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Beekeeping is used by numerous development agencies in their efforts to promote livelihood activities that reduce poverty and provide incentives for forest conservation. Besides short-term monetary focused project evaluation reports, there is little evidence on the effectiveness of beekeeping to achieve the above goals. In this thesis I set out to examine the contribution of beekeeping to household wellbeing and conservation motivations. I conducted this study in four rural communities in Central Tanzania using a mixed methods approach. First, I identified predictors of beekeeping adoption, dependence, and success. I found that beekeepers were often also livestock keepers and wild honey hunters. The results also indicate that beekeeping uptake was mainly motivated by the prospect of cash income, but the lack of suitable land, means to acquire hives and technical knowledge were significant inhibitors. I also found that beekeeping training provided by governmental organisations did not lead to improved beekeeping success when compared to local training provided by neighbours and family members. Lastly, elite capture of project benefits was a frequent occurrence when project participation was linked to the requirement to form associations. I then assessed whether beekeepers were better-off in ten crucial life domains than their non-beekeeping peers and whether beekeeping was effective in filling an income gap during the agricultural year. I observed that beekeepers were more food secure, more resilient and had more farm-and non-farm assets. I found that beekeeping income contributed to additional cash income during distinct periods of the year, but did not fully bridge shortage periods. Finally, I analysed the associations between beekeeping and conservation by assessing a range of factors contributing to forest-friendly behaviour. I found beekeeping to be linked to more intensive forest use, more positive attitudes towards the forest and a stronger appreciation of conservation benefits. These observed effects were however mitigated by beekeepers' engagement in forest destructive behaviours and their insufficient influence within their communities to protect forest resources. These findings are of importance, as considerable efforts are being paid to the promotion of beekeeping in developing countries, including in the context of REDD+. The methodology chosen for this research as well as the short extent of time spent in study communities preclude however definite conclusions on differences between beekeepers' and non-beekeepers' wellbeing and conservation impact. Given how ubiquitous xi engagement in beekeeping in Tanzania is, it is entirely conceivable that the benefits of beekeeping on wellbeing and conservation motivations are either much larger - yet not captured in the data collected for this study - or that they offer a relative easily accessible supplement to local livelihoods where alternatives are scarce. The results of this study can still point to opportunities for better-targeted investment in beekeeping in the context of linked conservation and development interventions by improving the selection of beneficiaries and the design of project delivery mechanisms, setting in place a range of factors which can improve beekeeping benefits and identifying further measures potentially needed to achieve enhanced livelihood and conservation goals.

The need to achieve human development without harming the natural systems on which all life depends, is one of the greatest challenges of our times. The aim of this research is to deploy and develop social-ecological systems thinking to a miombo forest landscape in north west Zambia where thousands of people make a living from forest beekeeping. There exists significant critique about whether trade in non-timber forest products (NTFPs) can help deliver the dual goals of poverty alleviation and forest maintenance. Trade in forest honey appears to be an exceptional case, yet inadequately studied. This research fills a gap in understanding about the link between forest honey trade and forest maintenance. Honey trade is already commercialised in north west Zambia and so provides a case study scenario within which to ask, Given that the market for honey is assured, do beekeepers maintain forests'? Case study methodology found that trade is driving an increase in forest beekeeping, with income invested in education, in farming and as capital for other enterprises. Self-reported measures of economic wellbeing showed beekeepers to be slightly better off than non-beekeepers. Beekeepers negotiate de facto rights to hive sites and engage in 'early burning' to mitigate potential damage to flowers, bees and trees caused by dry season fires. Beekeepers apply this forest protection tool over thousands of hectares of forest. Beekeepers do not manage forests using scientific principles of inventory and planning, and features of a common-property management regime are largely absent. The study reveals entities and components of a forest beekeeping livelisystem - a complex, knowledge rich system where ecological elements and human elements are intricately connected in a robust social-ecological system The system is driven by trade, is productive and works with minimal external costs. The role beekeepers play in maintaining this forest system must be acknowledged and supported by development planners, local authorities and leaders and consumers who buy the honey.

Although apiculture has been practised for thousands of years, many aspects of the honeybee, including the responses to the ambient environment through their central nervous system and their behaviours at an individual level, especially the flight behaviours, are yet to be understood thoroughly. Due to the dramatic decline in honeybee populations across the world, such studies have shown more significance. The development of instrumentation and software of an automated 3D insect detecting and tracking system is proposed. This inexpensive system comprises two orthogonally mounted video cameras with an observing volume of over 250 m3 and an offline analysis software system that outputs 3D space trajectories and inflight statistics of the target honeybees. The imaging devices record at 2.7K, 60 frames per second and require no human intervention once set up. The software module uses several forms of modern image processing techniques with GPU-enabled acceleration; it is able to minimise the effect of highly cluttered stationary background objects and moving artefacts whose characteristics are distinguishable from those of bees. The statistics of bees' flight activity are presented and discussed. This system provides a streamlined and low-cost approach to the study of inflight behaviours of bees and other insects. It will find applications in the optimisation of pollination strategy, population dynamics and hive health, accurate knowledge of which is predicated upon a better understanding of the inflight behaviours of bees at the individual level.

The global food system is essential for sustaining human life, yet in its current form it does so at a great cost to both human and environmental health. Food insecurity and diet-related disease are responsible for 70% of deaths worldwide, and the global extinction rate is ~1000 times estimated background rates due to the widespread destruction of wild habitat for agriculture. The production of livestock for animal protein is a key driver of both trends. This thesis considers the potential of edible insects in existing agricultural systems to mitigate these problems, with a focus on the role of chitoumou (Cirina butyrospermi), the commonly consumed shea caterpillar harvested from agroforestry systems in Burkina Faso, West Africa. I begin this thesis with a review of the role of edible insects in agricultural systems worldwide. Though certain insects are currently touted for commercial scale production, many popular edible insects are already harvested from existing systems, in which they prey on plant crops. These insects often cause damage to crop yields, but also provide vital provisioning, regulating, maintaining and cultural ecosystem services. Yet, few data are available to enable farmers and policymakers to weigh up the costs and benefits of edible insects in agricultural systems. Therefore, I examine the contributions of chitoumou – a popular edible insect in a region with acute food insecurity and environmental degradation – to food security, crop yields and biodiversity. Firstly, I evaluate the contribution of shea caterpillars to food security. I show that animal protein consumption and food security are higher during caterpillar season, and that higher food security is associated with caterpillar collection, sale and consumption. Shea caterpillars contribute positively to food security, but this effect is seasonal. Secondly, I investigate the relationship between defoliation by shea caterpillars and crop yields. Observational data show that defoliation does not have a negative association with yields of either shea (Vitellaria paradoxa) or maize (Zea mays). This challenges assumptions held by some stakeholders that it is necessary to take measures to eradicate these insects. Thirdly, I look at the relationship of caterpillars to biodiversity, using defoliation as a proxy for caterpillar abundance and bird abundance as a proxy for biodiversity. I find no significant relationship, suggesting that defoliation by caterpillars is not a significant threat to biodiversity in this region. Consequently, policymakers and smallholder farmers alike should recognize that shea caterpillars are not pests, and that the retention of shea trees will promote food security. However, policymakers in particular should be aware that the contribution of shea caterpillars to food security is seasonally limited. For this reason, assessments of food insecurity and strategies to mitigate food insecurity in this region are best conducted out of caterpillar season. Future research that aims to tackle acute global problems of human and environmental health using edible insects should consider the role of insects in existing agricultural systems, and quantify how such insects affect regions where these problems are most severe.

In recent years, dramatic levels of pollinator decline have captured the attention of scientists, policymakers and wider publics. This precipitous drop in honey bees and other pollinators threatens food security and biodiversity. Recent policy initiatives call upon multiple, diverse stake holders to work together for pollinator wellbeing, and wider ecosystem health. Many of these initiatives forefront beekeepers, whose role in both monitoring and ensuring bee health is recognised as paramount. This thesis investigates beekeepers’ knowledge of both honey bees, and the wider environment. Using archival analysis, interviews and participant observation, I demonstrate that long-term beekeepers generate and use Traditional Environmental Knowledge (TEK) through their beekeeping practice. Their knowledge incorporates wide understanding of both the environmental factors that have affected pollinator health since the mid-20th century, as well as the socioeconomic and political drivers behind the physical deterioration of much of the environment that we, and pollinators, rely upon. This research project explores beekeepers’ knowledge within the context of debates on TEK, and Citizen Science. I explore the relationship between formal scientific research and other methods of environmental inquiry and engagement. While there has been a dramatic increase in media, public and scientific attention to pollinator and bee decline, this thesis documents a worrying dissonance between the knowledge and recommendations of long-term beekeepers, and the wider public’s understanding and actions, in response to this environmental challenge. Although beekeepers’ tacit understanding is often deeply infused with wider scientific knowledge, resulting in a uniquely hybrid knowledge, this research finds a hegemonic prioritisation of objectivist epistemologies, which results in a failure for the scientific and policy communities to fully engage with the observations and concerns of beekeepers. While TEK is recognised as supporting environmentally sustainable practices, this epistemological tension limits the capacity for the knowledge of TEK holders, and beekeepers, to be fully utilised.

Infectious diseases shape almost every aspect of nature and society; understanding the multitude of factors influencing infectious diseases is a critical goal of modern evolutionary ecology. This thesis explores this broad topic using theoretical and empirical approaches to understand the forces at work in infectious disease ecology and evolution, with application to the specific system of managed honeybees (Apis mellifera L.). I demonstrate that a well-documented evolutionary trade-off governing pathogen resistance is both constitutive and genetic - critical for supporting assumptions made by mathematical theory. I go further to demonstrate that this trade-off breaks down when the action of selection is reversed, in that when the 'cost of resistance' phenotype is selective for, we do not incidentally select for higher resistance too. This is important for understanding genetic linkage of traits and downstream evolutionary modelling. I undertake theoretical modelling on the topic of spatial structure and how it affects pathogen evolution. In doing so I interrogate a critical assumption made in much of the prior theoretical body, showing that the effect of spatial structure on virulence is quantitatively changed when a core assumption concerning reproduction is relaxed, but is otherwise qualitatively robust. I continue on the theme of spatial structuring and pathogens by developing novel theoretical models on how changing apicultural management alters honeybee population spatial structure, surprisingly leading to only marginal changes in pathogen burden. I stay on this topic to examine empirical data on honeybee colony viriomes in an observation experiment showing that colonies from very intensively managed, migratory backgrounds show elevated viral titres - critical for management and wild bee conservation. I synthesise that the honeybee system is our most informative natural experiment in showing that vectored pathogens are more virulent than directly transmitted counterparts. I also show that outbreaking human epidemics (Zika virus) can threaten apiculture - and by extension livelihoods and agriculture.

Wild bumblebee populations are under increasing threat from both a reduction in natural floral resources, as a direct result of anthropogenic disturbance, and an increase in disease prevalence, including emergent infectious diseases. This is of global concern as bumblebees are not only valued for their economic importance as pollinators but also culturally, as a charismatic component of the natural world. This thesis explores the impacts of phytochemicals found in the pollen and nectar of plants included in Agri-environment scheme (AES) planting strategies on bumblebee health, with a focus on their interactions with prevalent parasites. The five research chapters investigate the impact of a range of phytochemicals on two key bumblebee parasites, using a range of approaches including in vitro cellular growth experiments, in vivo experiments in individual bumblebees, both as larvae and adults, and finally epidemiological experiments on whole bumblebee colonies. In chapter one I review the pertinent literature relating to bumblebee declines and the impact of phytochemicals on pollinator health. In chapter two, larval inoculation with Crithidia bombi (Trypanasomatidae) resulted in no infected larvae seven days following inoculation. This result was critical for the design of subsequent chapters that tested the impact of phytochemicals on larval stages. In addition larvae were identified as disease transmission hubs (chapter published as Folly et al. 2017 Journal of Invertebr Pathol). Chapter three describes the identification of 62 unique phytochemicals from the pollen and nectar of AES plants. In addition, chapter three investigated the impact of four of these AES phytochemicals with known biological activity on C. bombi in vitro. Here caffeine had a significant positive effect on the growth of C. bombi at its ecologically relevant concentration before significantly reducing C. bombi growth at higher concentrations. In chapter four I designed a proof of principle investigation to ascertain if phytochemicals could impact Nosema bombi (Microsporidia) infection in B. terrestris using the isoflavone biochanin A. Biochanin A had a significant prophylactic effect in developing larvae and a significant therapeutic effect in infected adult workers. In chapter five, the phytochemicals caffeine and tricoumaroyl spermidine, which were found in nectar and pollen from AES plants (Chapter three), were tested at their ecologically relevant concentrations against N. bombi in larvae, both prophylactically and therapeutically. Caffeine had a significant prophylactic and therapeutic effect on N. bombi infection intensity. These novel results clearly show that phytochemicals can impact on N. bombi infections in bumblebees. In chapter six, caffeine was continuously fed to wild caught and reared B. terrestris colonies that were infected with N. bombi. Caffeine reduced the overall colony infection prevalence of N. bombi. In addition those bumblebees that were infected had significantly lower infection intensities. This chapter represents the first evidence of the impact of phytochemicals on disease epidemiology in bumblebees. Finally in the discussion chapter I outline the wider reaching implications of my research and discuss how my findings may impact the direction of future research in this area. Overall I found that floral rewards may contain a diverse suite of phytochemicals. Given that bumblebees undertake numerous foraging trips it is likely that a developing colony is consistently exposed to such phytochemicals. Importantly some of these may have positive impacts on bumblebee health by mitigating the impact of diseases. These findings have important implications for both conservation practices and government policy makers.

Critical to supporting populations of wild and managed species in agricultural systems are an improved understanding of mechanisms by which bees enhance crop quality and yield; the factors influencing pollen selection by foraging bees (including pollen diversity and amino acid concentrations); the influence of pollen profiles in determining individual and colony performance; and the response of individuals to insecticides in nectar. Laboratory and field studies addressed these questions using Osmia bicornis and Bombus terrestris audax. In a mixed lowland farm system, O. bicornis reproduction and plant utilisation was investigated in florally-enriched vegetation. A high selectivity for pollen was observed and in the laboratory larval survival was related to the pollen profile of the diet. The role of pollen diversity and amino acid concentrations were investigated in both foraging behaviour and survival, but requires clarification, although poor survival in the laboratory was associated with low amino acid concentrations in a single-species diet of Pinuspollen. In B. terrestris audax, laboratory colony performance was greatest in pollen diets with high concentrations of essential amino acids, but again no consistent relationship with the diversity of pollen species was detected. Results suggest that composition of off-crop vegetation, including those offered in agri-environment schemes, could be modified to better support wild and managed bee populations. Managed O. bicornis, in a cherry orchard experiment, were shown to improve fruit quality, demonstrating a potential commercial application of improved understanding of pollinator biology. Management interventions in farm systems, however, need to consider the potential impacts of insecticides. In laboratory experiments, foraging B. terrestris used colour cues when selecting flowers, but chemical cues to detect nectar spiked with neonicotinoids. Observed sub-lethal toxicity was reversible when clean nectar was offered but further work is required to confirm the mechanism (behavioural or physiological) leading to these findings.

Over the past century there have been substantial declines in farmland biodiversity as a result of the intensification of agricultural practice. Concerns over these declines have led to the development of agri-environment schemes designed to mitigate the effects of intensive agriculture and to benefit biodiversity. Prior to commencing this thesis it was not clear if flower-rich, pollinator-focused agri-environment schemes had a population level impact on wild bees on farmland. Whilst previous work has shown that the creation of flower-rich habitat can provide suitable foraging resources for bumblebees, little was known about the impact of this management on bumblebee population sizes and even less on whether these resources were used by and benefited solitary bees. This thesis compares bee populations between farms with and without flower-rich, pollinator focused agri-environment schemes in Hampshire and West Sussex, UK. Using genetic techniques to estimate colony density, and hence population size, farms implementing targeted schemes had a significantly higher density of bumblebee nests for the four species studied (212 nests/km2 against 112 nests/km2). However, there was no difference in the species richness of bees between these different farm types. When assessing pollen use by solitary bees, flowering plants sown as part of pollinator-focused agri-environment schemes were not widely used, representing 27% of pollen foraging observations and 23% of pollen collected by volume. Only 35% of solitary bee species were found to use sown plants for pollen to a meaningful extent, with most pollen collected from plants persisting in the wider environment. The creation of flower-rich habitat significantly increased resource availability, but did not increase resource diversity. These results indicate that if diverse bee populations are to be maintained on farmland then agri-environment schemes must be developed that effectively increase the number of flowering plant species present at the farm scale.

The honey bee, Apis mellifera, is important both ecologically and economically. Pests and diseases are arguably the greatest current challenge faced by honey bees and beekeeping. This PhD thesis is focused on honey bee disease control including natural resistance by means of hygienic behaviour. It contains eleven independent experiments, ten on honey bee pests and diseases and their control and resistance, and one on stingless bees. Each is written as a separate chapter, Chapters 4 and 14 of this thesis. Chapter 4: How effective is Apistan® at killing varroa? This shows that Apistan is not very effective at killing varroa, presumably because of resistance. It also shows that a single Apistan treatment resulted in the next treatment being significantly less effective, indicating strong selection for resistance. Chapter 5: Towards integrated control of varroa: comparing application methods and doses of oxalic acid on the mortality of phoretic Varroa destructor mites and their honey bee hosts. This shows that oxalic acid can be highly effective at killing varroa mites under beekeeping conditions in broodless hives in winter. However, varroa mortality is affected by application method and dose. In addition, bee and colony mortality and colony performance are also affected by application method and dose. The results of this chapter shows that sublimation is the best method, in that it gives greater varroa mortality at lower doses, and results in no harm to the colonies. In fact, colonies treated via sublimation had significantly more brood in spring that controls, and lower winter mortality, although this difference was not significant. Chapter 6: Towards integrated control of varroa: varroa mortality from treating broodless winter colonies twice with oxalic acid via sublimation. This shows that two treatments of 2.25 g oxalic acid via sublimation at an interval of 2 weeks in broodless honey bee colonies in winter result in greater varroa mortality than a single treatment, 99.6% vs. 97%. Making a second oxalic acid treatment was not harmful as the performance (frames of brood, queen and colony survival) of the twice-treated colonies over the next 4 months was not significantly different to the once-treated control colonies. Chapter 7: Towards integrated control of varroa: Efficacy of early spring trapping in drone brood. This indicates that trapping in drone brood in spring is probably not sufficiently effective to be able to control varroa populations on its own. It shows that trapping varroa in capped drone cells in early spring is not highly effective at controlling varroa. The first and second test frames of drone foundation removed 44% and 48% of the varroa, respectively. Chapter 8: Towards integrated control of varroa: Monitoring honey bee brood rearing in winter and the proportion of varroa in small patches of sealed cells. This shows that December is the month with the least brood. However, winter reduction in brood rearing varied among years and even in December some colonies still had sealed brood. Although the amounts of sealed brood were low, even a small patch of c. 500-600 sealed cells could contain 14% of the varroa in a colony. This will halve the duration of control provided by an oxalic acid treatment. Chapter 9: Towards integrated control of varroa: effect of variation in hygienic behaviour among honey bee colonies on mite population increase and deformed wing virus incidence. This shows clearly that hygienic behaviour reduces the one-year population growth of varroa in honey bee colonies by more than 50% and reduces the levels of deformed wing virus by more than 1000 times. Chapter 10: Hygienic behaviour saves the lives of honey bee colonies. This shows that hygienic behaviour saves the lives of honey bee colonies with shrivelled wings, a visible symptom of deformed wing virus that is considered a predictor of colony death. Over one year, only 2 of 11 colonies requeened with a non-hygienic queen survived, versus 13 of 15 requeened with a hygienic queen. Chapter 11: Hygienic behaviour by non-hygienic honey bee colonies: all colonies remove dead brood from open cells. This shows that all honey bee colonies are highly hygienic in response to dead or diseased brood in open cells. All larvae killed by freezing with liquid nitrogen and larvae with chalkbrood disease were removed. This was true even for colonies with low levels of removal of dead brood from sealed cells, which would be considered as non-hygienic colonies. Chapter 12: Removal of larvae infected by different strains of chalk brood and other fungi by hygienic and non-hygienic bee colonies. This shows that hygienic and non-hygienic honey bee colonies are highly hygienic in response to diseased larvae killed with different strains of fungus in open cells. Chapter 13: Hygienic behaviour in Brazilian stingless bees. This shows that the three stingless bee species studied (Melipona scutellaris, Scaptotrigona depilis, Tetragonisca angustula) all have high levels of hygienic behaviour, quantified as the removal of freeze-killed brood, in comparison to the honey bee Apis mellifera. In S. depilis there was considerable variation in hygienic behaviour among colonies, and hygienic colonies removed more brood affected by a naturally-occurring disease which we discovered and for which the causative agent remains to be identified. Chapter 14: First record of small hive beetle, Aethina tumida Murray, in South America. This reports the discovery of adult small hive beetles, Aethina tumida, in honey bee, Apis mellifera, hives in an apiary in Brazil, in March 2015. This is the first record for South America of this honey bee pest.

Bees provide important pollination services for crops and wild flowers, estimated to be valued at £120 billion to the global economy. However, declining bee populations have put these services in jeopardy. Pesticides are widely blamed, at least in part, for declines in both wild and managed bee species. Bees are exposed to dietary residues of pesticides when foraging on the nectar and pollen of treated bee-attractive crops. However, these residues are generally found at such low levels that it would not be feasible for a bee to ingest an acute lethal dose. Pesticides which exhibit time-reinforced toxicity could cause mortality to bees over an extended exposure period, though, as the damage they cause can increase exponentially over time. Currently, there is no test for time-reinforced toxicity included in bee risk assessments of pesticides. The overall aims of this thesis were to identify pesticides that exhibit time-reinforced toxicity and determine their effects on a range of demographically important sublethal endpoints in bees. Using a bioassay based on Haber’s Law, I identified fipronil as a pesticide exhibiting time-reinforced toxicity (TRT) in both the honey bee (Apis mellifera) and bumble bee (Bombus terrestris), from four widely-used candidate pesticides. Fipronil at field-relevant levels was found to significantly reduce the longevity and feeding of individual worker bumble bees and those in microcolonies. This nutrient limitation was postulated to be the cause of reduced fecundity of bumble bee microcolonies exposed to dietary fipronil at concentrations of 1 part per billion and less. The toxic effect of fipronil was dramatically increased when microcolonies were placed outside to forage for food, an effect documented by several other studies, and potentially due to an increase in metabolic rate from the need to fly. However, these effects were not observed in queenright Bombus terrestris colonies in the field. This disparity in effects may have been due to problems with exposure to fipronil rather than any possible resilience of colonies. The thesis findings highlight the need for time-reinforced toxicity testing in bees to be integrated into current risk assessment protocols for pesticides. My work in this thesis has provided validation for the use of the TRT bioassay in future risk assessments of pesticides. Current-use pesticides that exhibit TRT, in this case fipronil, pose a serious threat to both wild and managed bees, impacting on demographically important endpoints including feeding and reproduction. Further research, continuing on from the work in this thesis, is needed to ascertain the impacts of TRT pesticides at both colony and population levels. Determining the mechanisms of TRT pesticides will also be key to protecting bees from the danger they pose.

Bees provide important and economically valuable pollination services to agriculture and other ecosystems. Recent global honeybee declines have been attributed to pesticides, which can ultimately affect the overall functioning and survival of a colony. Various routes of exposure include contaminated beeswax, pollen and nectar. This thesis presents work which examines the presence, accumulation and levels of pesticides found within a number of honeybee related matrices and bumblebee bodies, with four main aims to this study. Firstly, determine which pesticides are contained within beeswax from around the UK. Secondly, monitor which pesticides accumulate in beeswax over a two year period. Thirdly, measure residual neonicotinoid levels in oilseed rape (OSR) nectar and pollen samples. Finally, quantify the levels of thiamethoxam and metabolite clothianidin in bumblebees, following feeding trial exposure, as part of a collaborative study. Analysis was conducted using gas chromatography–mass spectrometry (GC-MS) and quadrupole time-of-flight liquid chromatography-mass spectrometry (Q-TOF LC/MS), utilising the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction method. Bumblebee samples were extracted using a refined in-house procedure. Results evidenced apiculturally applied chemical treatments to be most likely found in beeswax samples whilst tau-Fluvalinate was most persistent and likely to accumulate in the hive, including foundation wax not exposed to such treatment. Varied levels of neonicotinoids were identified in hand-collected OSR nectar samples; and there require a greater level of analysis, to further understand the implications of these results on UK bees. No quantifiable levels were detected in pollen. Bumblebee analysis determined possible levels of exposure to thiamethoxam during feeding. This thesis provides the first known attempt of identifying pesticide presence and accumulation within UK beeswax, in addition to the levels within UK OSR nectar and pollen. The findings may have wider implications on the beekeeping community. Also presented are various methodologies suitable for future research.

Urban densification and a rise in human population call for greater investigation into how the urban-rural gradient can influence bees and their pollination services. This thesis aimed to further current knowledge by: (i) sampling bee assemblages along the urban-rural gradient in Birmingham, UK; (ii) increasing documentation of bee traits associated with pollen carryover; (iii) incorporating a trait-based analysis to bee assemblage change along the urban-rural gradient; (iv) testing whether the pollination services along the same gradient varied between land-use types and (v) investigating the provisioning and reproductive success of bees in the urban environment. This thesis supports previous evidence of species-specific variation by urbanisation and shows how trait composition and trait diversity are influenced by bee assemblage change along the urban-rural gradient. However, this recorded assemblage and trait variation appeared not to alter seed-set in Campanula glomerata between urban and rural areas. I also found that nutritional quality could play an important role in provisioning rate in the solitary bee \(Osmia\) \(bicornis\), with greater offspring produced in sites where more protein was found in provisioned pollen in urban areas. Furthermore, the inter-specific variation in pilosity (which could have an important role to play in pollen carryover and subsequent pollination) can be explained by body size and species’ pollen transport adaptation. From this work, I suggest trait based analysis could be a common framework for future studies to measure bee assemblage change between urban and rural areas. Moreover, this research builds on previous work which suggests that particular traits affect pollen transport and subsequent pollination, and that further detailed study could give clues as to how changing bee assemblages could influence pollination.

Nosema ceranae, a microsporidian, has been given much attention in recent years as it has been linked with Colony Collapse Disorder (CCD), which leads to the sudden deaths of honey bee colonies. It has been described that many pathogenic organisms secrete virulence factors in order to hijack its host`s cellular functions, but in most cases the underlying mechanisms of this process still remains to be deciphered. Cornman et al. (2009) have identified in N. ceranae a list of putative effector proteins (called secretome) destined to be secreted into the host, and I have taken this list for further investigation using a bioinformatical and experimental approaches. The principal aim of this project was to generate a N. ceranae ORFeome for genes predicted to be secreted, elucidate the function of effector candidates important for N. ceranae biology and/or pathogenicity, as well as to investigate any interactions between N. ceranae proteins and its host utilising two eukaryotic model organisms, budding yeast, S. cerevisiae, and fruit fly, D. melanogaster. A library of S. cerevisiae strains expressing N. ceranae proteins was generated utilising the Gateway® technology, and phenotypic and localisation screens were undertaken to investigate the N. ceranae secretome. Two N. ceranae ORFs, NcORF-15 (NcORF-02039) and NcORF-16 (NcORF-01159) encoding a putative thioredoxin and a hexokinase, respectively, were subjected to yeast complementation assays in order to assess their catalytic activity. NcORF-15, the putative thioredoxin, was able to rescue the sensitive phenotype of S. cerevisiae Δtrx2 under oxidative stress, whereas NcORF-16, the putative hexokinase, did not complement YSH7.4-3C, a triple knockout lacking hexokinase activity. A third N. ceranae effector candidate NcORF-4 (NcORF-00654), a putative proteasome subunit, was investigated for its nuclear localisation and protein interactions in both S. cerevisiae and D. melanogaster.

Paenibacillus larvae is the causative agent of American foulbrood (AFB), a damaging disease of honey bees (Apis mellifera) with a global distribution. AFB infects the honey bee larvae through spore-contaminated larval food and once infected the larvae will die within twelve days. AFB infection leads to the eventual death of the honey bee colony. In many countries the best control method is thought to be the destruction of the colony, to destroy the hardy, infectious spores. Therefore infection nearly always leads to the death of the colony. In the UK cases of the disease have decreased in recent years due to statutory control methods, however sporadic outbreaks occur each year. Many advances have been made in our knowledge of the mechanisms of infection by P. larvae in recent years however, a high resolution, standardised method of strain typing is required to track disease spread and understand outbreak sources. This thesis describes the development of the first multilocus sequence typing (MLST) scheme for P. larvae. MLST is the gold standard for pathogenic bacteria typing. It is based on the sequencing of sections of 6-10 housekeeping genes. MLST is standardised, as primer and allele sequences can be made available for other researchers. The new MLST scheme was used to describe previously undetectable patterns of distribution at a global level as well as at a national level. Humans and bees are implicated in the movement of the disease over different spatial scales. Using the MLST scheme a diverse group of isolates were selected for whole genome sequencing. For the first time multiple genomes were compared within and between genotypes. The ability of the MLST scheme to describe relationships amongst sequence types (STs) was tested by comparing phylogenies based on core genes and MLST sequences. I describe the discovery of seven plasmids in four STs previously unknown to harbour plasmids.

The PhD work aligns technological opportunities with self-selecting motivated participants, investigating their desire to monitor wildlife within their custody. It used an ethnographic and user- centred design approach with amateur beekeepers. The work built reciprocal interest in data which users could gather from self-assembled monitoring tools. This PhD explores the relationship between Open Design and Citizen Science, testing it ‘in-the-wild’ through the Bee Lab kit. The development of the kit and territory research was carried out in close collaboration with a local beekeeping community based in the South East of England. The work engaged with the British Beekeepers Association (BBKA), a Citizen Science stakeholder and technology provider Technology Will Save Us (TWSU), informing the project at each stage. The PhD territory was highlighted in scoping design workshops with the public (Phillips. R, Baurley. S, Silve. S) and developed into: cultural probes deployed nationally investigating beekeepers’ ‘making’ activities (Phillips. R, Baurley. S, Silve. S 2013b), ethnographic studies identifying beekeepers’ product creations and re-appropriations for beekeeping praxis, participatory design workshops establishing lay users’ ‘technologically enabled conversations with bees’ (Phillips. R, Ford. Y, Sadler. K, Silve. S, Baurley. S 2013), technology kit assembly workshops testing kit design and competence of lay users (Phillips, Blum et al. 2014), and mental models of creating instructional content (Phillips, Robert., Lockton, Dan., Baurley, Sharon & Silve, Sarah 2013). The Bee Lab Kit: activities engaging motivated lay users in the use of open technologies for CS activities Page 2 of 265 The creation of a repeatable Open Design/Citizen Science model based upon the live testing from the Bee Lab project appendix (O) Open Design Standards (paper pending publication) appendix (K) The project worked with Citizen Science Vendors, Sussex Wildlife Trust and Cornell Laboratory of Ornithology, ascertaining the framing of Open Design/Citizen Science projects through a design toolkit. The design toolkit invention and testing was carried out with conservation organisations (Phillips, R & Baurley, S 2014) and technology kit deployment ‘in-the-wild’ with end users (Phillips, R., Blum, J., Brown, M. & Baurley, S 2014). Finally, the work identified the motivations of the individual stakeholders within the project.

This thesis looks at the role of wild pollinators in providing services to crops. Two data chapters (2 and 3) are accompanied by a modelling chapter (4) which build on the findings of the field studies. The thesis ends with an overview of the trends in pollinator populations and how these relate to the needs of farmers in the UK (chap-ter 5). It is often assumed that commercial pollinators are appropriate substitutes of wild pollinators on farms; however this view neglects the differing roles that particular pollinator taxa might play in providing pollination services. For example, crops with a long growing system may require multiple pollinators to ensure pollination throughout the season. Strawberries in Scotland have an extremely long growing season, flowering from April to August. Chapter 2 presents a study showing season-al complementarity between different pollinating taxa across strawberry farms in Scotland. Pollinators of strawberries also differed in their responses to weather pa-rameters indicating that preserving multiple pollinator taxa could ensure yields un-der different weather scenarios. The requirements of a long-growing season and ad-verse weather may be specific to strawberry production in Scotland, but the valua-tion of multiple taxa can be generalised to systems with differing needs, and also to different ecosystem services. Wild bees are not only valuable for providing complementary services to commercial pollinators, but are also valuable in the longer term as it is unknown whether com-mercial pollinators will be available in the future. There are threats to the supply of honeybees which have already triggered price rises; such supply shocks could force farmers to leave production or to seek other ways of providing pollination, including supporting wild pollinators. However farm management pressures, in particular pes-ticide use, could threaten the ability of wild pollinators to continue to support crop production. The interplay of pesticides and pollination is discussed in chapter 3 and 4. Chapter 3 presents an experiment undertaken on soft-fruit farms which had and had not used the neonicotinoid, thiacloprid, and shows that nests exposed to thia-cloprid had higher worker mortality, and lower male production than those at con-trol farms. This has implications both for pollination services now, as worker mor-tality will reduce the number of bees visiting farms, and also for the maintenance of future pollination services through decreased reproductive capacity of exposed nests. Chapter 4 uses a theoretical model to link pesticide use and habitat use to pollina-tion services, and shows that the use of commercial pollinators could mask the de-cline in wild populations, making local extinctions more likely. Chapter 5 sets out the status and extent of pollinators in the UK, along with popu-lation trends, trends in habitat and trends in pesticide use to provide an overview of how well pollination services are likely to meet the ongoing needs of crop farmers.

Parasitoids play a fundamental role in the regulation of herbivore pests in natural settings. Flower resources can be used to provide natural enemies with suitable food sources that are otherwise lacking in modern agro-ecosystems, in order to enhance biological pest control. However, the introduction of flower resources can also enhance the fitness of the pests. This thesis investigated the potential of floral resources in enhancing the biological control of the cabbage moth Mamestra brassicae (L.) (Lepidoptera: Noctuidae) by its main parasitoid Microplitis mediator (Haliday) (Hymenoptera: Braconidae). A thorough review of available data showed that most parasitoids strongly depend on adult feeding for survival and that some flower species are selective, i.e. they only enhance the fitness of the parasitoids and not the pests. I performed laboratory experiments to identify selective flower species that enhance the fitness of M mediator, without benefiting its host, M brassicae. Longevity and parasitization rates by M mediator increased significantly with Centaurea cyanus, Fagopyrum esculentum and Vicia sativa. Longevity and fecundity of the pest were not affected by the plant species tested. I further studied the ability of M mediator to locate extrafloral nectar of C. cyanus. Female M mediator showed an innate attraction to olfactory cues of floral but not extrafloral nectar of C. cyanus. The most promising plant identified, C. cyanus, was assessed with regard to its effect on parasitization rates of M brassicae and crop yield in a two-year large-scale replicated field experiment. Parasitization rates of M brassicae significantly increased in the treatment with C. cyanus, resulting in a significant increase in the marketable cabbage weight in this treatment in 2009. These results emphasize the importance of plant screening in identifying selective plant species and underline the potential of flowering companion plants as new habitats, resulting in an increase in the success of biological control programs.

The detection and control of American Foulbrood (AFB) is made more challenging due to a lack of evidence regarding the virulence mechanisms employed by this honeybee pathogen. Whilst incidence of this pathogen within the UK has recently declined, ~100 colonies were identified as infected with AFB in 2011 (to end of September), so AFB should still be considered a serious threat to honeybee health. It is known that within the species many phenotypes exist, and the infection caused by the phenotypes differs greatly. This PhD thesis presents several advances towards a greater understanding of the intra-specific differences occurring within the species. Chapter 2 evaluates the use of 16S rRNA sequencing as a method of Paenibacillus larvae identification, as well as exploring the use of this ribosomal subunit for differentiation of the species. The sequencing of two housekeeping (purH and PyrE) genes assesses the potential of a Multi Locus Sequence Typing (MLST) method, as a means of subspecies differentiation. Chapter 3 assesses what can be inferred from use of Enterobacterial Repetitive Intergenic Consensus (ERIC) sequence fingerprinting, with regards to prior knowledge genetic differences. Lateral Flow Devices (LFDs), a commonly used diagnostic tool, are tested to ensure P. larvae isolates representing all 4 ERIC types are detected. In Chapter 4 an in-vitro honeybee rearing method is employed to observe the correlation between proteolytic activity of isolates and in-vitro virulence. The method is applied to a wider range of reference isolates, to observe the intra-species differences existing. The ability to produce large numbers of viable spores is explored as a potential difference existing between ERIC types I and IV. Whole genome shotgun sequencing is used in chapter 5 to perform comparative genomic studies on 4 P. larvae isolates also utilising 646 contigs from a previous sequencing project. The possible presence of plasmid DNA is explored, through GC content analysis. The genetic basis of a sporulation phenotypic difference is examined by BLAST analysis of orthologous genes. In Chapter 6 the findings of this thesis are discussed in more detail, and potential areas of further study are identified.

Once every three, four or even seven years, the Southeast trade winds which blow west-ward across the tropical zone of the Pacific Ocean, from the shores of South America towards the Asian land mass, weaken and sometimes even reverse their direction. This phenomenon is known as El Nino. Conversely, the climatic condition known as La Nina is characterised by unusually cold ocean temperatures in the equatorial Pacific, as compared to El Nino. Global climate anomalies associated with La Nina tend to be opposite to those of El Nino. A study of shrimp culture in Ecuador was carried out to analyse the temporal changes in pond water quality, phytoplankton composition and diversity, and bacterial composition and diversity in the intestines of cultured Litopenaeus vannamei in Ecuador. These parameters were studied in relation to their impact on the growth, survival and production in a semi-intensive shrimp culture farm situated in the Chone River Estuary, Ecuador. Five culture periods were studied during the climatic events of El Nino, La Nina and transition periods (1996 to 1999 ). Shrimp were stocked in ponds at 10 PL/m2. Pond management included pond drying, inorganic fertilisation, and feeding with a commercial pellet twice a day. The physicochemical characteristics of the pond water and the phytoplankton and bacterial counts were estimated at intervals of 7-15 days of culture during each period of study. The concentrations of nitrite, nitrate, sulphide, ammonia, pH and suspended solids in the pond water in all ponds during the five culture periods fluctuated within ranges considered compatible with shrimp farming. Phosphorus, silica, temperature and salinity, however, showed significant differences during the five periods of shrimp culture, reaching sub-optimal levels during some culture periods. The species composition and diversity of phytoplankton was different during El Nino, La Nina events and transition periods, with a decrease in the diatom community and an increase in the cyanophytes algae community associated with changes in nutrients and nutrient ratios, and temperature, salinity is discussed. A low diversity of bacterial genera with a predominance of Vibrio spp., particularly V. harveyi and V. parahaemolyticus, was observed in shrimp intestines during disease outbreaks in the transition and La Nina periods associated with significant environmental changes in temperature and salinity. Shrimp performance was significantly different between El Nino, La Nina and transition climatic periods. Survival, feed conversion ratio and yield were better during El Nino periods because of the positive effects of higher pond water temperature and salinity (29°C and 28 psu) on the shrimp stocks.

Sacbrood virus causes changes in honeybees which may be summarized as follows: A. Larvae 1. Fewer protein granules than usual form in the cytoplasm of the fat body cells of growing larvae. 2. The protein reserves that form in the fat body cells, and the cells themselves, remain intact when the larvae become mature, whereas in healthy larvae they are broken down. 3. The endocuticle of mature larvae remains undigested, when the last larval skin is being shed, and so prevents ecdysis. B. Adults 1. The protein granules in the cytoplasm of the fat body cells and the proteinaceous secretory globules in the cytoplasm of the hypopharyngeal glands disappear sooner than. usual. 2. The lives of bees are decreased to about three weeks, the same length of life as of bees deprived of protein (pollen). 3. Worker bees are more susceptible to chilling than usual, probably because of their decreased metabolism, an effect also caused when healthy bees are deprived of protein. 4. Young worker bees fail to eat pollen, to attend the queen or drones, and to rear brood. 5. Young worker bees and drones try to fly and worker bees start to forage sooner than usual. 6. Foraging worker bees do not collect pollen, or collect very little. 7. The eggs of unmated queens mature sooner than usual. 8. The mitochrondria in the brain of drones appear to be damaged. The changes caused by sacbrood virus in adults summarized in (4), (5), (6) and (7) above, are the same as those that follow when healthy individuals are anaesthetized with carbon dioxide, and are equivalent to changes that occur in senile individuals, possibly activated by accumulated acid metabolites. Most of these changes are probably important in preventing rapid spread of sacbrood in nature.