Medusozoan jellyfish (Classes Scyphozoa and Hydrozoa) have gained a degree of worldwide notoriety in the last fifteen years, particularly as anthropogenic influences such as climate change and overfishing push some ecosystems toward their advantage (Lynam et al. 2005, Purcell and Arai 2001, Purcell et al. 2007, Purcell 2012, Flynn et al. 2012, Dawson et al. 2014). Accordingly, both the lay and scientific media have paid a good deal of attention to jellyfish bloom phenomena and their impacts on human activities, but the bulk of this attention has been devoted to larger, visually obvious species of Class Scyphozoa. Only recently have their smaller cousins, the hydrozoans, come to be recognized as potentially problematic. This thesis examines population ecology of hydrozoan medusae (hydromedusae) and their implications for salmon aquaculture in Scotland. My review of available literature has found hydrozoans to be a recognized - though under- studied - problem for Scottish salmon (Chapter 1, Prospective monitoring of hydromedusa populations at salmon aquaculture facilities). Typically, hydrozoan populations at salmon farms have been discussed in the scientific literature only in the context of extremely dense visible blooms or in the wake of major mortality incidents. This retrospective, rather than prospective, approach has left a dearth of knowledge pertaining to hydromedusan interactions with farmed fish, with both fish welfare and industry economics vulnerable to future blooms. This thesis sought to build a basis for the goals of prediction, avoidance, and mitigation of harmful hydrozoan jellyfish blooms. First and foremost, this required the development of a prospective time-series dataset of hydromedusan occurrences at salmon farms (Chapter 2, Bacterial genera biodiversity in three medusozoan species in Shetland). To this end, four farms were recruited as participants across a three-year survey. Weekly plankton tow-based sampling at these sites identified which hydrozoan species could be expected to produce blooms, the seasonality of such blooms, and the pathological sequelae that could be expected in salmon after exposure to such blooms. Following one particularly dramatic bloom, a spike in gill pathologies in salmon was observed, followed by a spike in overall mortality and the eventual loss of up to £2.5 million value as the fish were humanely culled. This survey also demonstrated that hydromedusan blooms are usually spatially and temporally patchy, limiting the opportunities for geographically-encompassing predictive power. Instead, individual aquaculture facilities may require site-specific risk assessment and planning frameworks to monitor and cope with blooms. Potential methods for continued basic monitoring and a mitigation strategy based on minimizing contact between fish and high-density blooms are suggested. A second mitigation goal examined the theory that medusae may act as vectors for microbial pathogens, particularly Tenacibaculum maritimum (Ferguson et al. 2010, Delannoy et al. 2011; Chapter 3). Sampling methods designed to target T. maritimum were employed with the aim of determining its distribution and role as a symbiont in various life stages of medusozoan species. While T. maritimum itself was not observed, a number of other fish pathogens were found in close association with several species. This included Aeromonas salmonicida, known to cause furunculosis in aquaculture of both salmon and trout (Nomura et al. 1992). Further work is required to piece together the nature of these associations. Finally, Chapter 2 identified a particular hydrozoan genus, Obelia, as a likely significant contributor to blooms at salmon aquaculture sites. One of its species, O. geniculata, has a widely distributed and well-recognized benthic colonial life stage (called the hydroid stage) in Scottish nearshore sublittoral environments. In attempting to sample these hydroids from previously well-colonized sites in Shetland in late 2012, it became apparent that a severe local reduction in the benthic population was taking place. This allowed for the opportunity to study phylogeographic population structure - i.e. the boundaries of its gene pool(s) in Scottish waters and its potential for dispersal during one seasonal reproductive period - using a molecular study of the mitochondrial cytochrome oxidase subunit I (mtCOI) gene (Chapter 4, Phylogeographic analysis of Obelia geniculata populations in the north of Scotland). In sampling immediately after the observed dieback, O. geniculata was found to follow a south-to-north pattern of genetic grouping, as well as a confirmed dieback. However, this pattern disappeared in samples collected after the population had recovered, probably due to the immigration of genetically novel individuals. This finding, in conjunction with the spatial-temporal patchiness found in the medusa bloom stage, suggests the importance of the larval stage as the primary stage for dispersal in the plankton. This study was also able to compare present population genetic data with a set of O. geniculata mtCOI data collected between 1998 and 2002. The combined data potentially show a high degree of mixing across a number of North Atlantic regions, including Icelandic and North American sites. Further investigation will be required to discern whether this pattern is temporally based (i.e. artefact of 15 years' elapsed time in opportunities for population mixing), or whether ecological, anthropogenic, or combined mechanisms are facilitating rapid transport of propagules to yield a well-mixed population. Further work in refining prediction and mitigation is still needed, as are effective veterinary interventions in the event of blooms. Continued study into the ecological patterns of colonization and dispersal may help to minimize exposure to blooms, by helping to assess site-based risks. This research forms the basis for such studies into hydrozoan interactions with salmon farms in Scotland, and how the industry might seek to minimize their impacts.

The issue of sea lice (Lepeoptheirus salmonis and Caligus clemensii) transfer from salmon farms to wild salmon is a controversial topic in British Columbia (BC). A series of sea lice epizootics (four in five years) on juvenile chum (Oncorhynchus keta) and pink (0. gorbuscha) salmon in the Broughton Archipelago (BA), an area with the highest density of salmon farms on the west coast, have caused significant concern among conservationists, local First Nations, and the general public over the possible impacts of salmon farms on wild salmon. Key to the debate has been a lack of data on ambient sea lice infection rates on juvenile salmon in the absence of the influence of salmon farms. This work represents one of the first attempts to empirically examine ambient sea lice infection rates on juvenile salmonids. Objectives were to test hypotheses including: geographic variability is a significant factor in sea lice population dynamics, ambient sea lice infection rates on juvenile salmon are low, juvenile salmon susceptibility to sea lice infection, and the influence of salmon farms on ambient sea lice infection rates. Over a three year period, samples of juvenile chum and pink salmon (n=13.874) were collected using a beach seine net in the central coast of British Columbia (Klemtu/Bella iv Bella), a vast area with limited salmon farming activity. and with geography that allowed for simultaneous assessment in the same region of the natural interaction between sea lice and juvenile salmon and the influence of salmon farms on the interaction. Sampling was also conducted in other areas without salmon farms (Southern Gulf Islands: n=3847) and with salmon farms (Broughton Archipelago; n=3911). The results of the field experiments were also used in conjunction with laboratory experiments to examine the susceptibility of juvenile chum vs. pink salmon to infection by sea lice. The ambient lice infection rates for juvenile chum and pink salmon were up to 32% prevalence, less than one louse per fish and less than two lice per gram (prevalence: 2.0 (1.0) - 32.0 (19.0), mean lice per fish: 0.02 (0.01) - 0.67 (0.22), mean lice per gram: 0.56 (0.08) - 1.93 (0.13)). This result was found to be consistent across geographic areas with no salmon farming activity suggesting that geographic variability was not a significant factor in the natural interaction between sea lice and juvenile salmon. Salmon farms were found to strongly influence the relationship between sea lice and juvenile chum and pink salmon. Sea lice infection rates of juvenile salmon collected near salmon farms were significantly higher than non-salmon farming regions ranging from 3 - 150 times higher in the BA and from 2 - 14 times higher in the Klemtu region. Infection levels near salmon farms were variable in intensity from year to year. The extent to which the sea lice-salmon relationship was affected by salmon farms was dependent on farmed species, farm location, within year variability in fish size, and the scale of salmon farming activities within the region. The results from the laboratory and field studies demonstrate that juvenile chum salmon were more susceptible to infection by sea lice than juvenile pink salmon. However, the exact mechanism for the observed differences was not identified. Possible reasons for the observed differences could be related to genetically determined susceptibility, fish mucous differences, lethal lice infection tolerances. or other factors not examined. The results of this study suggest that the elevated sea lice infection rates observed in the BA and other areas present a significant risk to the health of wild salmon and that salmon farms are the most likely cause based on the biology and ecology of sea lice. In order to better understand the potential for salmon farms to affect wild salmon populations, it is suggested that investigations into farm level sea lice contributions be conducted in the BA and other areas where salmon farms operate. In addition, investigation into the lethal lice infection rates for juvenile salmon at early marine life size should also be conducted.

Salmon aquaculture is a controversial industry in British Columbia (BC). First Nations in BC have expressed concerns about possible contamination of traditionally harvested foods by waste from salmon farms. Trace elements are released from farms via waste feed and feces, as well as leaching from netpens and antifouling paints. In addition to elemental analysis, farm waste can also be traced using stable isotopes of nitrogen and carbon. Due to the use in salmon feed of protein and oil derived from pelagic marine fish, farm waste is typically enriched in heavier isotopes of nitrogen and carbon when compared to marine particulate organic matter. in partnership with First Nations from Ahousaht, BC, I investigated these effects by determining the concentrations of three metals and one metalloid in salmon feed, sediment and Manila clams Venerupis philippinarum from six sites in Clayoquot Sound, on the west coast of Vancouver Island, BC. Samples were collected from three sites near salmon farms and three reference sites in four different months spanning the traditional clam harvesting season. The results suggested that salmon feed continues to be a source of trace elements in the marine environment; however, salmon farms did not appear to be elevating concentrations in nearby clam tissue and sediment. Different environmental conditions between sites may have exerted a greater influence on elemental concentrations than farm-derived elements. Contrary to findings in earlier studies, the nitrogen signature of salmon feed was not enriched relative to marine particulate organic matter and was not a useful tracer of farm waste. This may have resulted from the reformulation of salmon feed to include greater quantities of protein and oil from terrestrial rather than marine sources. Due to the importance of Manila clams in First Nations' diets, the high density of salmon farms in the study area, the likelihood of ongoing feed reformulation, and the propensity for contaminants to accumulate over time, ongoing monitoring of sediment and bivalves in the area would be advisable.

Aquaculture has been a way to produce fish as a protein source for thousands of years and over the past decades aquaculture has been the fastest expanding animal-based food sector in the world. This study focused on quantifying the flows of nitrogen and phosphorus in Atlantic Salmon farming and compared traditional open net farming with a more recent technique, land based recirculating aquaculture system (RAS). The aim was to quantify the difference in emissions of nitrogen and phosphorus between the two types of farming and to quantify the amount of nutrients that could be reused from the respective fish farm. Data were obtained from reports, scientific publications and an application for environmental permit (EIA) for the case Smögenlax Aquaculture AB. The same feed input and salmon output were assumed in the two systems and a substance flow analysis was used to quantify the flows of nutrients. The amount of produced salmon and fish feed/year were taken from Smögenlax Aquacultures EIA. The results showed that a RAS-based Salmon farm emits only 6 % of the nitrogen and 5 % of the phosphorus emitted to the recipient waters in comparison to an open net farm. RAS-based salmon farming also enables the reuse of 19 % more nitrogen and 47 % more phosphorus than an open net farm by using sludge and fish offal from the farm to create biogas and biofertilizers. RAS is still evolving to provide possibilities for large scale salmon farms on land to be both cost and environmental efficient and may in the future be the most common way to farm Atlantic Salmon.

Neoliberal economists argue that the market provides the most efficient mechanism to address externalities. Theoretically then, the market value of a commodity should show a correlation with any changes in social and ecological performance. Alternatively, if the social and ecological costs of production are being externalized (not addressed by the market) then it is expected that the social and ecological costs of production would not be reflected in the market price. This study examined the extent to which social and environmental costs are externalized by the salmon farming industry and, by extension, to what level social and ecological impacts are reflected in the market, if at all. The salmon farming industry represents a classic example of how a relatively new industry functions within the confines of the current economic climate and was assessed to examine whether social and ecological impacts are reflected in the market. A novel tool called the Global Aquaculture Performance Index (GAPI) has been developed that addresses both the need for a quantitative measure of social and ecological performance and a tool that informs where policy is best directed to alleviate the impact of externalities. In applying the GAPI method, the market price for farmed salmon was not found to be correlated with changes in social and ecological performance and it may be assumed that these costs are externalized. GAPI provides a quantitative, performance based assessment of the salmon farming industry while the indicators of social and ecological performance provide clear starting points to improve salmon farming through a policy based context.

Cette recherche vise à mieux comprendre les frictions occasionnées par la présence de l’industrie salmonicole sur les territoires ancestraux des nations kwakwaka’wakw et nuu-chah-nulth de l’île de Vancouver. Alors que le contexte à l’étude a déjà fait l’objet de nombreuses recherches, la question des rapports entre les humains et les poissons fut généralement mise de côté. En ce sens, le présent mémoire cherche à combler cet important fossé. J’avance la proposition selon laquelle l’introduction de l’industrie salmonicole sur les territoires autochtones de l’île de Vancouver serait instigatrice d’importantes frictions entre des manières bien distinctes d’appréhender les rapports aux poissons, les frictions étant ici comprises comme des lieux fertiles à partir desquels de nouvelles dynamiques culturelles et de nouvelles structures de pouvoir voient le jour. La présente recherche ayant été effectuée en plein coeur de la pandémie associée au COVID-19, l’enquête ethnographique sur le terrain ne put être réalisée. Conséquemment, dans ce mémoire, je propose une analyse originale principalement fondée sur des données puisées dans un large corpus de littérature anthropologique et autochtone et sur des informations publiquement accessibles à distance via les réseaux sociaux et les cyberespaces. L’ensemble des données analysées appuient la proposition selon laquelle le contexte à l’étude serait au coeur d’importantes frictions entre deux régimes de valeur qui guident les rapports avec le poisson : d’abord, un régime de valeur traditionnel associé aux règles réciproques d’interaction, de prédation et de partage avec les chefs des peuples autres qu’humains qu’ils représentent et incarnent; ensuite, un régime de valeur marchande faisant sens dans une économie de marché capitaliste globalisée et globalisante. L’exemple de la résurgence de la First Salmon Ceremony, qui est présenté en conclusion, vient appuyer cette proposition. En effet, elle se présente comme un lieu d’affirmation, de négociation et de revendication politique, territoriale et identitaire important, et témoigne d’une continuité transformative caractéristique des cosmopolitiques autochtones contemporaines de la côte ouest. En plus de proposer de nouvelles pistes de recherche, ce mémoire constitue une invitation à repenser les logiques et les structures de pouvoir qui guident actuellement la gestion halieutique au sein des territoires autochtones du pays. / This research aims to better understand the frictions caused by the introduction of the salmon farming industry on the ancestral territories of the kwakwaka’wakw and nuu-chah-nulth nations of Vancouver Island. While this context has already been the subject of much research, the question of the relationship between humans and fish was generally put aside. In that sense, this thesis seeks to bridge this important gap. While the frictions are understood here as fertile places from which new arrangements of culture and power are born, I propose that the introduction of the salmon farming industry into the indigenous territories of Vancouver Island instigated significant frictions between different ways of understanding the relationships with fish. Because this research was conducted in the midst of the COVID-19 pandemic, an ethnographic field investigation could not be carried out. Consequently, in this thesis, I propose an original analysis mainly based on data drawn from a large corpus of anthropological and indigenous literature, but also on publicly accessible information from social networks and cyberspaces. All of the data analyzed support the proposition that the context under study is, in fact, instigating important frictions between two value regimes that guide relationships with fish: First, a traditional value regime associated with the reciprocal rules of interaction, predation and sharing with the chiefs of the other-than-human peoples they represent and embody; Then, a regime of market value making sense in a globalized and globalizing capitalist market economy. The example of the resurgence of the First Salmon Ceremony presented in the conclusion supports this proposition. In fact, it presents itself as an important space for political, territorial and identity claims, negotiation, and affirmation, while testifying the transformative continuity that characterize contemporary West Coast indigenous cosmopolitics. In addition to proposing new avenues of research, this paper is an invitation to rethink the logics and power structures that currently guide halieutic management within the indigenous territories of Canada.

Marine salmon farming is a new and fast-growing industry in Iceland after decades of uncertainties within aquaculture development in the country. While growing at a tremendous speed in the last few years, the development has been challenged by different social groups in regard to its socio-economic and environmental effects. Research has shown that there is a lack of knowledge on the perceptions on different stakeholders involved in the farming. This study aims to investigate how different stakeholders perceive the marine salmon farming industry being established in Bíldudalur, in the Westfjords of Iceland, by conducting a case study. Semi structured interviews were carried out with different stakeholders as well as an online survey was distributed to the residents of Bíldudalur, following a focus groupdiscussion. Analysis of the responses demonstrated that current aquaculture regulations have not held up with the expanding industry which has created tension amongst stakeholders. The results show that many worry about the wild salmon stock and that with current regulations, it is hard to predict how much marine farmed salmon will be bred in Iceland, due to weak regulations. Simultaneously, the local community of Bíldudalur has experienced a lot of positive changes in their rural community following the establishment of fish farming in their community. On this basis, further research is needed to compare the findings to other rural communities involved in fish farming in Iceland as well as further research on Iceland´s current changes in regulation and policies and how aquaculture development is promoted in Iceland.