Recent legislative changes have increased the need to monitor contamination effects in Scottish waters and have consequently elevated demand for research into vertebrate and invertebrate ecotoxicological techniques. Selected invertebrate ecotoxicological techniques were used to measure the effects of two industrial contaminants found in Scottish sea lochs i) the synthetic pyrethroid cypermethrin, licensed for treatment of lice infestations in the Scottish salmon farming industry and ii) polycyclic aromatic hydrocarbons (PAHs) released into Loch Leven via the Kinlochleven aluminium smelter. Mytilus edulis accumulated cypermethrin during exposure and exhibited shell closure behaviour. Neither neutral red retention (NRR) time of lysosomes nor aerial survival were affected by concentrations £1000 mg/l. As the shell closure effect occurred at concentrations greater than typical field concentrations (i.e. within and around almost sea cages), Mytilus does not demonstrate suitability for use as a study species when monitoring the biological effects of cypermethrin exposure. Carcimus maenas exhibited 50% mortality after 96 hours of exposure to the salmon treatment dose of 5 mg cypermethrin/1. Exposed crabs exhibited a tetanus-like behaviour. Sensitivity to cypermethrin was comparatively greater inCarcinus than in Mytilus . Activity of the detoxification enzyme glutathione S-transferase (GST) was assessed as a potential biomaker of exposure. GST activity was induced in crabs after 7 days of daily exposure to cypermethrin concentrations of 50 mg/l and 500 ng/l. Although GST activity was sensitive to cypertherin exposure, the brevity of the GST response reduces scope for its use as a biomarker for cypermethrin exposure in the field. Some of the techniques investigated here offer potential for further development and possible implementation into monitoring strategies for the Scottish coastal environment.

No description available.

by Wong Wai-Yee, Dolly. / Bibliography: leaves 90-102 / Thesis (M.Phil.) -- Chinese University of Hong Kong, 1983

The thesis took an interdisciplinary, problem-oriented approach to address the research problem: ’Is farmed fish capable of replacing wild-caught fish in the Malaysian diet?’ The main objectives of the project were to assess current fish consumption habits, evaluate the impacts of these on sustainability of fish stocks and determine whether aquacultured products could be a suitable substitution. A combination of data collection methods was used, namely dietary assessments, systematic literature review, market research interviews and surveys and analysis of electronic and paper-based official records. The review of the Malaysian food balance sheets showed a significant transition in diet over the last three decades, specifically with respect to an increase in animal protein by approximately 60% over this time, with fish as the major source of protein. To further explore the contribution of fish to the diet of Malaysians, and any ethnic and geographical differences in consumption, a food frequency questionnaire (FFQ) was developed to assess habitual dietary intakes within selected coastal, rural and urban populations across different cultural groups in Klang Valley. The FFQ provided a clearer picture of the quantities of fish consumed by Malaysians and enabled the characterisation of Malaysian fish consumers based on the types of fish species consumed for sustainability assessment purpose. The nutritional contribution of wild versus farmed fish was compared and contrasted. Results from this study, combined with detailed studies of perception of wild versus farmed fish by consumers, aquaculturists and wholesalers, provided a greater understanding of the factors that influence consumers’ fish buying and consumption habits. The key findings are discussed with respect to the sustainability of the current situation, potential for expanding the aquaculture sector to replace wild fish in the Malaysian diet and recommendations for future research and issues for policy makers involved in the expansion of the industry.

No description available.

No description available.

Recent studies have demonstrated that the morphologically similar white marlin (Kajikia albida) and roundscale spearfish (Tetrapturus georgii) co-occur in the western North Atlantic, including the U.S. Mid‐Atlantic Bight. Differences in scale morphology have been proposed as one morphological character to discriminate these species, but a thorough analysis of scale morphology is lacking. Because the validity of the roundscale spearfish was not established until 2006, much of the biological information previously collected for “white marlin” may include data for both white marlin and roundscale spearfish. The objectives of this study were to obtain a better understanding of the movements and habitat utilization of positively identified white marlin that inhabit the U.S. Mid-­‐Atlantic Bight during summer months, and to describe the morphological variation of white marlin and roundscale spearfish scales. Eleven long‐term (6 or 12 month) pop-up satellite archival tags were placed on white marlin that were caught and released in the U.S. recreational fishery. Nine tags reported information on temperature, pressure (depth), and light levels for light‐based geolocation for periods of 8 days to 12 months. Most fish moved out of the Mid-Atlantic Bight in September, and overwintered in areas ranging from east of the Gulf Stream off the Carolinas to the Caribbean, and as far south as northern Brazil. of the seven fish that retained tags for more than 40 days, five spent time in known spawning grounds in waters of the Dominican Republic leading up to the spring spawning season. These data demonstrate a large degree of connectivity among white marlin in the western North Atlantic. as noted in previous studies, individuals spent a large proportion of their time in the surface waters (0-10m; 75% across all white marlin pooled), the vast majority of their time in the top 100 m of the water column (97%), and within eight degrees of sea surface temperature (98%), although definite shifts in habitat utilization were evident as fish departed coastal offshore waters of the Mid‐Atlantic Bight. Diel habitat utilization varied greatly, with white marlin spending 81% of total nighttime in the surface waters (0‐10m), and only 26% of total daytime in surface waters. Past studies have characterized the scales of white marlin and roundscale spearfish as being morphologically distinct, but little effort has been made to describe variation within an individual, among individuals, or between species. to better understand morphological variation of scales and squamation patterns of distinct body regions of these two species, individual scales were collected from 11 specific anatomical regions, and scale patches were collected from 3 specific regions of each white marlin and roundscale spearfish brought into marlin tournament weigh stations in the Mid-Atlantic Bight during 2012 and 2013. Scales were measured and described, and scale patches were cleared and stained to examine the level of imbrication of the scales, as well as the overall squamation patterns. In addition to the scales, denticular plates, ossified formations occurring on the surface layer of the dermis, were measured and described. Although considable morphological variation was observed among scales from different anatomical regions of individuals of both species, white marlin scales generally have pointed anterior ends, fewer posterior points, and are more heavily imbricated than those of roundscale spearfish, which are frequently rounded anteriorly, but often have many posterior points and are farther separated within the skin. Over all areas and individuals, roundscale spearfish scales were significantly wider and had a lower length-­‐to-­‐width aspect ratio than those of white marlin. Detailed scale descriptions allow for a more accurate characterization of the variation within and differences between these two species, and could potentially be a valuable tool for investigating istiophorid systematics.

No description available.

Management of organic waste is a major problem for the New Zealand Mussel Industry. Currently most waste is discarded, and this represents a potential loss of both resources and revenue, unless an alternative use for this waste could be developed. Waste types were first identified, then quantified, first seasonally, then annually, to provide an estimate of total industry-wide waste production. Possible uses for this waste were then identified. Little investigative research has been undertaken on identifying alternative uses for mussel industry organic waste. The uses of organic waste as organic fertilizers, and the economic benefit of adding treated waste products to cement mix to improve its compressive strength and thermal insulation, are two primary objectives of this dissertation. The possibility of using mussel shell in agricultural liming as a substitute is also explored. The potential value of pre-grade waste as an organic fertilizer was explored by addition of decomposed tissue to tomato seedlings and by monitoring plant development and condition. Growth of treatment and control seedlings was monitored by counting the number of branches, stem heights, leaf numbers and total biomass. Analyses prove Perna canaliculus pre-grade organic waste has the potential to be exploited as an expensive, effective organic fertilizer, whereas Mytilus galloprovincialis pre-grade organic waste may not. Moreover, there is further potential to develop P. canaliculus pre-grade organic waste into an odourless, chemically stable fertilizer product. The potential value of post-grade waste in cement mixes to improve compressive strength was explored by addition of shell aggregate to cement mix. Analyses indicate that, as an aggregate, mussel shell has little to no structural potential, but does have latent thermal insulating properties. Recommendations are made to: - Separate Perna and Mytilus pre-grade waste products. - Further explore the thermal insulating potential of mussel-shell concrete. - Further explore techniques for treatment of Perna pre-grade waste as a fertilizer. - Further explore the use of crushed mussel shell as a potential limestone or sand substitute for agricultural, construction and engineering purposes. - Explore markets for Mytilus potential export, to reduce pre-grade waste production and problems of resettlement.

Doctor of Philosophy (PhD) / The management of fisheries has progressed over the past century in an attempt to solve the problem of open access. A range of controls, both economic and non-economic in nature, have been used to ration the use of marine resources. Unfortunately, many controls have failed to correct open access problems. Whilst a recent development in fishery control, protected areas defined as an area with a fishery free of extractive pressure, have been put forward as an arrangement which may, in conjunction with other controls, be used to overcome the over-exploitation of marine resources. Marine protected areas have been advocated in areas where other forms of fishery management are impractical or unsuccessful (Sumaila 1998). Arguments for protected area use are based around the heterogeneous nature of fisheries, uncertainties in marine populations and as a hedge strategy to reduce risks of over-exploitation (Conrad 1999a). Through the protection of biodiversity, improving the resilience of the ecosystem, protected areas may mitigate the effects of negative shocks (Ludwig et al. 1993 and Bostford et al. 1997). Further, protected areas have been suggested as a means to manage uncertainty and environmental stochasticity (Grafton and Kompas 2005 and Grafton et al. 2005). The protection of biomass and habitat has the potential to improve fishery returns even when stocks are not overly exploited, with the benefits accruing even from small-sized protected areas (Grafton et al. 2005). The use of marine protected areas as a management tool has resulted from a recognition that it is important to preserve biological habitats as well as stocks. From a societal point of view, the use of protected areas should be evaluated in the context of changes in resource rent and improvements in welfare. As fishery resources are often owned by a common group, usually society, management objectives should be to maximise the return from use of the resources, whether for extractive or non-extractive purposes. Given this decision criterion, protected areas can be evaluated in the sense of opportunity costs and benefits. Protected areas will influence the return from fishery resources through changes in access to fishing grounds, and thus harvest, effort and resource rent. Once a protected area is established, the flow of biomass from the protected area to the remaining fishing ground, may increase biomass, influence the effects of uncertainty and stochasticity, thus effecting mean harvests, effort and resource rent may increase. Changes in resource rent are dependent on other controls. Protected areas are a ‘blunt’ policy instrument, in the sense that they are not an instrument to capture resource rent or change the incentives of fishers. Models of marine protected areas in fisheries vary in complexity, however, a few key elements are necessary in analysing the effects of protected area creation. First, multi-species interactions have the potential to be significant in determining the outcome from a protected area; second, effort expended in the fishery must be dynamic, that is, it must be endogenously determined by the model as fishers will respond to changes in rent brought about through the establishment of a protected area; third, institutional structures that govern the expenditure of effort within a fishery will play an important role in the effectiveness of protected areas in increasing the resource rent of a fishery; and fourth, environmental stochasticity and uncertainty need to be included in the analysis. A stochastic and deterministic model of a predator-prey meta-population fishery was developed to analyse the effects of protected area creation within a fishery. Such a model has not previously been used to analyse protected area creation. The model was analytically solved to find the optimal biomass of each species in an individual patch. This allowed for a comparison of protected areas under a range of management controls ranging from those which led to open access fishing to those which led to an optimal steady-state biomass. The model allowed for linkages between sub-populations based on differing density related flows. Further, due to the linkages between species on both environmental and economic grounds, the effect of protected areas on different groups which target different species could be analysed. The benefits from protected area creation were classified into unique and non-unique benefits. Unique benefits were defined as those which solely flow from the use of a protected area as a tool in fisheries management. Two unique benefits were defined: • Improvements in the resilience of the fishery; and • Reductions in environmental stochasticity. The ability of a protected area to both improve the resilience of the fishery, and smooth fluctuations in environmental stochasticity have been shown to lead to increases in mean resource rent. Thus, protected areas were shown to form part of an optimal fisheries management structure. Generally, the resilience benefits were maximised for small-sized protected areas, whereas the reduced environmental stochasticity benefits were maximised for larger protected areas. The dispersal system between the protected area and the fishing ground affected the unique benefits from protected area creation. Sink-source dispersal increased the unique benefits from protected area creation, as stock movements occurred independently of relative population densities. The independent flow improved the ability of the protected area to hasten the return of the fishery to a steady-state and lessened the variation of harvests in the open fishing grounds. However, in the case where the protected area led to large differences in population densities, and if the area formed a sub-population that was linked to the surrounding fishing ground by density-dependent dispersal, the unique benefits are likely to be greater than under sink-source dispersal. The non-unique benefits were defined as those which could be obtained from other control mechanisms. These benefits were non-unique as they could be achieved from more stringent controls on fisher behaviour. The determinants of the non-unique benefit in terms of dispersal were the same as for the unique benefits. However, the economic conditions of the fishery determined the magnitude of the non-unique benefits. For fisheries with sub-optimal biomass, the unique benefits were greater than those with optimal steady-state biomass. The non-unique benefits identified from protected area creation were: • Changes in biomass towards optimal levels; • Changes in species biomass ratios towards optimal levels; and • Changes in effort towards optimal levels. Protected areas in fisheries may be an optimal policy choice to achieve the non-unique benefits of protected area creation. Protected areas, it has been argued, are a relatively low cost management tool, due to the lower monitoring and enforcement costs. Thus, the use of protected areas offer a solution to the problems of over extraction of fishery resources for lower transaction costs, which may erode the non-unique benefits under different policy instruments. If this is the case, then a protected area larger than is required to maximise the unique benefits of protected area creation could form part of an optimal fisheries management strategy. Whether the protected area is larger or smaller than the size that maximises both the unique and non-unique benefits of protected area creation would depend on the level of transaction costs involved in using alternative policy instruments. Protected areas were found to have distributional effects on the fishery due to changes in the species biomass ratio towards the predator species post protected area creation. The creation of a protected area will have distributional effects on the fishing industry if different fisheries target the different species separately. Fishers targeting predator species are likely to gain from the establishment of a protected area, as now the aggregate level of stocks of this species is greater, leading to both greater unique and non-unique benefits. For fisheries that target prey species, the benefits of protected area creation are lessened. The increased predation within protected area boundaries limited the unique benefits of the protected area. The low cost nature of a protected area will influence the portion of the fishery used for this type of control given an optimal policy programme. If protected areas are relatively low cost in comparison with other controls they should be used relatively more intensely. Further, the use of protected areas may hasten the evolution of fisheries away from open access exploitation towards controls which maximise the value of the fishery. With lower transaction costs, the ability to adopt protected areas over other forms of management is greater, and by doing so, the movement towards optimal exploitation will improve the discounted value of the fishery. The analysis presented in this thesis examined the benefits of protected areas to fisheries. The focus of the study was placed on the benefits to flow to a fishery if a protected area was used as a tool for wild-harvest fisheries management. Marine protected areas also have the potential to generate a range of other benefits, such as recreational values, non-use values, and potential improvements in consumer surplus from fish caught within fisheries that use protected areas. These other benefits would need to be considered when determining whether or not a protected area should be created in a fishery.