•Pond management increases species richness and abundance of visiting farmland birds.•Managed ponds support a number of UK conservation priority species.•Non-managed ponds chiefly support woodland ...bird assemblages.•A mosaic approach to pond management appears to optimize farmland bird use.
Biodiversity declines in agricultural landscapes represent a major conservation challenge. In the UK, some agricultural landscapes contain high pond densities, but many farmland ponds have become terrestrialised since the 1960s, with input of organic material resulting in a decrease in the size and depth of ponds that eventually transform into wet woodland habitats. Pond management, including removal of overhanging scrub and sediment, has proven highly effective in enhancing freshwater biodiversity. However, the implications of this management for farmland bird assemblages are unknown.
Bird surveys were undertaken at recently managed, open, macrophyte-dominated and at highly terrestrialised, macrophyte-free ponds in the intensively cultivated farmland of North Norfolk, UK. The diversity, abundance and composition of bird assemblages visiting these ponds were compared to determine responses to pond management by tree and mud removal.
Avian species richness, abundance and bird-visit frequencies were all higher at open farmland ponds. The observed patterns of bird occurrence were best explained by management-induced reductions in tree shading that resulted in aquatic macrophyte-dominance likely associated with high emergent invertebrate prey abundance. Moreover, we predict that open-canopy ponds offer greater habitat heterogeneity than overgrown ponds, allowing diversified bird use. Overgrown, terrestrialised ponds were preferred by some woodland bird species. Gamma diversity across the entire pondscape exceeded all individual pond alpha diversity measures by an order of magnitude, suggesting distinct variation in the bird assemblages visiting farmland ponds during different successional stages.
Pond management that generates a mosaic of pond successional stages, including open-canopy, macrophyte-dominated ponds, could help to address the long-term decline of farmland birds. We strongly advocate increased agro-ecological research in this field, combined with greater emphasis on ponds and pond management options in agri-environment schemes.
•Realised ES are a product of the potential service and specified beneficiaries.•Natural capital (NC) and human-derived capital (HDC) are both essential for ES.•HDC plays a role even at the stage of ...potential ecosystem services.•It is possible but not always easy to separate the contribution of NC and HDC to ES.•Sustainable management should identify critical NC and HDC for each service.
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There is growing interest in the role that natural capital plays in underpinning ecosystem services. Yet, there remain differences and inconsistencies in the conceptualisation of capital and ecosystem services and the role that humans play in their delivery. Using worked examples in a stocks and flows systems approach, we show that both natural capital (NC) and human-derived (produced, human, social, cultural, financial) capital (HDC) are necessary to create ecosystem services at many levels. HDC plays a role at three stages of ecosystem service delivery. Firstly, as essential elements of a combined social-ecological system to create a potential ecosystem service. Secondly, through the beneficiaries in shaping the demand for that service. Thirdly, in the form of additional capital required to realise the ecosystem service flow. We show that it is possible, although not always easy, to separately identify how these forms of capital contribute to ecosystem service flow. We discuss how applying a systems approach can help identify critical natural capital and critical human-derived capital to guide sustainable management of the stocks and flows of all forms of capital which underpin provision of multiple ecosystem services. The amount of realised ecosystem service can be managed in several ways: via the NC & HDC which govern the potential service, and via factors which govern both the demand from the beneficiaries, and the efficiency of use of the potential service by those beneficiaries.
Agri-environment schemes (AES) are key mechanisms to deliver conservation policy, and include management to provide resources for target taxa. Mobile species may move to areas where resources are ...increased, without this necessarily having an effect across the wider countryside or on populations over time. Most assessments of AES efficacy have been at small spatial scales, over short timescales, and shown varying results. We developed a survey design based on orthogonal gradients of AES management at local and landscape scales, which will enable the response of several taxa to be monitored. An evidence review of management effects on butterflies, birds and pollinating insects provided data to score AES options. Predicted gradients were calculated using AES uptake, weighted by the evidence scores. Predicted AES gradients for each taxon correlated strongly, and with the average gradient across taxa, supporting the co-location of surveys across different taxa.
Nine 1 × 1 km survey squares were selected in each of four regional blocks with broadly homogenous background habitat characteristics. Squares in each block covered orthogonal contrasts across the range of AES gradients at local and landscape scales. This allows the effects of AES on species at each scale, and the interaction between scales, to be tested. AES options and broad habitats were mapped in field surveys, to verify predicted gradients which were based on AES option uptake data. The verified AES gradient had a strong positive relationship with the predicted gradient. AES gradients were broadly independent of background habitat within each block, likely allowing AES effects to be distinguished from potential effects of other habitat variables. Surveys of several mobile taxa are ongoing.
This design will allow mobile taxa responses to AES to be tested in the surrounding countryside, as well as on land under AES management, and potentially in terms of population change over time. The design developed here provides a novel, pseudo-experimental approach for assessing the response of mobile species to gradients of management at two spatial scales. A similar design process could be applied in other regions that require a standardized approach to monitoring the impacts of management interventions on target taxa at landscape scales, if equivalent spatial data are available.
•Agri-environment schemes (AES) are key conservation policies in many countries.•A novel design was developed to monitor mobile taxa responses to AES at two scales.•Survey sites covered orthogonal contrasts across local and landscape AES gradients.•These AES gradients are independent of other background habitat variables.•This novel design monitors habitat management effects at varying spatial scales. .
Background. Developing histological prediction models that estimate the probability of developing metastatic deposit will help clinicians to identify individuals who need either radical or ...prophylactic neck dissection, which leads to better prognosis. Identification of accurate predictive models in oral cancer is important to overcome extensive prophylactic surgical management for neck nodes. Therefore, accurate prediction of metastasis in oral cancer would have an immediate clinical impact, especially to avoid unnecessary radical treatment of patients who are at a low risk of metastasis. Methods. Histologically confirmed OSCC cases with neck dissection were used. Interrelation of demographic, clinical, and histological data was done using univariate and multivariate analysis. Results. 465 cases were used and presence of metastasis and extracapsular invasion were statistically well correlated with level of differentiation (p<0.001) and pattern of invasion (p<0.001). Multivariate analysis showed level of differentiation, pattern of invasion, and stage as predictors of metastasis. Conclusions. The proposed predictive model may provide some guidance for maxillofacial surgeons to decide the appropriate treatment plan for OSCC, especially in developing countries. This model appears to be reliable and simple and may guide surgeons in planning surgical management of neck nodes.
Knowledge of the direction, magnitude, and timing of changes in bird population abundance is essential to enable species of priority conservation concern to be identified, and reasons for the ...population changes to be understood. We give a brief review of previous techniques for the analysis of large-scale survey data and present a new approach based on generalized additive models (GAMs). GAMs are used to model trend as a smooth, nonlinear function of time, and they provide a framework for testing the statistical significance of changes in abundance. In addition, the second derivatives of the modeled trend curve may be used to identify key years in which the direction of the population trajectory was seen to change significantly. The inclusion of covariates into models for population abundance is also discussed and illustrated, and tests for the significance of covariate terms are given. We apply the methods to data from the Common Birds Census of the British Trust for Ornithology for 13 species of farmland birds. Seven of the species are shown to have experienced statistically significant declines since the mid-1960s. Two species exhibited a significant increase. The population trajectories of all but three species turned downward in the 1970s, although in most cases the 1980s brought either some recovery or a decrease in the rate of decline. The majority of populations have remained relatively stable in the 1990s. The results are comparable with those from other analysis techniques, although the new approach is shown to have advantages in generality and precision. We suggest extensions of the methods and make recommendations for the design of future surveys.
Since 2013, the Department for Environment, Food and Rural Affairs (Defra) has licenced culling of European badger (Meles meles) populations in several English regions. In the first 7 years, more ...than 100 000 badgers have been removed. It is critical to evaluate the ecological impact of severely depressing the population of a widespread predator from large areas of the country, such as effects on breeding bird populations. Citizen science survey data on the abundance of breeding birds supports the estimation of population trends, i.e. whether species are exhibiting population growth or declines, and the effects of potential environmental influences, such as badger removal, on these trends. Here, these survey data are used together with data on the presence and amount of culling in an area to explore whether removing badgers has an effect on breeding bird populations both inside and outside culling zones from 2013–2019. This is not equivalent to a controlled trial, but collects critical, landscape‐scale evidence in real‐world conditions. In analyses evaluating the effect of culling presence, 18 of 55 bird species showed significant or near‐significant growth rate changes. Of these, four species had higher growth rates and 14 exhibited lower growth rates in cull areas, compared to areas outside of the culling zones. When using culling intensity data to assess the impact on growth rates, 10 of 55 species showed significant or near‐significant results, with only one species exhibiting a higher population growth rate in the presence of more intensive culling. Predicted sensitivity to badger effects based on species' ecologies did not predict whether the measured relationships were significant, or their directions, suggesting that other factors underlie the patterns seen. Hence, there was little evidence to indicate consistent, community‐level effects of badger removal on bird populations. A landscape‐scale, quasi‐experimental approach is strongly recommended to provide stronger inference about the complex potential ecological effects of culling predators such as the badger.
It is critical to evaluate the ecological impact of depressing the population of widespread predators from large areas of countryside and government‐licensed culling of badger populations in several English regions has removed more than 100 000 badgers in seven years. Here, citizen science survey data and badger culling information are used to explore whether removing badgers had an effect on breeding bird populations from 2013 to 2019; although not equivalent to a controlled trial, the analyses accounted for landscape‐scale habitat variation. Overall, we found little evidence to indicate consistent, community‐level effects of badger removal on breeding bird populations, including on species that nest on or near to the ground, although evidence of both positive and negative associations was detected.
1. Widespread declines in the populations of many British farmland birds have occurred since the early 1970s. We must understand the causes of these declines to make recommendations about ...conservation and agricultural management, and this can be approached by investigating the relationships, across species, between abundance and agricultural change. We describe novel, quantitative approaches to the interpretation of abundance indices from which reliable inferences about conservation status can be made. 2. We calculated farmland Common Birds Census indices for 42 species, smoothed the series to reveal underlying trends and estimated confidence intervals for the changes in abundance. 3. Between 1968 and 1995, the abundance of 12 species declined significantly and that of 14 species increased. 4. Specialization was the only significant determinant of changes in abundance (of 10 tests against species characteristics): 13 farmland specialists declined, on average, by 30%, whilst 29 more generalist species underwent an average increase of 23%, confirming that farmland birds should engender conservation concern. 5. Smoothed abundance curves, transformed to emphasize trend direction and timing, were then compared quantitatively to identify whether groups of species had shared common trends. 6. Species tended not to be strongly grouped, but small groups of species with common trends were identified. Similarities in ecology among grouped species clarify the possible environmental causes of their population trends, indicating future research priorities. 7. The groups identified included: one group consisting of three thrush species Turdus and the skylark Alauda arvensis L. which all declined from the mid-1970s after being stable previously; one group comprising three trans-Saharan migrant warblers (Sylvidae), whose abundance fell in the early 1970s and later increased; and a diverse group of six smoothly increasing species. 8. Turning points were identified as where each species' population trend turned significantly, revealing critical periods during which populations are likely to have been affected by environmental change. 9. Three collections of downward turning points were found, including one in the mid-1970s when many farmland bird declines began. Four other periods each included many upturns. The groups of turning points should facilitate the identification of environmental changes which have had widespread effects. Management prescriptions can then be designed to reverse or to mirror such key changes and thereby focus conservation effort effectively.
1. Changes in agriculture have been linked to widespread declines in farmland bird populations. One approach to the identification of the causes of observed population changes is to investigate ...historical changes in national demographic rates. 2. We analysed the British Trust for Ornithology's nest records database to investigate whether long-term farmland population trends could have been driven by changes in several components of the annual breeding performance of 12 granivorous bird species. Clutch size, brood size, chick: egg ratio and daily nest failure rates were analysed with respect to blocks of years during which abundance (as measured by the Common Birds Census) was increasing, stable or declining. The individual components of breeding performance were combined to provide estimates of the production of fledglings per breeding attempt. 3. Most species' population declines were not associated with poor breeding performance per attempt. Effects of environmental change on this parameter therefore cannot be a general mechanism behind the major population declines seen. 4. A fall in linnet Carduelis cannabina fledgling production per attempt, driven primarily by increased nest failure rates during the egg period, represented the strongest evidence for an important effect of breeding performance on abundance. This change could have driven the principal population decline (1975-86) for this species. 5. Conversely, at least for the declining turtle dove Streptopelia turtur, skylark Alauda arvensis, tree sparrow Passer montanus, yellowhammer Emberiza citrinella and corn bunting Miliaria calandra, breeding performance per attempt was higher while populations declined. 6. Variation in annual survival and fledgling production per breeding attempt alone could not explain changes in abundance for at least seven species. This may suggest that changes in post-fledging survival rates and/or the number of breeding attempts per year could have been important. 7. Management to improve over-winter survival may be critical in reversing the population trends of most declining species, but such management might still best be directed at the breeding season. Post-fledging survival rates and the number of breeding attempts made within a season are little-studied demographic variables that are high priorities for future research and long-term monitoring.
Nodal metastasis is a major prognostic indicator for oral squamous cell carcinoma (OSCC) progression. Recently, it has been revealed that lymphangiogenic growth factor VEGF-C and its receptor Flt-4 ...play an important role for invasion and metastasis in cancer cells.
To examine VEGF-C expression and its correlation with lymphatic status, including the number of lymph vessels and lymphatic invasion, tumour invasion and metastasis in OSCC.
Intratumoural and peritumoural lymphatic vessels were examined using D2-40 in 54 OSCC cases and correlated with VEGF-C expression and clinicopathological findings. The histological pattern of invasion and pathological findings were compared.
High expression of VEGF-C was frequently observed in OSCC and was associated with increased number of lymph vessels and lymphatic invasion. VEGF-C was well correlated with invasion pattern and metastasis.
Results suggest that VEGF-C may play an important role for lymphangiogenesis and invasion in the metastatic process and can be a strong predicting factor for metastasis of OSCC.
1. The reed bunting Emberiza schoeniclus is one of a suite of granivorous farmland bird species that suffered a major population decline in Britain during the late 1970s and early 1980s. Extensive ...monitoring data indicate a large increase in the abundance of reed buntings between 1963 and 1975, followed by a decline of 58% on farmland and 66% along linear waterways during the period 1975-83. Since 1983 numbers have remained relatively stable in both habitats. 2. During the population decline, breeding numbers declined rapidly on arable and mixed farms, but remained relatively stable on pastoral farms. The decline on farmland was greater in northern Britain than in the south-east. 3. Extensive nest recording indicated that breeding performance was higher during the period of population decline (2.74 young per nesting attempt) than during the preceding period of population increase (2.65) or the recent period of population stability (2.17). 4. Minimum survival during the first year of life (estimated from mark-recapture data) declined during the 1970s and early 1980s, and increased strongly during the 1990s. The trend in first-year survival was independent of a weak positive relationship with winter temperature. Although there was evidence of a similar temporal trend in adult survival, this disappeared when winter temperature was taken into account. 5. A demographic model indicated that the timing and magnitude of the observed changes in first-year survival and adult survival were each sufficient alone to account for the observed changes in the abundance of reed buntings during the period 1969-87. A reduction in over-winter survival was probably the main demographic cause of the reed bunting population decline, although loss of breeding habitat and a recent reduction in breeding performance may also have influenced numbers. 6. During winter reed buntings feed mainly on small grass and weed seeds. The observed declines in abundance and survival rates coincide with the widespread introduction of a range of efficient herbicides and the loss of winter stubbles from British farmland. Our findings are therefore consistent with the hypothesis that the decline of the British reed bunting population was caused primarily by a reduction in food availability outside the breeding season. Changes in agricultural practices that increase the abundance of small weed and grass seed on farmland during winter are likely to allow at least a partial recovery of the British reed bunting population.
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