectation across most of the different types of recorder behaviour. Occupancy trends showed least deviation, while estimates of occupancy itself showed greatest deviation from the random expectation. Regarding the recorder behaviours, the outputs were most sensitive to variation in 'recorder potential', which describes the difference between 'thorough' and 'incidental' recorders. Importantly, by demonstrating the robustness of occupancy trends to differences in recorder behaviour, this study provides support for the appropriate use of occupancy trend modelling for unstructured citizen science. However, we did not consider change in recorder behaviour over time, so further research is required to assess the impact of this on trend modelling. This study highlights the value of developing solutions to further increase the robustness of biodiversity trend analysis. These solutions should include both analytical developments and enhancements in project design to engage participants. [ABSTRACT FROM AUTHOR]

Invasive alien species, including pests and diseases of plants and animals, are a major cause of biodiversity change and may impact upon human well-being and the economy. If new, potentially invasive, taxa arrive then it is most cost-effective to respond as early in their establishment as possible. Information to support this can be gained from volunteers, i.e. via citizen science. However, it is vital to develop ways of quantifying volunteer recorder effort to assess its contribution to the detection of rare events, such as the arrival of invasive alien species. We considered the potential to detect adult oak processionary moths ( Thaumetopoea processionea ) by amateur naturalists recording moths at light traps. We calculated detection rates from the Netherlands, where T. processionea is widely established and poses a risk to tree health and human health, and applied these to the spatial pattern of moth recording effort in the UK. The probability of recording T. processionea in the Netherlands varied across provinces from 0.05–2.4% per species of macro-moth recorded on a list of species (so equalling 1–52% for a list of 30 species). Applying these rates to the pattern of moth recording in the UK: T. processionea could be detected (detection > 0%), if it were present, in 69% and 4.7% of 10 km and 1 km squares, respectively. However, in most squares detection probability is low (< 1% of 1 km squares have annual detection probability of > 10%). Our study provides a means to objectively assess the use of citizen science as a monitoring tool in the detection of rare events, e.g. the arrival of invasive alien species, occurrence of rare species and natural colonisation. [ABSTRACT FROM AUTHOR]

Abstract: Whilst considerable research effort in Europe has linked agricultural intensification with dramatic declines of seed-feeding birds, surprisingly little is known about the wider importance of seeds in animal food-webs. Moreover, understanding the dynamics of farmland seed food resources for species of conservation concern is of considerable research interest. We examined the distribution of berries and soil-surface seeds in the managed and unmanaged habitats of a 125ha organic farm. We took soil suction-samples over a year, counted and identified all seeds, and compared abundances and species-richness between habitats. We constructed ecological networks from literature records and by rearing insects to investigate the importance of these seeds for insects, birds and mammals. We predicted the impacts of management on seed biomass, energy and the ecosystem service of pest control across the whole farm. We estimated seed and berry food resources of up to 33metric tons of biomass and 560GJ of energy on the farm. Potentially, more than 330 species use the seeds as a food resource, the overwhelming majority of which are invertebrates (82%) relying predominantly on non-crop and weed species. Generally, uncultivated semi-natural habitats such as woodland and mature hedgerows were more species-rich and had higher seed biomass and energy than crop habitats throughout the year, but fallow land was disproportionately important for seeds during the summer. Models of increased management intensity revealed declines of up to 19% in seed biomass and energy and cascades through the network that resulted in a substantial decrease in potentially pest-controlling parasitoids. [Copyright &y& Elsevier]

Abstract: Hair tubes are efficient for sampling shrews and potentially important for sampling Sorex minutus, which is poorly sampled with other methods such as live trapping. We tested the effect of aperture size, bait, and position and type of sticky strip in hair tubes on the detection of S. minutus hairs. The optimum S. minutus hair tube design has high specificity for S. minutus (hairs are 12 times more likely to be from S. minutus than from other species), easily constructed and suitable for use in large-scale surveys. Between the end of July and middle of September 2008 we repeatedly surveyed 46 sites twice with a transect of 20 S. minutus hair tubes. Occupancy of S. minutus was higher in hedgerow sites (0.92) than grassland (0.59) and woodland sites (0.42). Relative activity-density was estimated from models allowing abundance-induced heterogeneity in detection probability and was also higher in hedgerow sites (1.75) than grassland (1.23) and woodland sites (0.72). Relative activity-density is a function of abundance and movement and hence should be interpreted with caution but is a valuable parameter to estimate from data on presence or absence of a species at a site. From our data we recommend that surveys are carried before the end of August, in which case three surveys per site at up to 120 sites per habitat (depending on habitat and start date) are necessary to obtain precise estimates of site occupancy. Site occupancy should be quantified as a relevant parameter alongside abundance when conducting indirect surveys of mammals and relative activity-density should also be considered. [Copyright &y& Elsevier]

Abstract: Leaf area index (LAI; the single-sided leaf area per unit area of ground) is a measure of plant standing crop in terrestrial ecosystems and is a key parameter in meteorological, climate and hydrological models. While the LAI of individual species can be measured by destructive harvesting and LAI of whole landscapes can be estimated by remote sensing, estimates of species-specific LAI at the landscape-scale are lacking. Working on a 125ha farm in Somerset, UK during the summers of 2007 and 2008, we developed a method to identify sources of variation in total leaf area over time, between habitats and between species. We measured LAI for all vegetation types on the farm, namely: crops, unmanaged non-woody vegetation, hedgerows and trees. We used established methods to estimate LAI, mostly by gap fraction analysis with a LI-COR LAI-2000 Plant Canopy Analyzer and we divided LAI into its constituent species based on the data from field surveys. We found that the total LAI of the farm was 4.1, although this varied substantially between habitats from 3.3 for cereal fields to 8.0 for woods. Each month we measured LAI and found that, depending on the month, 61–81% of the leaf area was comprised of crop species (including grass and clover in pastures and short-term leys), 7–10% was woody vegetation and the remainder was non-woody semi-natural vegetation. We developed predictive models of LAI, based on our measurements of LAI in each habitat, and found that, for non-woody vegetation, variation in LAI was a function of vegetation type and vegetation height, while for hedgerows LAI was a function of hedge height and width. From our data and our predictive models we predicted changes in LAI due to five likely farm management scenarios. Changes that would have a huge impact on the visual landscape (loss of woods, reduction in hedge size) were predicted to have a smaller effect on farm-scale LAI than changes that would be visually more subtle (changes in vegetation length of grass fields). This type of modelling could be combined with regional land use data to predict the effect of regional agricultural changes (changes in land use or the intensity of land management) on LAI, and hence on ecosystems, biogeochemical cycling, carbon sequestration and hydrology. [Copyright &y& Elsevier]

This review evaluates direct (live-trapping) and indirect (genetic) methods to study dispersal in wild house mice (Mus musculus) and summarizes field and experimental data to examine the causes and consequences of dispersal. Commensal house mice (associated with human habitations, farms, food stores and other anthropogenic habitats) typically show lower rates of dispersal than feral house mice (living in crops, natural and semi-natural habitats). However, early claims of long-term fine-scale genetic structure in commensal house mice (due to low rates of dispersal) are not supported by recent data. Dispersal becomes obligatory when habitat conditions deteriorate, but most dispersal occurs below the local environmental carrying capacity and is due to social interactions with conspecifics. Excursions are relatively frequent and probably allow mice to assess the quality of habitats before dispersing. Young males have the greatest tendency to disperse, apparently prompted mainly by aggressive interactions with dominant males. If they do disperse, females integrate into new groups more easily than do males. Dispersing house mice risk loss of condition or death, but may gain reproductive opportunities on arrival in a new location. House mice can be transported passively as stowaways with humans; this contributes to population persistence and genetic structure at regional scales and has allowed house mice to spread world-wide. © 2005 The Linnean Society of London,Biological Journal of the Linnean Society, 2005,84, 565–583. [ABSTRACT FROM AUTHOR]

Understanding spatial variation in the structure and stability of plant–pollinator networks, and their relationship with anthropogenic drivers, is key for maintaining pollination services and mitigating declines. Constructing sufficient networks to examine patterns over large spatial scales remains challenging. Using biological records (citizen science), we constructed potential plant–pollinator networks at 10 km resolution across Great Britain, comprising all potential interactions inferred from recorded floral visitation and species co‐occurrence. We calculated network metrics (species richness, connectance, pollinator and plant generality) and adapted existing methods to assess robustness to sequences of simulated plant extinctions across multiple networks. We found positive relationships between agricultural land cover and both pollinator generality and robustness to extinctions under several extinction scenarios. Increased robustness was attributable to changes in plant community composition (fewer extinction‐prone species) and network structure (increased pollinator generality). Thus, traits enabling persistence in highly agricultural landscapes can confer robustness to potential future perturbations on plant–pollinator networks. [ABSTRACT FROM AUTHOR]

The increasing pace of climate change is an existential threat to farming continuity and biodiversity. Agricultural innovation is running too slowly but could be accelerated by a change in the agroecological narrative. A farmer-led agroecology prioritising farming continuity for biodiversity would speed up innovation and better serve science and society. [ABSTRACT FROM AUTHOR]

Social–ecological networks (SENs) represent the complex relationships between ecological and social systems and are a useful tool for analyzing and managing ecosystem services. However, mainstreaming the application of SENs in ecosystem service research has been hindered by a lack of clarity about how to match research questions to ecosystem service conceptualizations in SEN (i.e., as nodes, links, attributes, or emergent properties). Building from different disciplines, we propose a typology to represent ecosystem service in SENs and identify opportunities and challenges of using SENs in ecosystem service research. Our typology provides guidance for this growing field to improve research design and increase the breadth of questions that can be addressed with SEN to understand human–nature interdependencies in a changing world. Social–ecological networks (SENs) provide a promising approach to represent the complex ecological, social, and social–ecological relationships that influence ecosystems service supply. Ecosystem services can be represented in SENs as nodes, links, attributes, or as emergent properties of the network, each bringing distinct aspects of ecosystem services into focus to address different questions. Applications of SENs in ecosystem service research can foster: (i) understanding of the social and ecological drivers of ecosystem services; (ii) forecasting of the impacts of stressors; (iii) investigation of trade-offs between ecosystem services; and (iv) assessment of the effects of alternative management options. Ecosystem service research would benefit from a typology to conceptualize particular ecosystem services in SEN analyses and from greater clarity of when ecosystem service research can benefit from a SEN approach. [ABSTRACT FROM AUTHOR]

Abstract: Worldwide demand for food will increase dramatically in the future as global human population grows. Increasing efficiency of crop production is unlikely to be sufficient to meet the demand, presenting a long-term threat to humanity’s ‘well-being’. Knowledge of the system-level behaviour of agroecosystems, however, remains surprisingly limited, reflecting the agricultural focus on particular species. This is starting to change towards an ecosystem and network-based approach, following the recent revolution in thinking about resource use and sustainability in our other global food production industry: commercial fisheries. Agroecosystems appear to retain plasticity of ecological processes that might be manipulated for productivity and sustainability. Network structure and dynamics have substantial impacts on ecosystem performance, but evidence from agroecosystems lags behind network theory. Here, we provide an introduction to network theory and application in agroecosystems, identify network metrics for management and environmental change, and, finally, we highlight gaps in our current knowledge and key research themes. These themes include: is the structure of agroecological networks affected by sampling; how do ecosystem services ‘emerge’ empirically from ecological organization, function and network properties; how do spatial and temporal scale and resolution influence system performance; and, can network agroecology be used to design systems that maximize ecosystem services? [Copyright &y& Elsevier]