Biogeography and Ecology

The effects of sea level rise on the ecology of coastal wetlands, Estonia

This project (2008-11) aims to establish the possible impacts of predicted sea level rise due to climate change upon the plant and soil invertebrate communities of coastal wetlands in West Estonia, which are of international nature conservation value. It uses dGPS to map the micro-topographic relief of the coastal wetlands, hydrological monitoring to establish the hydroperiod, and field sampling to determine soil invertebrates and plant species. The data will be integrated within a GIS to map the effects of sea level rise under predicted climate change scenarios in order to develop more sustainable management for Baltic coastal wetlands. The project is a collaboration with Tartu University of Life Sciences. (Chris Joyce, Niall Burnside)

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Relationship between micro-topography and vegetation in Estonian coastal wetlands: implications for climate change

This study examines the relationship between micro topography and vegetation and invertebrate community structure in coastal wet grasslands. The project seeks to establish the relationships which exist between micro topography and vegetation and invertebrate species communities using field survey and geomatic techniques. LIDAR data is then included to assess its potential to create predictive models of species distribution. Finally, future coastal wetland extent will be estimated taking into account present and future predicted marsh accretion rates, isostatic uplift and IPCC sea level rise estimations. This tool will be useful in developing future conservation management strategies for coastal wetlands. (Ray Ward, Niall Burnside, Chris Joyce, Kalev Sepp)

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Relationships between sediment characteristics and invertebrate communities in coastal wetlands

This project (2008-10) aims to elucidate relationships between sediment character and invertebrate community composition in order to assess the ecological status, and develop management and restoration, for intertidal wetlands. Field surveys at nine sites in southern England incorporated sediment cores and benthic samples, with sediment physical and geochemical properties analysed and all species identified, in order to provide a multivariate discrimination of community patterns. The project is funded by Natural England as part of their SSSI condition assessment programme. (Chris Joyce)

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Species-area and SLOSS relationships in chalk grassland fragments

The project seeks to examine the occurrence and distribution of plant species among refuge fragments of chalk grassland, and to determine whether these patterns of distribution relate to species richness and patch biogeography. At present our investigations show that the combined effects of patch area, habitat diversity and to a lesser extent connectivity and patch complexity are important in determining species richness in chalk grassland fragments. (Niall Burnside, Steve Waite)

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Assembly rules and chalk heath plant communities. A biogeographical approach

In the South and South-East of Britain, chalk grassland makes up part of a mosaic of different habitats that include calcareous (chalk) heath. True calcareous heath communities contain an intimate mixture of calcicole and calcifuge species growing in shallow loam over chalk. The aim of this project is to establish the species selection processes and assembly rules that govern or explain which plant species are able to establish on chalk heaths, i.e., to identify (sensu, Keddy, 1992) the particular environmental species filters that operate at different spatial and temporal scales. The study area, Lullington Heath National Nature Reserve in Sussex, has 25ha of chalk heath and is regarded as the largest and best example of this habitat in Britain. (Amanda Flint, Anja Rott, Steve Waite and Niall Burnside)

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Bioturbation by ants in chalk grassland systems: Above and below surface interactions and the role of management

The aim of this project is to discuss the role that ants play as ecosystem engineers within calcareous grassland habitats in the South Downs. The project looks at the interactions between above and below surface processes including micro-topography, mychorrizal relationships, soil and vegetation interactions with a focus on how influential ecosystem engineering is at the landscape scale. The project also considers the role of different management regimes within protected habitats and how these influence ant populations and the subsequent effect on ecosystem functioning. (Mike Dilley, Niall Burnside, Chris Joyce, Roger Smith)

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The role of Vesicular Mycorrhizal Fungi in calcareous grassland communities on the South Downs

The research programme has characterised species presence and abundance in chalk grassland communities and examined the role of Vesicular Mycorrhizal Fungi. Using field and laboratory trials, the project has identified the changes that occur after the disruption of the symbiotic relationship by the application of the fungicide Iprodione at regular intervals. Early results of the laboratory turf trial show Brachypodium pinnatum to be highly mycorrhizal and competition between Brachypodium pinnatum and Bromus erectus to be mediated by mycorrhizal fungi. The application of fungicide at fairly high doses and the reduction in mycorrhizal activity appears to lead to size inequality in the remaining species, i.e. they increase in size. This suggests that mycorrhizal fungi may have a role in maintaining size equality in chalk grassland communities. (Roy Holm, Niall Burnside, Chris Joyce, Steve Waite)

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The determination of Ghyll Woodland types in the Weald

The aim of this project is to collate ground survey material on the Ghyll Woodlands of the Sussex Weald and to apply GIS and multivariate statistical techniques to examine the flora, geomorphology and management of these biologically important systems. The occurrence and distribution of species within habitat islands such as these is of key concern to conservationists. There is a need to understand the patterns of species occurrence and richness among habitat patches within a fragmented landscape. (Andy Flint, Niall Burnside, Steve Waite)

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The impacts of landscape fragmentation, connectivity and habitat quality on hazel dormouse population viability

This project draws together inter-disciplinary expertise in mammal ecology, landscape ecology and genetics, to investigate an aspect of conservation biology of a protected UK species which has previously become extinct in half is former range, the hazel dormouse (Mucardinus avellanarius). We aim to investigate the effects of landscape quality, structure, isolation and fragmentation on hazel dormouse population viability by integrating methods in determining species occupancy, habitat quality assessment, GIS landscape ecology analysis and current developments in genetic markers for this species. (Dawn Scott, Niall Burnside and Andy Overall)

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Post release dispersal and establishment rates of water voles to determine the impact of landscape structure and habitat on re-establishment

Water vole populations had declined across the UK by 90% in the last 20 years and are now a UK BAP priority species. This is one of the most rapid and dramatic declines of any British mammal. Populations in Sussex are also critically low with many so small and fragmented they are vulnerable to extinction. Only two large natural populations remain with a further population recently re-established by release. The aim of this study was to investigate land use, habitat quality and landscape structure to enable water vole population connectivity within Sussex. We undertook landscape, connectivity and habitat assessment between two currently isolated populations, one naturalistic and one re-established, to determine rates of dispersal, persistence and establishment of a released population. The aim was to identify which factors are potentially limiting dispersal, establishment and connectivity between these populations. This information can be used to develop a landscape management plan to aid the establishment of a viable meta-population network to link populations securing the long term persistence and growth of water voles in Sussex. (Dawn Scott, Fran Southgate, Rowenna Baker and Peter King, SWT and WWT)

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Impacts of re-introductions on water vole genetics

Water vole populations in the UK have suffered an estimated 90% decline. The main drivers in this decline are habitat loss, fragmentation and predation. One of the Species Action Plan targets is to restore water voles to their former distribution. To help achieve this, restoration approaches involving reintroduction of captive bred individuals have become common activity to re-establish or boost water vole populations. However, the consequence of reintroductions on the long term population viability has received little attention. The main question is: 'what is the population viability of re-established or 'boosted' populations compared to wild populations and ultimately what are the potential consequences of this on the long term population persistence? One way of investigating population viability is to look at genetic variability within and between populations. One of the limitations in genetic studies is the cost and difficulty of obtaining sufficient samples. Many genetic studies have involved direct sampling from captured individuals. Recent successes in non-invasive sampling using hair tubes have shown potential for obtaining genetic samples remotely. This project aims to adapt and implement a remote non-invasive sampling method to obtain samples for an investigation of genetic viability of water vole populations in Sussex. (Dawn Scott and Andy Overall)

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Comparative ecology of brown hyaena (Hyaena brunnea) inside and outside National Parks in South Africa

It is estimated that there are fewer than 1,700 free ranging brown hyaena in South Africa as a whole with its regional status varying from threatened to near threatened. Many populations of brown hyaena exist in unprotected areas, however within these areas brown hyaenas have been shot, poisoned, trapped and hunted with dogs in predator control programmes. Such activities can drastically reduce brown hyaena numbers, and it is essential for conservation of this species to know how many brown hyaenas exist outside protected areas. Many protected areas and their wildlife populations are limited by their size and location. They can only hold so many individuals; a limit determined by how much food and resources are available. Small reserves may not have enough resources to maintain viable, long lasting populations of wide ranging animals such as the brown hyaena and vultures. In addition, the animals they do house may be forced into competition with other species they may not normally encounter under natural conditions; hence their ecology and behavior may also be unnatural. Animals inside protected areas are frequently isolated from other potential populations by being surrounded by inaccessible or inhospitable human dominated landscapes. Small isolated populations can face problems such as inbreeding, which can threaten the long-term survival of species. Hence we must look at unprotected, commercial landscapes to ensure the long term survival of many of these species. This requires addressing human-wildlife conflict issues and increasing the understanding and value of maintain such species in commercial landscapes. Commercial landscapes have a potential role in future biodiversity conservation, but to develop this role, resolutions to ongoing human-wildlife conflict need to be found along with biodiversity conservation awareness and sound conservation management practices. One of this project's overall aims is to assess the biodiversity and conservation value of commercial areas outside protected areas. If carnivores can survive well outside protected areas, it is likely that many other endangered animals could, as well. (Dawn Scott and Richard Yarnell)

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Molecular ecology of brown hyaenas

The project aims to compare the genetic variability of three neighbouring, but isolated, brown hyaena populations. Two populations are protected and enclosed by impenetrable fences inside two National parks, and the third is free ranging in the hinterland. Our aim is to obtain tissue from the three populations in order to estimate the magnitude of close inbreeding and the degree of genetic differentiation amongst the populations. The results will provide the first insights into brown hyaena genetic population structure which will have consequences for the future conservation of this species. (Andy Overall and Dawn Scott and Richard Yarnell NTU)

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Spatial ecology and occupancy of stoats and weasels

For many species, knowledge of distribution, abundance and occupancy is incomplete or absent. Numerous methods have been developed to study carnivores but each has inherent advantages and disadvantages that vary depending upon focal species ecology as well as project aims and constraints. Few mammals in Britain that are as widespread and well known as weasels and stoats are as poorly understood. Presently the best way of monitoring populations is to capitalise on data collected by gamekeepers. The Game Conservancy Trust (GWT) collates trapping and shooting records as part of their National Game Bag Census (NGBC), and can be used to describe national trends in Weasel and Stoat numbers and distribution however there has been recent recognition for the need for increased detections and new techniques on these species. Presently there is no quantified method or technique to effectively assess and monitor occupancy for Stoats and Weasels within the UK.

The aims of this study are therefore:

1. Assessment of three methods that have been successfully used in previous carnivore assessment studies with the objective of identifying most effective method for weasels and stoats.
2. Application of most effective method to provide species estimates of distribution, abundance and occupancy.
3. Expansion of effective method and monitoring strategy to a county scale monitoring programme.

(David Oakley and Dawn Scott)

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The impacts of persecution on the population ecology of the Black Backed Jackal (Canis mesomelas) in South African farmland ecosystems

The silver or black backed jackal is omnivorous meso-carnivore (Estes 1991), that is currently subjected to mass persecution across South Africa. Recent studies have shown that over 17,000 are killed annually in the North West Province alone (Thorn, 2009). The consequence of high levels of anthropogenic mortality on carnivore population ecology has received little research in South Africa. This information is vital to determine the potential long term population consequences of high persecution and would inform effective and economically viable population control methods. Persecution is driven by the economic losses resulting from depredation of livestock by jackals. This has lead to persistent unregulated and opportunistic lethal control measures in an attempt to reduce population densities. However, continued reports of jackal numbers in farmlands (Thorn 2009) suggest that current population control strategies are not effective. Therefore, ecological and demographic factors must vary to sustain population numbers. For example, due to the highly territorial and monogamous nature of this species (Estes 1991), removal of territory holding (alpha) individuals has the potential to dramatically influence the density, structure and stability of a resident farmland population. To surmise, this study will address the effects of culling on population densities of jackals by examining population structure, fecundity, territory size and territory stability across gradients of persecution. This will provide a greater understanding of the ecological consequences and effectiveness of unregulated predator control in order to more accurately inform the management process of this species. (Robert James and Dawn Scott)

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Population ecology and conservation genetics of the smooth snake (Coronella austriaca) in a fragmented lowland heath landscape

Substantial losses and fragmentation of southern England's lowland heathland has occurred in recent times. This forms the primary habitat of the smooth snake (Coronella austriaca), Britain's rarest snake and yet research examining the population ecology and conservation genetics of this species in the UK remains limited. Based on three years study using a combination of field studies, laboratory experiments, mathematical modelling and genetic analyses the following was examined:

• What factors determine smooth snake presence on heath patches following fragmentation
• How does variation in the habitat of these remnant patches affect smooth snake abundance
• What factors determine the genetic structure of smooth snake populations at multiple spatial scales
• How female investment in reproduction varies and determining clutch paternity using genetic techniques
• The role chemoreception plays in prey and kin discrimination for newborn smooth snakes

(Angelo P. Pernetta)

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Conservation based autecological studies of endemic Mascarene Island

The reptile fauna of Mauritius has suffered dramatic declines and species extinctions as a result of significant overexploitation, habitat loss and the introduction of non-native species. This project conducted a detailed ecological study of Telfair's skink (Leiolopisma telfairii) on Round Island, located 22.5 km off the north coast of Mauritius. The results of this research were used as the basis for an ongoing translocation programme to re-introduce these lizards to neighbouring islands that formed part of their historic range. More recently the project has been involved in research examining the autecology of the orange-tail skink (Gongylomorphus sp.) endemic to Flat Island, Mauritius. In the future it is hoped to expand this area of research to incorporate studies of endemic reptiles and amphibians on other Indian ocean island ecosystems. (Angelo P. Pernetta)

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Monitoring and mitigating the impact of the global trade in live reptiles and amphibians

The popularity of reptiles and amphibians as "exotic pets" has increased dramatically in recent years. However, research examining the impact and sustainability of this trade remains limited. This project undertook a review of the dynamics of the global trade in monitor lizards (Varanus spp.) based on CITES trade figure. In the future it is intend to continue this research by examining how consumer attitudes could affect the establishment of a sustainable trade in live reptile and amphibian species. (Angelo P. Pernetta)

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Pollination Ecology: pollen quality and bumble bee conservation

Bumblebees play a pivotal role in ecosystems - they are not only major pollinators of the majority of our wildflowers, but they are also of enormous commercial importance due to the eco-services they provide by pollinating many arable and horticultural crops. Considering that the UK only has 6 relatively common species with other species facing national extinction, conservation and restoration of bumblebee species is vital. One main constraint current bumblebee populations face is the availability of a mosaic of habitats to provide for their nesting and feeding needs. Above all the presence of a variety of suitable flowers present throughout the season is crucial to ensure that the right quality of food (i.e. pollen and nectar) can be collected. The current limited floral choice in agricultural landscapes alongside the variable rewards all flowers/plants offer has led to certain pollen and nectar rich habitats becoming a particular benefit to bumblebees. These conservation initiatives are of high importance to the health of a hive as the reproductive success of a colony is reliant upon a consistent nutritious source of pollen. Yet the efficacy of floral species within seed mixture schemes in relation to the flower acceptance and foraging effectiveness of bumblebees is not fully understood. This study assessed and evaluated the complex biotic interactions of bumblebee communities on commercial seed mixtures. Our results will present an assessment of the proportion of pollen collection visits made by bumblebees in relation to pollen quality. (Anja Rott and Rob Fowler)

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Orchid Conservation: Burnt Orchids and Pollination

The burnt orchid, Neotinea ustulata L., is one of the rare orchid species found only in a few areas of the South Down, preferentially on South facing slopes on old moderately rabbit-or sheep-grazed pastures. We find two varieties of the Burnt Orchid on the South Downs - an early flowering variety (flowering in spring in May) and a late flowering variety (flowering around the July / August). Interestingly populations of both varieties occur on different sites and in the past used to be a common sight on the chalk and limestone hills of Southern England. Unfortunately, the Burnt Orchid has suffered one of the most severe declines in the last 50 years, largely due to changes in agricultural practices. The project funded by the South Downs Society studied the insect visitors to this rare orchid to obtain an insight into one of the driving factors influencing seed set. We found that the insect visitors are generalist, meaning they visit different species of flowers. These results are particularly important information as they show that the insects visiting the Burnt Orchid are not highly specialised pollinators and that a good diversity of flowering plants present at the stand should therefore provide enough insects visiting the flowers to ensure pollinations. (Anja Rott and partly funded by research grant from South Downs Society).

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Oak Herbivory: BSO Trials in Kent

This ongoing study investigates the silvicultural form of young oak (Quercus robur and Quercus petraea) trees growing in breeding seedling orchards (BIHT Oak group - Northmoor Trust). The trees in the plantation were grown from acorns collected from parent trees across the UK, Ireland, France and the Netherlands and are currently surveyed in regard to plant parameters and corresponding herbivory loading (Anja Rott)

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Dung Beetle Ecology in South Africa

Dung beetles (Coleoptera; Scarabaeidae) are generally well recognized focal taxons which are frequently used to describe and monitor spatial and temporal patterns of biodiversity. Furthermore their diversity is closely linked to mammal diversity due to their long history of ecological specialization in feeding and breeding in dung and carrion and hence dung beetle species composition and abundance be used to evaluate response to all kinds of disturbance such as habitat or vegetation changes. Scarabaeine dung beetles primarily use mammal dung as adult and larvae food resource, the latter by laying the eggs within the dung itself, or within the brood balls buried in the soil. Not only does this lifestyle of utilising mammal faeces mean they consume and manipulate dung, but they also relocate it, thus contributing many important ecological functions such as soil aeration, acceleration of nutrient recycling, increase plant yield and secondary seed dispersal expelled in mammal dung. Dung beetles are especially suited for understanding these patterns due to the ease of sampling via baited traps. Therefore quick surveys as well as long term monitoring of dung beetle communities can reliably inform successful conservation and management practices in a cost efficient manner. Thisresearch project has been running since September 2009 investigating the variation in dung beetle community on faeces from mammals with different dietary requirements. This study aims to investigate the tightly linked changes in mammal-dung beetle assemblages with focus on density of herbivorous mammals and the associated dung beetle and vertebrate scavengers' community. (Anja Rott, Dawn Scott and Robert James)

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Urban Biodiversity In Brighton

Urban areas are predicted to grow significantly in future with increased human population growth resulting in increased urbanisation. However our understanding of how urbanisation affects wildlife is currently limited in the UK. Urbanisation can be beneficial to some species that can adapt to it, but be detrimental to others that cannot tolerate habitat change. Those that benefit from urban habitats can increase in numbers, compete for resources and cause damage and disturbance that can lead to human-wildlife conflict in urban areas. For humans and wildlife to coexist in urban areas and for towns and cities to support biodiversity we need a better understanding of urban wildlife ecology and how people can support and coexist with biodiversity in urban habitats. This will be the first detailed investigation of wildlife within a city which involves surveying across multiple taxonomic groups (mammals, birds, plants and invertebrates) and includes landscape analysis with GIS and a population genetics element. Our goal is to provide a better scientific understanding of urban wildlife ecology and to engage urban stakeholders in monitoring and enhancing urban biodiversity for the benefit of all.

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