Successful conservation of British biodiversity largely depends on privately owned agricultural land that covers over 75% of Britain's surface area. Several centuries of traditional management for land uses like hunting and shooting have shaped the British countryside. However, agricultural intensification since Wodd War II has reduced habitat quality, and resulted in biodiversity losses, for example of woodland and farmland birds. More recently, agri-environment schemes (AESs) have sought to redress these losses, but have not yet realised wider benefits because of adopted inappropriate prescriptions and/or poor execution of these prescriptions. However, many landowners who shoot gamebirds produce high quality habitat that also benefits wider biodiversity. Additional benefits generated by gamebird shooting include job creation, financial benefits for local businesses, and social cohesion among rural c0l111nunities. Nevertheless, some opponents wish to ban gamebird shooting or introduce regulations. Consequently, many lowland shoots have changed some practices, in particular reducing the numbers of reared and released birds. This thesis investigates the social attitudes of those who shoot, and the biodiversity benefits and financial viability of these changed practices on a lowland pheasant shoot in Kent. Focal group discussions showed that the four main stakeholder groups placed different values on gamebird shooting, although each group recognised many wide reaching benefits. Equally, discussants emphasised the need to accept change to assure the future of gamebird shooting. Surveys around a new land management regime designed to increase wild pheasant numbers on a commercial reared shoot showed increases in pheasant brood density and average brood size. This highlighted the feasibility of increasing wild game productivity, even among large numbers of reared gamebirds, through habitat creation, modified gamekeeping and supplementary feeding. Pheasant productivity was significantly related to gamekeeping effort, spring pheasant population composition, and the release of reared gamebirds. The effects of the new land management regime on wider wildlife were mixed. Butterfly numbers increased and were greater in number than were observed in populations at a site under conventional farm management with no AES. Bumblebee numbers did not increase and were no different to those at the conventionally farmed site. This indicated that grass margins created through the new regime increased habitat quality only for certain species groups. Numbers of butterflies and bumblebees were similar to those on well-established shoots that are predominantly or completely wild, indicating that large numbers of reared gamebirds did not affect butterfly and bumblebee numbers. The number of butterflies and bumblebees was positively related to the cover of flowers and herbs, suggesting that the seed mix sown in field boundaries is important in determining the populations of these two species groups. The number of insects important as chick food items increased significantly in the grass margins sown under the new regime, showing that these habitats successfully provided rich feeding areas for wild gamebird broods. The grass strips contained more insects than conventionally cropped field edge, highlighting the importance of alternative habitat areas in wild gamebird productivity. Densities of songbirds increased under the new regime, and compared to those on well-established shoots that are predominantly or completely wild. Songbird populations were significantly influenced by gamekeeping effort and the amount of alternative habitat created by field boundaries and AES prescriptions. The willingness-to-pay survey indicated that shoot owners would lose significant revenue, should the release of reared gamebirds be banned in the future. As many shoots generate little or no money for their owners, or are even run at a loss, it was concluded that a future ban on released birds would result in the closure of many lowland shoots, and the loss of the varied social and biological benefits generated by gamebird shooting.

Macroparasites have a central place in wildlife ecology because they have the potential to regulate host populations through effects on reproduction and/or survival. However, there remains a paucity of studies investigating parasite-host relationships in .wild animals. This thesis focussed on the transmission and impact of a gastrointestinal nematode of Svalbard reindeer (Rangifer tarandus platyrhunchus), Marshallagi marshalli. The overall aim of the thesis was to test whether M marshalli is transmitted during the Arctic winter and to quantify the impact of over-winter parasitism on the fitness of Svalbard reindeer. To do this, parasite burdens needed to be manipulated during winter, at a time when reindeer cannot be caught. Therefore, a delayed-release intra-ruminal bolus system was developed, to enable administration of the bolus up to six months before reducing worm burdens. By removing parasite burdens at the start of winter and monitoring re-infection rates of larval and adult nematode stages, the over-winter transmission strategy of M marshalli was experimentally demonstrated. Further laboratory-based experiments provided support to the hypothesis of a one-year time delay in the production of eggs to the recruitment of parasites to the host population. They also demonstrated that eggs and larvae can withstand exposure to sub-zero temperatures. Contrary to expectation, a long-term, individual-based, capture-recapture experiment revealed no significant differences in body mass and pregnancy rates between animals treated with anthelmintics overwinter and non-treated animals, suggesting that nematode infection during winter does not significantly affect fitness of Svalbard reindeer. This thesis provides base-line data on a parasite-host interaction in the Arctic and may contribute to a better general understanding of the circumstances and environments in which parasites may negatively impact on host fitness.

The European eel, Anauilla anauilla (L.) is widely distributed throughout European continental waters. However, there is much concern about the conservation status of the species and the long-term sustainable exploitation of stocks. Current European Commission (EC) International Council for the Exploration of the Seas (ICES) advice remains in place: ‘to reduce anthropogenic impacts (on A. anguilla) to as close to zero as possible’. In Northern Ireland A. anguilla are considered ubiquitous to many freshwater and brackish water habitats and are harvested commercially from the Lough Neagh / River Bann catchment. Through active stakeholder engagement and consultation - Lough Neagh Fishermans Cooperative Society (LNFCS) and the Agri-Food and Bioscience Institute (AFBI)-a number of key aims were identified, that formed the basis of this thesis. Specifically, we aimed to: 1. Establish the baseline biocontaminant levels (heavy metals, PCDDs, PCDFs and dioxin-like PCBs) in yellow phase eels. 2. Estimate fecundity, body condition and health parameters for silver phase eels migrating from Lough Neagh. 3. Assess the broader distribution of A. anguilla throughout catchments, not yet formally tested for the presence of the species. 4 Determine the prevalence of the swimbladder parasite. Anguillicola crassus and the where present, assess the ecological implications of infection on growth, fat content and body size. 4. Develop a combined approach using otolith Sr:Ca microchemistry and stable isotopes for estimating habitat residencv profiles in A. anguilla. 5. To characterise the physiology and ecology (age, growth, trophic position, body size, estimated fat content and lipid composition) of eels exhibiting different habitat residency profiles.

Small-scale fisheries (SSF) are poorly documented, yet 90% of the 120 million employed in capture fisheries work in the SSF sector and >1 billion people globally rely on fish as an important source of protein. There is a lack of data on the status of the majority of fisheries in Madagascar owing to the difficulty in surveying the vast coastline and large number of small-scale fishers. In Madagascar, marine turtles and elasmobranchs are important culturally and as sources of income and food for many small-scale fishers. However, very little data exist on the status of these two animal groups. The five chapters of this thesis intend to increase our understanding of the status of marine turtles and elasmobranchs in Madagascar. This is achieved through the assessment of the fisheries, legislation and in the case of turtles, the nesting population. I also document community-based methods for monitoring fisheries and marine turtle nesting, that are easily replicable for gathering data across remote regions. Results show that the turtle fishery in Madagascar appears to have remained at the same level since the 1970s, despite being illegal since the 1990s, with landings estimated to be approximately 10,000 to 16,000 turtles.year-1. To further contextualise the take of turtles in Madagascar, by carrying out a global review, I estimate that the worldwide legal take in turtle fisheries to be over 42,000 turtles.year-1. Contrary to reports from fishers, actual numbers of elasmobranchs (the majority of which are sharks) taken by the traditional (non-motorised) fishery has not declined. Results support previous reports that fishing effort has increased, as well changes in fishing gears, to account for declining catch per unit effort (CPUE) to maintain shark landing numbers. Furthermore, the size of some shark species has significantly declined, even across this study. Community-based turtle nesting monitoring and protection in western Madagascar revealed a small, yet potentially significant, nesting population. Across the 17 current nesting sites recorded, the majority of nesting populations in Madagascar have <50 nests.year-1. A further >40 historic nesting sites were recorded. Community-led monitoring methods not only helped to fill a data gap, but were also found to reduce loss of nests through human disturbance. Misinterpretations, poor enforcement and gaps in current legislation mean that both marine turtles and elasmobranchs are effectively unprotected from overexploitation. This thesis provides recommendations for improved legislation and management of both groups of species and demonstrates that participatory monitoring methods can not only reduce data deficiency, but enhance locally-led management and protection, and increase Madagascar's capacity for improved management and conservation.