Desert locust populations, rainfall and climate change: insights from phenomenological models using gridded monthly data

Using autocorrelation analysis and autoregressive integrated moving average (ARIMA)modelling, we analysed a time series of the monthly number of 1° grid squares infested with desert locust Schistocerca gregaria swarms throughout the geographical range of the species from 1930–1987. Statistically significant first- and higher-order autocorrelations were found in the series. Although endogenous components captured much of the variance, adding rainfall data improved endogenous ARIMA models and resulted in more realistic forecasts. Using a square-root transformation for the locust data improved the fit. The models were only partially successful when accounting for the dramatic changes in abundance which may occur during locust upsurges and declines, in some cases successfully predicting these phenomena but underestimating their severity. Better fitting models were also produced when rainfall data were added to models of an equivalent series for desert locust hoppers (nymphs) that incorporated lagged data for locust swarms as independent variables, representing parent generations. The results are discussed in relation to predicting likely changes in desert locust dynamics with reference to potential effects of climate change

UK national ecosystem assessment follow-on: cultural ecosystem services and indicators

No description supplie

UK National Ecosystem Assessment Follow-on. Work package 7: Operationalising scenarios in the UK National Ecosystem Assessment Follow-on

Summary Study aims and approach An aim of the UK NEA Follow-on (UK NEAFO) is to develop and communicate the evidence base of the UK NEA and make it relevant to decision and policy making. It also provides an important opportunity for those working on scenario methods and concepts to scrutinise the role of futures thinking in the management of ecosystem services and so develop their effectiveness as decision support tools. In this study we have therefore asked: how can the UK NEA scenarios help us to understand, manage and communicate the consequences of changes in ecosystem services across all scales? There are many different understandings about what scenarios are, and what they should be used for. To clarify the issues surrounding the role of scenarios, we have approached this work from two angles. We have firstly looked at the way the storylines can support decision making processes. Secondly, we have looked at the content of the scenarios themselves and explored how through the use of models the UK NEA scenarios as products might be refined to enhance their value as analytical tools. Scenarios in Action We used the opportunity of a series of meetings with stakeholders to develop the UK NEA scenarios from a process perspective. These meetings took various forms, but throughout the main aim was to find out whether people found the scenarios sufficiently believable, challenging and relevant. In workshops organised by the scenario team in Leeds, Edinburgh and Belfast, we worked with participants on a series of tasks designed to help them immerse themselves in the scenarios and reflect on them critically. While those we worked with had many comments about the scenarios in detail, the evidence we collected from these meetings suggests that the majority of people found the scenarios to be plausible and the projections consistent. The majority also agreed with the proposition that the suite of scenarios as a whole addressed a relevant ranges of issues. We explored with the workshop participants several ways in which the storylines could be enriched, by: developing the narrative about the way people might live in the different scenario worlds; developing time-lines for the scenarios; thinking more deeply about regional and local differences; and, exploring how the scenarios would frustrate or facilitate the embedding of the ecosystem approach in decision making. We found that while all of these elements had value in terms of stimulating discussion and understanding of the scenarios, they were not needed in order to address deficiencies in the original storylines in terms of plausibility or credibility. The evidence we collected therefore suggests that the existing narratives are probably sufficient as an entry point for discussions about the future of ecosystem services in the UK. What was apparent from the observations that we made in the workshops was that it would probably be a mistake to ‘over-engineer’ or ‘over-specify’ the narratives because there needs to be room for discussion and probing. We were struck how people took the existing scenarios and found new features and ideas in them than had not been identified by in the original work. For example, in one session National Security, with its emphasis on resource efficiency, was found to be ‘greener’ than it initially looks. In another Local Stewardship was discovered to need some degree of central control and regulation to work efficiently. These kinds of discussion are evidence of the reflection, deliberation and social learning that can be promoted by using the UK NEA scenarios. UK NEAFO Work Package 7: Operationalising scenarios 7 In the workshop we organised in Belfast we found that the presentation of the scenarios could be tailored to a specific region (i.e. Northern Ireland) and, through area-specific breakout groups during the workshop, to specific localities within it. However, our experiences here emphasised the need for considerable preparation, consultation with the stakeholder community, and changing of the workshop format to make the scenarios intelligible and engaging to local stakeholders. Work on the use of the scenarios in a more explicit decision support role will be reported via the work on response options (WP8), which considered how they could be used to ‘stress-test’ policy response options. The experience gained from the work undertaken in the early stages of UK NEAFO was that the scenarios appeared to provide a suitable platform for the work, but that the stresstesting methodology needed to be refined. During the follow-on we have also interviewed policy leads in Defra, for example, to gain a better picture of policy needs, and the way scenarios might usefully serve them. Apart from the challenge of ‘relevance’ it is clear that the time needed for people to work with scenarios probably means that they are less useful to policy customers in the context of their everyday work but can be useful at a very broad and strategic level. However, there is clearly an opportunity for scenarios to be used more extensively through commissioned work. The importance of commissioned work has been emphasised during the follow-on phase by invitations to observe the work of the CAMERAS1 work in Scotland, and the Noise Study being undertaken for Defra. Both are actively using the UK NEA scenarios. The outcomes of these on-going studies will be reported elsewhere by others. Nevertheless, even though these projects are at a preliminary stage they help us better understand how scenarios can be used to communicate the consequences of changes in ecosystem services to different groups and individuals. Scenarios as products: developing the model base The UK NEA scenarios were initially used to make both qualitative and quantitative projections. The quantitative work mainly involved modelling how land cover would change under the different scenarios (Haines-Young et al. 2011). Although these data were used to make an analysis of the changes in marginal economic values for some ecosystem services during the initial phase of the UK NEA, they have not been fully exploited. At the time it was recognised that there were many gaps in our understanding of the links between land cover and ecosystem services; UK NEAFO has provided the opportunity to address some of these deficiencies. Thus in the follow-on work we have sought to extend the range of models that can be used to explore the UK NEA scenarios. The modelling work has not sought to change the scenarios fundamentally, but to enrich the insights that can be derived from exploring the differences between them in a systematic, and quantitative way. The goal, has been to extend the analysis that can be built up around the narratives and hence enrich the scenarios as ‘products’. Four topic areas were selected as the focus for this work: flood and drought risk (based on an analysis of changes in river flows), biodiversity (farmland birds), marine and cultural ecosystem services. Catchment modelling We looked at the effects of land-use change on river flows under each of the UK NEA scenarios. We modelled hydrological discharge within 34 UK catchments and calculated four hydrological indicators for each catchment: average annual discharge, flood hazard, and Q5 and Q95 (measures of the magnitude of unusually high (Q5) and unusually low (Q95) flows). For our flood hazard indicator we calculated the interval between floods of a size currently occurring every 30 years. Although we kept climate constant in the models, as we wanted to isolate the effects of land cover change, we ran them for both the high and low climate change land cover variants for each scenario. 1 A Coordinated Agenda for Marine, Environment and Rural Affairs Science, 2011-2016. http://www.scotland.gov.uk/Topics/Research/About/EBAR/CAMERASsite In general, the ‘green’ scenarios, Nature@Work and Green and Pleasant Land, as well as National Security, were associated with lower flows than currently occur (when measured using any of the four indicators). However, for a given scenario there was a great deal of variability between catchments in terms of the size and statistical significance of the differences. The magnitude of change across all scenarios and catchments ranged from -13% to 6% for average annual discharge, -14 to 7% for Q5, -24 to 27 % for Q95 and -16 to 36 years for flood hazard. Differences were particularly evident between Nature@Work and World Markets, with the latter associated with higher flows than occur currently, and the majority of the statistically significant increased flows. Some catchments showed significant changes that were different in sign between these two scenarios. Taken together, our results indicate that that in managing change a balance needs to be struck between alleviating the likelihoods of increased drought and increased flooding, depending on the likely effects of these phenomena in the catchment. Farmland birds We looked at the relationship between land use data produced during the first phase of the UK NEA and models of farmland bird populations, in 1kmx1km squares covered by the Breeding Bird Survey (BBS) and Winter Farmland Bird Survey (WFBS). We used Functional Space Models to estimate the annual population growth rate under each scenario of each of the 19 farmland bird species used to calculate the farmland bird index (Gregory et al. 2004). We used this to look at the relationship between land use under the scenarios and: i) the average population growth rate for all 19 species, and ii) a subset of 11 species showing declining population trends under current land use. Overall we found that land use change across the scenarios had relatively little impact. However, the only statistically significant change was for declining species under Green and Pleasant Land, where population growth rates became significantly more negative. We used Mechanistic Models to estimate the number of over-winter ‘bird-days’ for two types of seed-eating farmland birds, a yellowhammer-type and linnet-type These species were chosen because they differ in their food preferences with respect to cereal, oil and weed seeds, but between them are representative of the diversity of seed-eating farmland birds as a whole. We found a significant decline in the ecological value of lowland agricultural areas for these species across all UK NEA scenarios, but the greatest impact was for scenarios with the highest monetised values for ecosystem services, as measured by the first phase of the UK NEA (Nature@Work, Green and Pleasant Land). This appears to be due to the fact that, compared with the baseline, the area of arable crops declines most sharply under these scenarios, due partly to changes in land use but also because of conversion of arable land to other habitats important for ecosystem services (e.g. woodland). Taken together these results imply a trade-off between overall value for ecosystem services and conservation of farmland birds, and highlight the need to consider the specific impacts of land use change on biodiversity, alongside other ecosystem services. Marine ecosystem services Only a limited attempt was made to model marine ecosystem services during the first phase of the UK NEA. In the follow-on we have conducted preliminary work to produce spatially explicit models for three important marine ecosystem services: fisheries landings, aquaculture production and carbon sequestration. We made comparisons between baseline data and time slices for 2015, 2030 UK NEAFO Work Package 7: Operationalising scenarios 9 and 2060 under four of the UK NEA scenarios that were considered most relevant for the sector, and mapped these across UK territorial waters. There is a high degree of uncertainty associated with the models, mainly due to a lack of suitable data and poor knowledge of the drivers of change. In many cases, in the absence of robust quantitative models, we needed to take the qualitative descriptions of the UK NEA scenarios and combine these with expert knowledge to estimate changes in the three types of ecosystem service. We estimated that in three of the four scenarios: Nature@Work, Local Stewardship and National Security, fisheries landings would be, by 2060 only slightly lower or at higher levels than they are today. Under World Markets, however, projected landings would decline significantly by 2060, due to a lack of regulation combined with high levels of investment from private capital. In the light of this, it was interesting that aquaculture was at higher levels under World Markets than under any of the other scenarios, although all of them showed higher levels than the baseline. This was because under this scenario more investment capital would be available to invest in fish farms. We believe that carbon sequestration would be most likely to be impacted by the World Markets and Natural Security, due to higher CO2 emissions causing an increase in ocean acidification. Our results, although tentative, mark a significant first step in attempts to map and project the impact of possible future change on marine ecosystem services. Cultural Ecosystem Services In the first phase of the UK NEA, the relationship between the drivers of change and cultural ecosystem services (CES) was mainly explored through the impact they had on land cover. For UK NEAFO, we additionally used the Monitor of Engagement for the Natural Environment (MENE) dataset. We examined how the UK NEA scenarios can be used as a framework to explore the relationship between the supply of cultural spaces in the landscape and peoples preferences for different types of natural spaces and practices in them. We have developed a Bayesian Belief Network (BBN) that allows users to explore these relationships interactively and look at the potential impacts of changes socio-demographic structure of the kind described by the UK NEA scenarios. Our spatial analysis of the MENE data showed that people tend to select locations with higher woodland cover than the average for the surroundings, when they travel intermediate distances from their home, but that this tendency declines when they travel longer distances. Woodland cover is projected to double under both Nature@Work and Green and Pleasant Land, and both provide more opportunities to visit woodland close to home than under scenarios such as World Markets. However, our analysis shows that on the basis of the current geography of people and woodlands, the way planting is targeting under Green and Pleasant Land has the potential to deliver greater joint benefits from biodiversity change and cultural ecosystem services than Nature@Work. The BBN we have developed using the HUGIN Expert software allows the relationships within the MENE data to be explored interactively; it is hosted on a prototype website that is open to the wider community. By examining the relationships between socio-demographic characteristics of the MENE respondents, the types of natural spaces they visit and the activities they do in them, this BBN tool allows users to explore the impacts of possible future change on the supply and demand of CES. Conclusion How can plausible future scenarios help understand, manage and communicate the consequences of changes in ecosystem services across all scales? In this work we have shown that they can be used to promote understanding by the deliberative processes that they engender. The UK NEA scenarios appear to be sufficiently rich and comprehensive to support debate across a wide range of topic areas relevant to current policy concerns. The scenarios can also help understanding by providing a framework in which current models can be applied and the outcome used both to test the plausibility of the scenarios themselves and to deepen the insights that can be derived from them. These analytical ‘scenario products’ can be equally important both in terms of deepening our understanding of the assumptions on which the scenarios are built and in stimulating debate about their implications. We have shown that the distinction between the ‘process’ and ‘product’ dimensions of scenario thinking is a useful one, given the many ways scenarios can be used. The distinction clarifies some of the different purposes and problems that scenarios work seeks to address. However, our work also demonstrates that both components have their strengths, and neither can be taken isolation. If we are to use scenarios to understand, manage and communicate the consequences of changes in ecosystem services across different scales and in different contexts, then targeted analytical studies developed within the qualitative framework of the UK NEA scenarios, can enrich our understanding of today’s issues and how we might respond to them

Relative Roles of Grey Squirrels, Supplementary Feeding, and Habitat in Shaping Urban Bird Assemblages

Non-native species are frequently considered to influence urban assemblages. The grey squirrel Sciurus carolinensis is one such species that is widespread in the UK and is starting to spread across Europe; it predates birds’ nests and can compete with birds for supplementary food. Using distance sampling across the urbanisation intensity gradient in Sheffield (UK) we test whether urban grey squirrels influence avian species richness and density through nest predation and competition for supplementary food sources. We also assess how urban bird assemblages respond to supplementary feeding. We find that grey squirrels slightly reduced the abundance of breeding bird species most sensitive to squirrel nest predation by reducing the beneficial impact of woodland cover. There was no evidence that grey squirrel presence altered relationships between supplementary feeding and avian assemblage structure. This may be because, somewhat surprisingly, supplementary feeding was not associated with the richness or density of wintering bird assemblages. These associations were positive during the summer, supporting advocacy to feed birds during the breeding season and not just winter, but explanatory capacity was limited. The amount of green space and its quality, assessed as canopy cover, had a stronger influence on avian species richness and population size than the presence of grey squirrels and supplementary feeding stations. Urban bird populations are thus more likely to benefit from investment in improving the availability of high quality habitats than controlling squirrel populations or increased investment in supplementary feeding

Capturing residents' values for urban green space: mapping, analysis and guidance for practice

Planning for green space is guided by standards and guidelines but there is currently little understanding of the variety of values people assign to green spaces or their determinants. Land use planners need to know what values are associated with different landscape characteristics and how value elicitation techniques can inform decisions. We designed a Public Participation GIS (PPGIS) study and surveyed residents of four urbanising suburbs in the Lower Hunter region of NSW, Australia. Participants assigned dots on maps to indicate places they associated with a typology of values (specific attributes or functions considered important) and negative qualities related to green spaces. The marker points were digitised and aggregated according to discrete park polygons for statistical analysis. People assigned a variety of values to green spaces (such as aesthetic value or social interaction value), which were related to landscape characteristics. Some variables (e.g. distance to water) were statistically associated with multiple open space values. Distance from place of residence however did not strongly influence value assignment after landscape configuration was accounted for. Value compatibility analysis revealed that some values co-occurred in park polygons more than others (e.g. nature value and health/therapeutic value). Results highlight the potential for PPGIS techniques to inform green space planning through the spatial representation of complex human-nature relationships. However, a number of potential pitfalls and challenges should be addressed. These include the non-random spatial arrangement of landscape features that can skew interpretation of results and the need to communicate clearly about theory that explains observed patterns

Spatio-temporal variation in predation by urban domestic cats (Felis catus) and the acceptability of possible management actions in the UK

Urban domestic cat (Felis catus) populations can attain exceedingly high densities and are not limited by natural prey availability. This has generated concerns that they may negatively affect prey populations, leading to calls for management. We enlisted cat-owners to record prey returned home to estimate patterns of predation by free-roaming pets in different localities within the town of Reading, UK and questionnaire surveys were used to quantify attitudes to different possible management strategies. Prey return rates were highly variable: only 20% of cats returned ≥4 dead prey annually. Consequently, approximately 65% of owners received no prey in a given season, but this declined to 22% after eight seasons. The estimated mean predation rate was 18.3 prey cat−1 year−1 but this varied markedly both spatially and temporally: per capita predation rates declined with increasing cat density. Comparisons with estimates of the density of six common bird prey species indicated that cats killed numbers equivalent to adult density on c. 39% of occasions. Population modeling studies suggest that such predation rates could significantly reduce the size of local bird populations for common urban species. Conversely, most urban residents did not consider cat predation to be a significant problem. Collar-mounted anti-predation devices were the only management action acceptable to the majority of urban residents (65%), but were less acceptable to cat-owners because of perceived risks to their pets; only 24% of cats were fitted with such devices. Overall, cat predation did appear to be of sufficient magnitude to affect some prey populations, although further investigation of some key aspects of cat predation is warranted. Management of the predation behavior of urban cat populations in the UK is likely to be challenging and achieving this would require considerable engagement with cat owners

Linking ecosystem services, urban form and green space configuration using multivariate landscape metric analysis

Context: Landscape metrics represent powerful tools for quantifying landscape structure, but uncertainties persist around their interpretation. Urban settings add unique considerations, containing habitat structures driven by the surrounding built-up environment. Understanding urban ecosystems, however, should focus on the habitats rather than the matrix. Objectives: We coupled a multivariate approach with landscape metric analysis to overcome existing shortcomings in interpretation. We then explored relationships between landscape characteristics and modelled ecosystem service provision. Methods: We used principal component analysis and cluster analysis to isolate the most effective measures of landscape variability and then grouped habitat patches according to their attributes, independent of the surrounding urban form. We compared results to the modelled provision of three ecosystem services. Seven classes resulting from cluster analysis were separated primarily on patch area, and secondarily by measures of shape complexity and inter-patch distance. Results: When compared to modelled ecosystem services, larger patches up to 10 ha in size consistently stored more carbon per area and supported more pollinators, while exhibiting a greater risk of soil erosion. Smaller, isolated patches showed the opposite, and patches larger than 10 ha exhibited no additional areal benefit. Conclusions: Multivariate landscape metric analysis offers greater confidence and consistency than analysing landscape metrics individually. Independent classification avoids the influence of the urban matrix surrounding habitats of interest, and allows patches to be grouped according to their own attributes. Such a grouping is useful as it may correlate more strongly with the characteristics of landscape structure that directly affect ecosystem function

Changes in the distribution of red foxes (Vulpes vulpes) in urban areas in Great Britain: findings and limitations of a media-driven nationwide survey

Urbanization is one of the major forms of habitat alteration occurring at the present time. Although this is typically deleterious to biodiversity, some species flourish within these human-modified landscapes, potentially leading to negative and/or positive interactions between people and wildlife. Hence, up-to-date assessment of urban wildlife populations is important for developing appropriate management strategies. Surveying urban wildlife is limited by land partition and private ownership, rendering many common survey techniques difficult. Garnering public involvement is one solution, but this method is constrained by the inherent biases of non-standardised survey effort associated with voluntary participation. We used a television-led media approach to solicit national participation in an online sightings survey to investigate changes in the distribution of urban foxes in Great Britain and to explore relationships between urban features and fox occurrence and sightings density. Our results show that media-based approaches can generate a large national database on the current distribution of a recognisable species. Fox distribution in England and Wales has changed markedly within the last 25 years, with sightings submitted from 91% of urban areas previously predicted to support few or no foxes. Data were highly skewed with 90% of urban areas having <30 fox sightings per 1000 people km-2. The extent of total urban area was the only variable with a significant impact on both fox occurrence and sightings density in urban areas; longitude and percentage of public green urban space were respectively, significantly positively and negatively associated with sightings density only. Latitude, and distance to nearest neighbouring conurbation had no impact on either occurrence or sightings density. Given the limitations associated with this method, further investigations are needed to determine the association between sightings density and actual fox density, and variability of fox density within and between urban areas in Britain

Designing indicators for assessing the effects of marine protected areas on coral reef ecosystems : a multidisciplinary standpoint

The present paper aims at identifying and assessing indicators of the effects of Marine Protected Areas (MPAs) in coral reef regions, based on a bibliography review in ecology, economics and social sciences. First the various effects Studied within each of these domains and the variables used to measure them were censused. Potential ecological indicators were assessed through their link with the question used (here termed "relevance") and their "effectiveness" which encompasses the issues of precision, accuracy and statistical power. Relevance and effectiveness were respectively measured by the frequency of use of each indicator and the proportion of significant results in the reviewed articles. For social and economic effects, the approach was not possible due to the low number of references: we thus discussed the issue of finding appropriate indicators for those fields. Results indicate: 1- the unbalance in literature between disciplines: 2- the need for protocols and methodologies which include controls in order to assess MPA effects: 3- an important proportion of ecological indicators with low effectiveness: 4- the large number of ecological effects still not studied or not demonstrated at present