Coastal aquaculture is among the fastest growing sectors of the food producing industry. Bivalve farming is a promising activity in low income countries were mollusk could be cultured under low technology and budget, contributing to reduce poverty and assuring food security. Site selection has been considered as a key process in successful aquaculture developments. A suitability model for mangrove oyster farming in the PiraquC-aqu/PiraquC-mirim estuarine system - PAPMES (Espirito Santo, Brazil) was developed. The suitability model is based on Multi-criteria Evaluation (MCE) which consists of selecting criteria, define their acceptable and optimum ranges, assign their weights of relative importance, and combine suitability criteria under a decision rule. A georeferenced database was created with 8 water quality variables considered related to the habitat requirements of mangrove oyster, with 19 field sampling campaigns on 6 samplings sites embracing an area of 51 lha. Low salinity and dissolved oxygen levels were detected in the upper estuarine sections. Using the geographic information system (GIs) Idrisi32, point data were converted to continuous surface models using secondorder polynomial fit. The normalization process aimed at standardizing the set criteria considering a single scale ranging from low (i.e., 0) to high suitability (i.e., 255). Through pairwise comparison technique weights were assigned to each criteria. Salinity and dissolved oxygen were considered the most important criteria because of their relationship to oyster short-term survival. A weighted linear combination and two constraints (i.e., fecal coliform > 43 MPN1100mL and navigation channel) were applied as the MCE decision rule. An area of 75ha (14.6% of the PAPMES) was considered constrained for mangrove oyster fanning. Two suitability models were performed using average and low salinity values. Suitability maps developed onto the 0 - 255 range were reclassified in 4 categories: unsuitable, moderately suitable, suitable, and very suitable. In both models, no area was indicated as unsuitable. Although the low salinity model could be considered more restrictive, it yielded a very suitable area 26% larger than the average salinity model. The combination of the two models could bring together risk taking and risk-averse perspectives, respectively. The output of such combination is a map locating 80ha of very suitable areas for mangrove oyster farming, with 9.5ha preferentially designated for intertidal farming using racks. Aquaculture zones are discussed in terms of their interactions with other systems at higher spatial scales, such as the watershed and the coastal zone. GIs can serve as an integrative environment to integrate complex variables in multiple scales. It is only through its integration in multisectoral development plans and programs for the watershed and coastal zone realms that coastal aquaculture will be recognized as sustainable enterprise.

Social interactions and aggression among salmonid fish are known to induce stress responses, particularly in subordinate fish, and the physiological effects of these stress responses have implications for fish in both aquaculture and natural environments. The physiological responses exhibited by subordinate fish (i.e. those fish that are low ranking in a social hierarchy) vary depending on the nature and extent of the social interaction and can also be influenced by environmental factors. Artificial environments - typically aquaria - generally elicit a larger stress response in the subordinate fish due to the fish being held in close confinement. The present study has clearly demonstrated that the physiological responses to social interaction and the formation of dominance hierarchies in rainbow trout and brown trough are affected by the environment of the fish e.g. whether the environment is artificial or natural, and stable or subject to fluctuations. In an artificial environment, the present study has confirmed that the effects of the social stress encountered by subordinate fish include decreases in growth rate and condition and increases in plasma cortisol but has also demonstrated decreases in the ability to secrete further cortisol and increases in the standard metabolic rate of subordinates. In a semi-natural environment these physiological consequences of subordinance were seen to be reduced; indeed with the presence of environmental perturbations no physiological differences were noted between dominant and subordinate fish. Finally the present study also investigated the role of cortisol in chloride cell proliferation and the determination of social status and concluded that cortisol appears to play a mineralocorticoid role in the proliferation of chloride cells and may also influence the outcome of social interactions.

The Saudi Arabian government has announced an economic development plan (Vision 2030) to invest in a range of industries across the Kingdom, one of which is the development of aquaculture. In the face of a likely increase in Red Sea fish farming, we investigated the impacts of offshore fish farms on the coastal water quality of the Red Sea by a) measuring the environmental impacts of an operational Red Sea fish farm, and b) testing whether an existing aquaculture modeling software can be used as a meaningful planning tool in the development of Red Sea aquaculture. Water quality parameters such as dissolved oxygen, nutrients, particulate matter, chlorophyll, ammonium, and bacterial abundance were measured seasonally over the course of a year around an offshore fish farm along the south-central coast of Saudi Arabia to determine the impacts of fish farm effluent on the surrounding waters. Bacteria, phosphate, inorganic nitrogen, and suspended particulate matter showed patterns of enrichment close to the fish farm. Additionally, dissolved oxygen has slightly lower concentrations close to and down current from the fish farms. Benthic sediments from a nearby coral reef were also assessed for organic enrichment, but concentrations of total organic carbon and total nitrogen were not significantly different from those at an offshore reef. The data from these sampling efforts were then used as input parameters for an aquaculture modeling software (AquaModel.net), however many of the input parameters required to run the model were unavailable and meaningful conclusions could not be drawn from the results. Through field studies and modeling, we assessed the current impact of a Red Sea fish farm on water quality with the goal of predicting the potential impacts of future offshore aquaculture development in Saudi Arabia.

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The ecology and behavior of nine species of anemonefishes and ten species of sea anemones were studied at a variety of sites in the region of Madang, Papua New Guinea. More than 95% of the suitable anemones in the region were occupied by anemonefishes. Each species of fish had a distinct pattern of host specificity and population surveys at three replicate reef sites within four locations situated at varying distances from the mainland (nearshore, mid-lagoon, outer barrier, and offshore), indicated that each species of host anemone and anemonefish lived within a particular range of locations. Recruitment was monitored to anemones in natural populations and to anemones that had their resident fishes removed. Significantly more fish recruited to anemones without residents. Each fish species recruited into the host species and locations occupied by their adults. Thus, recruitment had a strong effect on patterns of anemonefish host specificity and distribution, but fish abundance was limited by the availability of anemones. / The host location and association behaviors of laboratory raised anemonefishes were examined. Juvenile anemonefishes that were competent to settle were released in the field at different distances and orientations away from anemones. The fishes were only attracted toward particular species of anemones, and they used chemical cues released from anemones and rheotaxis to locate their hosts. Resident fishes were aggressive toward new recruits and usually prevented them from staying with anemones. Recruiting anemonefishes contacted the tentacles of most anemone species without harm, but in some cases the fishes were stung. Forced contact tests with anemonefish eggs, larvae, juveniles, and adults showed that the fish species tested developed some level of protection from anemones during metamorphosis from a pelagic larva to a benthic juvenile. Forced contact tests with fishes reared in complete isolation from anemones demonstrated that the protection was innate for some species of anemonefishes. However, juvenile fishes still went through acclimation behavior during the initial interaction with an anemone, even if the fishes were innately protected. Immunological studies with polyclonal antibodies to anemone mucus antigens showed that anemonefishes acquire anemone antigens in their mucus coat during their association with anemones. / Source: Dissertation Abstracts International, Volume: 53-11, Section: B, page: 5524. / Major Professor: R. N. Mariscal. / Thesis (Ph.D.)--The Florida State University, 1992.

The study establishes the value in recreational use of Florida's saltwater tourist fishery, using exact Hicksian compensating and equivalent variation methods. The Hicksian approach removes the approximating error of Marshall's consumer's surplus measures. The theoretical model underlying the angling experience emphasizes the multi-purpose nature of the tourist trip. It is based upon a Gibbs-type approach in which variable on-site cost proxies market price and travel cost enters the budget constraint. On-site cost and angling success rate are explicitly incorporated into a system of behavioral relations. Some restrictive assumptions found in similar studies are relaxed with composite goods utility. Empirical estimates for aggregated and subgroup angling categories are made with multiple equation models of identified linear and non-linear specifications. There is some evidence that shore anglers might be more and less sensitive to changes in on-site cost and success rate, respectively. Single equation models are also used, but exhibit downward coefficient bias. Results corroborate the findings of previous studies that the market and non-market values of Florida's marine recreational fishery are very large relative to state product and/or commercial sector activity. Inelastic short run price and success rate elasticity is confirmed. Hicksian methods are not shown to be significantly more accurate than most Marshallian ones, except in the case of the direct aggregate user opinion method. Sensitivity analysis offers policy implications supporting a marine tourist fishing license and stock rebuilding schemes, such as bag limits for depleted species. The unrecoverable deadweight burden to society caused by a $10 annual tourist fishing license is less than one percent of the $31 million in direct, adjusted license revenues estimated to be forthcoming annually. / Source: Dissertation Abstracts International, Volume: 45-09, Section: A, page: 2917. / Thesis (Ph.D.)--The Florida State University, 1984.

Invasive colonial tunicates pose substantial economic threat to the shellfish aquaculture industry, but their population dynamics and ecological impacts are highly variable and region-specific. This thesis contributes to our regional understanding of two such tunicates in Oregon. The first chapter explores the population dynamics of Didemnum vexillum, one of Oregon’s top 100 most dangerous invasive species, at an oyster farm. From May 2011 to 2016 the population fluctuated extensively, though did not exhibit any net growth over the study period. In the second chapter, I demonstrate that Botrylloides violaceus had no impact on the growth, condition, or organic composition of oysters and mussels grown in a simulation of longline aquaculture. Together, these studies paint a cautiously positive outlook for the shellfish aquaculture industry in Oregon. This thesis includes previously unpublished co-authored material.

Meagre and the greater amberjack are promising emerging species in aquaculture. This is due to their fast growth rate, large size, high processing yield and high quality fillet. However, little is known about the immune system of these fish and several potential pathogenic threats to sustainable culture of these fish have been identified. Therefore, this thesis has begun to characterise the immune response of these species in order to better combat pathogenic threats. The focus of this thesis is the identification, modulation and monitoring of key innate and adaptive immune genes. This is achieved by identifying conserved regions of target gene sequence and designing consensus primers to these in order to generate a partial sequence, which could then be used as a base from which RACE PCR could be performed to obtain full sequence. The identified sequence was then used to produce qPCR primers, anti-meagre IgM and anti-meagre IgT monoclonal antibodies and a functional synthetic greater amberjack piscidin active peptide. Using the developed qPCR primers the constitutive expression of target genes was determined in the gills, gut, head kidney and spleen. Changes in transcript expression were then monitored in these tissues in response to PAMP stimulation in vivo and in vitro in order to better understand how these genes are modulated by viral, bacterial and fungal stimuli. Furthermore, the meagre development of the immune system was monitored from 1 day post hatch (dph) until 120 dph, providing insights into when immune maturity is achieved. Monoclonal antibodies were also produced and their viability tested in a variety of assays including Western blot, Immunohistochemistry and ELISA. Finally, A synthetic greater amberjack piscidin was produced and the bacteriostatic capabilities of this peptide were tested and showed promising results against known bacterial fish pathogens, indicating a potential for future uses within and outwith aquaculture.

Among efforts to develop sustainable approaches towards the intensive rearing of finfish within open marine waters, is the development of integrated aquaculture techniques. Integrated Multi-Trophic Aquaculture (IMTA), has been promoted as a way to reduce unwanted environmental impacts associated with the intensive production of marine finfish within net-pens. The principle aim of this concept, is the bioremediation of nutrient discharges from fish aquaculture. This is to be achieved by integrating fish cultivation with the growing of species from lower trophic levels, which use the nutrient discharges as a food source. Many studies have been performed that investigate the ability of various species of macroalgae to remove dissolved nutrient discharges, and the ability bivalves to remove solid-bound nutrients, presented as either fish faeces, or an enhanced production of phytoplankton that may be promoted by nutrients emitted by fish-farms. IMTA has also been suggested as a means to improve overall productivity per unit of feed applied to fish, through the conversion of nutrient emissions into additional biomass, such as the tissues of macroalgae or bivalves. Within the research community which focuses upon the environmental impacts of aquaculture, there is a growing awareness that sustainable solutions to aquaculture production cannot be realised through a focus restricted to the growing-phase, and to a limited set of environmental impacts which may this activity may produce. This is because changes to a specific production phase often promote changes at phases located elsewhere along a products value chain. Life-Cycle Assessment (LCA), is a method employed for modelling the environmental impacts that may potentially be generated across the value chain of a product. It is particularly useful for identifying instances of environmental impact shifting; a term used to describe situations where efforts to reduce the contribution of a specific production phase towards one or more environmental impacts, has the effect of either displacing this contribution to another phase, or increases the contribution of production towards different environmental impacts. Despite its apparent suitability, LCA has not previously been fully applied to the environmental impact modelling of open-water IMTA systems. The work presented in the following thesis advances this research front, by using LCA to explore the potential for environmental problem shifting occurring as a consequence of replacing intensive monoculture production, with IMTA. Comprehensive datasets have been acquired from the Chilean aquaculture industry, describing the production of aquafeed and Salmo salar, as well as for the production of the Phaeophytic macroalga, Macrocystis pyrifera, and the molluscan bivalve, Mytilus chilensis. Using LCA methodology, the production of salmon feed, and the production of S.salar, M.pyrifera and M.chilensis, have been assessed for their capacity to contribute towards a variety of global-scale, environmental impacts. IMTA consisting of either S.salar and M.pyrifera, S.salar and M.chilensis, or all three of these species, and combined at ratios required for a bioremediation efficiency of 100 %, 50%, or 20 % of either nitrogen or phosphorous emission from fish, is compared to the monoculture production of S.salar. The comparison is based upon a standardised functional unit, with each species produced through IMTA, being modelled as part of the reference flow required to fulfil the functional unit. Monoculture is compared to IMTA upon the basis of nutritional function, by using a functional unit of mass-adjusted protein content, and mass-adjusted economic value. The use of economic value is based upon the ‘best-case’ assumption, that it serves as a proxy for the total nutritional function that each product offers to human society. The LCAs presented in this study have produced a number of results. Salmon ingredients derived from agricultural crops and animals account for the majority (between 71 % to 98 %) of contributions towards the impacts of compound salmon feed. In general, agricultural crops ingredients contribute more to these impacts than do agricultural animal ingredients, and account for between 31 % and 87 % of the contributions from all ingredients and inputs. In contrast, the combined supply of fish meal and fish oil from capture fisheries is responsible for between 0.13 % and 11 % of all impacts. Vegetable oil accounts for the vast majority of contributions from ingredients derived from agricultural crops. Vegetable oil is modelled as a 50 : 50 blend of sunflower oil and rapeseed, oil, but sunflower oil accounts not only for most of the contributions from vegetable oil, it is responsible for over 50 % of the contributions that all agricultural crop based ingredients contributes towards some impact categories. Replacing sunflower oil with rapeseed oil reduces the contributions of salmon feed by between 6 % and 24 % across 10 out of the 11 impact categories. When compared upon the basis of equal weight, the contributions of fish oil are between 18 % and 99 % lower than those from rapeseed oil. The production of feed is responsible for the majority of contributions (between 32 % and 86 % ) to all impacts of salmon grow-out production. The production of salmon-smolts accounts for between 3 % and 18 %. The majority (64 %) of contributions towards the eutrophication potential of salmon production are from nutrient emissions, which are the result of fish metabolism, whilst nutrients released through the production of feed, the majority of these being from the agricultural production of crop and animals, account for 32 %. Feed production is also a major contributor to the impacts of land-based smolt production, but these contributions (between 12 % and 37 % across all impact categories) are of a lower magnitude than those from the supply of feed to the grow-out phase. Inputs of salt, and inputs of both electricity produced in a diesel power generator and obtained from the national electricity network, are also notable contributors (between 5 % and 67 %, 4 % and 29 %, and 2 % 47 %, respectively) towards the impacts of smolt-production. The main contributors towards the potential impacts of kelp grow-out production (excluding eutrophication potential) are the supply of infrastructure (between 14 % and 89 %), operation of a diesel-powered motorboat for maintenance purposes (between 1 % and 89 %), and the supply ‘of seeded cartridges’ (between 9 and 49 %). The major contributors from the production of ‘seeded cartriges’ in a land-based facility are the supply of electricity from the national electricity network, the supply of fresh water, and the treatment of waste water. The impact potentials of producing seed in this facility might be reduced if the scale of operation is increased. Removal of nitrogen and phosphorous upon the harvesting of kelp is calculated based upon kelp tissue contents of these nutrients. The harvesting of 200 tonnes ha / yr-1, results in a eutrophic potential with a negative value (-376.51 kg of phosphate equivalents). The removal of such a quantity of nutrients might be beneficial if the local marine environment is at risk of hypernutrification, but when no such problem is present, the potential for undesirable consequences of nutrient sequestration should be considered. The major contributor towards the impacts of mussels is the provision of infrastructure (between 25 % and 99.5 %, excluding eutrophication potential). Infrastructure is also responsible for the majority of contributions from mussel seed production. The provision of cotton mesh bags, which are used to aid attatchment of seed to drop-ropes in the grow-out phase, account for between 37% and 99 % of the contributions from the infrastructure from the grow-out phase. This result suggest that either the impacts of mussel production can be reduced by using an alternative material with lower environmental impact potentials, or the inventory data describing the producing of cottonmesh bags requires some improvement. The outcomes of the LCAs of the different IMTA scenarios, are interesting. The results show that choice of species, and the ratios of their combination as required for the different efficiencies of bioremediation, can have a significant effect upon the comparison between IMTA and monoculture. / The study demonstrates a potential for environmental problem shifting as being a consequence of IMTA, especially when the functional unit is mass-adjusted economic value. As bioremediation efficiency increases, contributions towards eutrophication decrease. However, this reduction is achieved at the cost of increasing the contributions of IMTA towards those impact categories, such as ‘ozone layer depletion,’ for which it has a greater contribution than does monoculture. In general, it cannot be concluded from these results that open-water IMTA represents a more sustainable alternative to the monoculture production of Atlantic salmon. The sustainability of IMTA is shown to be dependent upon a variety of trade-offs, between individual environmental impacts, and between these impacts and the nutritional function that the system is capable of providing.

No description available.