The construction of a partial exclusion amenity barrage across the lower estuary of the River Tawe, South Wales, was completed in 1992. The structure includes a pool and weir fish pass consisting of 16 pools interlinked by deep notches in alternately downstream and cross facing traverses. Modifications to the fish pass weirs were carried out at the end of June 2000 in order to address the problem of excessive turbulence within the pools. The primary aim of this thesis was to examine the effectiveness of the modified fish pas under a range of environmental conditions. Underwater video was selected as the most suitable method for monitoring fish use of the pass and a system was designed and installed below the fish pass exit notch. The effects of time of day, tidal state, river flow volume and water quality on fish use of the modified pass were examined. Diel and tidal rhythms appeared to have the greatest impact on fish movements. The majority of fish exited the pass during daylight, supporting the hypothesis that fish utilise visual cues to negotiate obstacles. The timing of movement during tides which completely inundated the fish pass suggested that fish were using the rising tide to aid ascent, however a greater number of fish used the pass during non-inundating tides when this was main route past the barrage. Fish use of the pass appeared to be stimulated between river flows of 3.00 – 6.99 m³ s^-1 and 10 – 10.99 m³ s^-1, and there was evidence that salmonids use of the fish pass increased in response to changes in flow. Dissolved oxygen concentrations remained above levels which would affect the swimming ability of fish, although oxygen supersaturation may potentially cause periodic problems.

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Rapid industrialisation of livestock farming since the 1950s has been accompanied by public and legislative concern directed towards a range of issues, including food safety and the negotiation of risk, and also the ethics attached to the care, slaughter and commodification of unprecedented numbers of animals in large scale production. Drawing on ethnographic data generated by long term fieldwork on intensive pig units, the thesis foregrounds the firsthand accounts of stockmen to explore in detail how pigs are produced now, and the reciprocal ways that pig production ‘makes’ people. Although these processes take place out of public view, pigs and people are nevertheless produced in response to external expectations, imaginations, and markets. The thesis shows how these influences, farmers’ attitudes, and the methods of pig production itself, are currently undergoing revision and change. By doing so, the thesis resists the idea that industrialisation and globalisation always and everywhere result in a flattening of space and time, arguing instead that what is produced is neither completely old or new, but rather an articulation between traditional forms of animal husbandry and new varieties of knowledge, technology and embodied practice.

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