363 research outputs found

    Are roads refuges or barriers for small mammals? Implications for road verge management

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    Roads are often considered barriers to animal movement thereby reducing the persistence of species in their vicinity. Nonetheless, road verges may provide refuges or corridors for small mammals across highly human-modified landscapes. In these landscapes, road verges can be the last remnants of suitable habitats. However, in well-preserved habitats, road verges may show a similar vegetation structure to surrounding areas. In these circumstances, the effects of roads, road verges and roadside management on smallmammal conservation are still not clearly understood. These effects are expected to depend on management practices on road surrounding land. This thesis aims to assess the effects of roads on demographic traits, movements patterns and landscape connectivity for small mammals in a well-preserved agro-silvo pastoral system. Populations of wood mice (Apodemus sylvaticus) were studied using capture-mark-recapture methods in a road area and in a similar roadless area. Extended Pollock’s robust design models were used to assess several population parameters. Movement patterns were evaluated by step analysis. Graph theory was used to quantify landscape connectivity. Road and roadside management decreased abundance and body condition, hampered road crossings, changed movement direction, and decreased overall landscape connectivity for wood mice. Road verges provided habitat and pathways, promoting functional connectivity for this species in the road area. Nevertheless, road verges’ role depended on the vegetation management on verges and surrounding areas. The recommendations suggested in this work for roadside vegetation management also account for the potential increase in roadkill and fire risk. The outcomes of this thesis emphasize the importance of properly managing vegetation on road verges and surrounding private land for the conservation of small mammals in well-preserved habitats; - As estradas são refúgios ou barreiras para os pequenos mamíferos? Implicações para a gestão das bermas de estrada - Resumo: As estradas podem ser barreiras ao movimento dos animais reduzindo a persistência das espécies na sua vizinhança. No entanto, as bermas de estrada podem oferecer refúgios ou corredores para pequenos mamíferos em paisagens altamente modificadas. Nestas paisagens, as bermas podem ser os últimos redutos de habitat favorável. Contudo, em habitats bem-preservados, as bermas de estrada podem ter uma estrutura de vegetação semelhante às áreas circundantes. Assim, os efeitos nos pequenos mamíferos das estradas, das bermas e da sua gestão permanecem por clarificar. Estes efeitos dependerão da gestão na área circundante à estrada. Esta tese pretende avaliar os efeitos das estradas nos parâmetros populacionais, padrões de movimento e conectividade da paisagem para pequenos mamíferos num sistema agro-silvo-pastoril bem-preservado. As populações de rato-do-campo (Apodemus sylvaticus) foram estudadas através de captura-marcação recaptura numa área com estrada e numa área semelhante sem estrada. Vários parâmetros populacionais foram avaliados usando modelos de desenho robusto de Pollock. Os padrões de movimento foram analisados com base em etapas de movimento. A teoria dos grafos serviu de base para a quantificação da conectividade da paisagem. A estrada e a gestão das bermas diminuíram a abundância e a condição corporal, dificultaram os atravessamentos da estrada, alteraram a direcção do movimento, e diminuíram a conectividade para o rato-do-campo. As bermas de estrada proporcionaram habitat e caminhos, promovendo a conectividade funcional da área para esta espécie. No entanto, o papel das bermas de estrada dependeu da gestão da vegetação nas bermas e na área circundante. As recomendações sugeridas neste trabalho para a gestão das bermas de estrada têm em consideração os riscos de atropelamento e de incêndio. Os resultados desta tese realçam a importância de uma gestão adequada da vegetação nas bermas de estrada e propriedades privadas circundantes para a conservação de pequenos mamíferos em habitats bem-preservados

    Assessing the health status of managed honeybee colonies (HEALTHY-B): a toolbox to facilitate harmonised data collection

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    Tools are provided to assess the health status of managed honeybee colonies by facilitating further harmonisation of data collection and reporting, design of field surveys across the European Union (EU) and analysis of data on bee health. The toolbox is based on characteristics of a healthy managed honeybee colony: an adequate size, demographic structure and behaviour; an adequate production of bee products (both in relation to the annual life cycle of the colony and the geographical location); and provision of pollination services. The attributes ‘queen presence and performance’, ‘demography of the colony’, ‘in-hive products’ and ‘disease, infection and infestation’ could be directly measured in field conditions across the EU, whereas ‘behaviour and physiology’ is mainly assessed through experimental studies. Analysing the resource providing unit, in particular land cover/use, of a honeybee colony is very important when assessing its health status, but tools are currently lacking that could be used at apiary level in field surveys across the EU. Data on ‘beekeeping management practices’ and ‘environmental drivers’ can be collected via questionnaires and available databases, respectively. The capacity to provide pollination services is regarded as an indication of a healthy colony, but it is assessed only in relation to the provision of honey because technical limitations hamper the assessment of pollination as regulating service (e.g. to pollinate wild plants) in field surveys across the EU. Integrating multiple attributes of honeybee health, for instance, via a Health Status Index, is required to support a holistic assessment. Examples are provided on how the toolbox could be used by different stakeholders. Continued interaction between the Member State organisations, the EU Reference Laboratory and EFSA is required to further validate methods and facilitate the efficient use of precise and accurate bee health data that are collected by many initiatives throughout the EU

    Towards a sustainable rural mountain landscape : exploring the (hi)stories of Val Borbera (Northern Apennines, Italy)

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    The landscape ecology of butterflies in traditionally managed Norwegian farmland

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    The modernisation of agriculture has lead to changes in Norwegian farming landscapes that have consequences for butterfly distribution and abundance. Particularly important is the abandonment of traditionally managed grasslands and the consequent increase in potential barriers of scrub and trees in the landscape. In this thesis I use a landscape ecological perspective to explore the effects of abandonment on butterfly dispersal. I demonstrate that landscape elements influence butterfly movement behaviour: tall structures were significant barriers for a range of species and even low features, such as roads, elicited significant behavioural responses which shaped the movement patterns of butterflies. Behavioural differences between species were related to ecological and physiological characteristics. Movement patterns of Scarce Coppers (Lyceana virgaureae) were recorded by mark-release- recapture (MRR) techniques. Of 1711 recorded displacements, over 90 % were under 150 m. Exchange rates between meadows were dependent upon distance and the structure of intervening vegetation. A simple spatial model, parameterised with data from the behavioural experiments, was validated using MRR observations. This confirmed that the behaviour of individuals responding to single landscape elements has consequences at the level of populations and entire landscapes. The life history and movement behaviour of the endangered Apollo (Parnassius apollo), were examined using MRR. The butterfly is well adapted to a mosaic landscape structure; however, inter-meadow movement declined exponentially with increasing distance between meadows. Abandonment of hay meadows on steep slopes, with consequent forest succession, will adversely affect the Apollo by increasing the distances between open habitat. Genetic analyses support the findings of MMR studies and add a wider spatial and temporal perspective. As a conservation management priority, I recommend population mapping to identify key sites in regional networks of populations. Finally, I consider the links between empirical studies, modelling and the practical application of theory, and discuss the implications of landscape change for the butterflies of Norwegian farmland

    A Contemporary Decennial Examination of Changing Agricultural Field Sizes Using Landsat Time Series Data

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    Field size distributions and their changes have not been studied over large areas as field size change datasets are not available. This study quantifies agricultural field size changes in a consistent manner using Landsat satellite data that also provide geographic context for the observed decadal scale changes. Growing season cloud-free Landsat 30 m resolution images acquired from 9 to 25 years apart were used to extract field object classifications at seven sites located by examination of a global agricultural yield map, agricultural production statistics, literature review, and analysis of the imagery in the US Landsat archive. High spatial resolution data were used to illustrate issues identifying small fields that are not reliably discernible at 30 m Landsat resolution. The predominant driver of field size change was attributed by literature review. Significant field size changes were driven by different factors, including technological advancements (Argentina and USA), government land use and agricultural policies (Malaysia, Brazil, France), and political changes (Albania and Zimbabwe). While observed local field size changes were complex, the reported results suggest that median field sizes are increasing due to technological advancements and changes to government policy, but may decrease where abrupt political changes affect the agricultural sector and where pastures are converted to arable land uses. In the limited sample considered, median field sizes increased from 45% (France) to 159% (Argentina) and decreased from 47% (Brazil) to 86% (Albania). These changes imply significant impacts on landscape spatial configuration and land use diversity with ecological and biogeochemical consequences

    Nesting Ecology, Management and Population Genetics of Bumblebees: An Integrated Approach to the Conservation of an Endangered Pollinator Taxon

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    Bumblebees have shown both long and short-term declines throughout their range. These declines may be attributed to a range of factors including changes in land use, alterations in climatic conditions and species introductions. However, management strategies for bumblebee conservation often focus on provision of summer forage resources and other factors are frequently overlooked. Provision of spring forage and nesting sites for bumblebee queens are rarely considered, though colony foundation and early colony growth are two of the most sensitive stages in bumblebee life history. Here, the efficacy of certain agri-environment prescriptions for providing spring forage and nest sites for bumblebees is assessed, highlighting a need for specific schemes targeted towards the provision of these vital resources in the rural environment. The nesting ecology of bumblebees is poorly understood because wild colonies are difficult to locate. However, a greater knowledge of the colony-level effects of environmental change is crucial to understanding bumblebee declines. Attracting bumblebee queens to nest in artificial domiciles could provide a valuable tool for studying colony-level responses. However, domicile trials and the findings of a literature review presented here demonstrate that this approach may be largely impractical for use in the UK. Conversely, a nationwide public bumblebee nest survey produced numerous data regarding nest site preferences among bumblebee species and also demonstrated that citizen science may also provide a sensitive method for detecting declines in currently common bumblebee species. An understanding of the ecology of species interactions and coexistence can provide valuable insights into factors that may influence declines. Data presented here suggest that coexistence between some bumblebee species may be maintained by resource partitioning based on diel activity patterns that are linked to species-specific environmental tolerances. If this is the case, the potential role of climate change in bumblebee declines may be severely underestimated. There is also increasing evidence that genetic factors may play a role in bumblebee losses, accelerating declines of small, fragmented populations as a result of reduction in genetic diversity and inbreeding depression. Here, the feasibility of reintroducing British B. subterraneus (now extinct in the UK) from New Zealand into England is assessed using population genetic techniques. The findings suggest that the population history of B. subterraneus in New Zealand has resulted in a dramatic loss of genetic diversity and high genetic divergence from the original UK population, suggesting that it may not be a suitable for use in the reintroduction attempt. This work draws together some understudied aspects of bumblebee ecology with a particular focus on nest site requirements, availability of spring forage, mechanisms of avoidance of inter-specific competition and population genetic processes. The potential role of these in bumblebee declines is considered and new data relevant to the conservation of these important species is presented. It is hoped that this work will inform future management strategies for bumblebee conservation, highlight areas in need of further study and provide a sound starting point for future research in these areas

    Glastir Monitoring & Evaluation Programme. Second year annual report

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    What is the purpose of Glastir Monitoring and Evaluation Programme? Glastir is the main scheme by which the Welsh Government pays for environmental goods and services whilst the Glastir Monitoring and Evaluation Programme (GMEP) evaluates the scheme’s success. Commissioning of the monitoring programme in parallel with the launch of the Glastir scheme provides fast feedback and means payments can be modified to increase effectiveness. The Glastir scheme is jointly funded by the Welsh Government (through the Rural Development Plan) and the EU. GMEP will also support a wide range of other national and international reporting requirements. What is the GMEP approach? GMEP collects evidence for the 6 intended outcomes from the Glastir scheme which are focussed on climate change, water and soil quality, biodiversity, landscape, access and historic environment, woodland creation and management. Activities include; a national rolling monitoring programme of 1km squares; new analysis of long term data from other schemes combining with GMEP data where possible; modelling to estimate future outcomes so that adjustments can be made to maximise impact of payments; surveys to assess wider socio-economic benefits; and development of novel technologies to increase detection and efficiency of future assessments. How has GMEP progressed in this 2nd year? 90 GMEP squares were surveyed in Year 2 to add to the 60 completed in Year 1 resulting in 50% of the 300 GMEP survey squares now being completed. Squares will be revisited on a 4 year cycle providing evidence of change in response to Glastir and other pressures such as changing economics of the farm business, climate change and air pollution. This first survey cycle collects the baseline against which future changes will be assessed. This is important as GMEP work this year has demonstrated land coming into the scheme is different in some respects to land outside the scheme. Therefore, future analysis to detect impact of Glastir will be made both against the national backdrop from land outside the scheme and this baseline data from land in scheme. A wide range of analyses of longterm data has been completed for all Glastir Outcomes with the exception of landscape quality and historic features condition for which limited data is available. This has involved combining data with 2013/14 GMEP data when methods allow. Overall analysis of long term data indicates one of stability but with little evidence of improvement with the exception of headwater quality, greenhouse gas emissions and woodland area for which there has been improvement over the last 20 years. Some headline statistics include: 51% of historic features in excellent or sound condition; two thirds of public rights of way fully open and accessible; improvement in hedgerow management with 85% surveyed cut in the last 3 years but < 1% recently planted; 91% of streams had some level of modification but 60% retained good ecological quality; no change topsoil carbon content over last 25 years. What is innovative? GMEP has developed various new metrics to allow for more streamlined reporting in the future. For example a new Priority Bird species Index for Wales which combines data from 35 species indicates at least half have stable or increasing populations. The new GMEP Visual Quality Landscape Index has been tested involving over 2600 respondents. Results have demonstrated its value as an objective and repeatable method for quantifying change in visual landscape quality. A new unified peat map for Wales has been developed which has been passed to Glastir Contract Managers to improve targeting of payments when negotiating Glastir contracts. An estimate of peat soil contribution to current greenhouse gas emissions due to human modification has been calculated. Models have allowed quantification of land area helping to mitigate rainfall runoff. We are using new molecular tools to explore the effects of Glastir on soil organisms and satellite technologies to quantify e.g. small woody features and landcover change. Finally we are using a community approach to develop a consensus on how to define and report change in High Nature Value Farmland which will be reported in the Year 3 GMEP report

    Book of abstracts, 4th World Congress on Agroforestry

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