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Paper analyzes the EU legal regulation of fishing. Specifically, it focuses on activities and norms, aiming to make european fisheries become sustainable and environmentally friendly. The paper summarizes the development of the common fisheries policy (CFP), which is one of the EU sectoral policies. Emphasis is placed on latest reform of CFP, which aimed among other things to sustainability. The next part deals with individual management tools, which is controlled amount of inputs and outputs to / from the fishing process. To restriction of outputs (amount of fishery products) is used setting total allowable catches and quotas. To restriction of inputs is used reduction of fishing capacity of vessels, which given to the assign rights and available resources is excessive, and also by reducing fishing effort. In addition to these tools are an inportant technical measures serving to reduce the impact of fishing on marine ecosystems, and in particular the prohibition or restriction of non-selective and destructive fishing techniques, or delimitation areas or periods in whitch fishing is prohibited. Paper in addition to fishing rules also focuses on control regulation. Control of compliance and penalties for non-compliance are regulated in the EU control system for fisheries. This is designed to ensure...

Recent shifts towards ecosystem based fisheries management (EBFM) around the world have necessitated consideration of effects of fishing on a larger range of species than previously. Non-selective multispecies fisheries are particularly problematic for EBFM, as they can contribute to erosion of ecosystem structure. The trade-off between catch of productive commercial species and abundance of low-productivity species is unavoidable in most multispecies fisheries. A first step in evaluation of this trade-off is estimation of productivity of different species but this is often hampered by poor data. This thesis develops techniques for estimating productivity for data-limited species and aims to help clarify EBFM policy objectives for the fisheries of New South Wales (NSW), Australia. It begins with development of an age-structured model parameterised in terms of optimal harvest rate, UMSY. UMSY is a measure of productivity, comparable among species and easily communicated to managers. It also represents a valid threshold for prevention of overfishing. The model is used to derive UMSY for 54 Atlantic fish stocks for which recruitment parameters had previously been estimated. In most cases, UMSY was strongly limited by the age at which fish were first caught. However, for some species, UMSY was more strongly constrained by life history attributes. The model was then applied to twelve species of Australian deepwater dogshark (Order Squaliformes), known to have been severely depleted by fishing. Results showed that the range of possible values of UMSY for these species is very low indeed. These findings enabled a preliminary stock assessment for three dogsharks (Centrophorus spp.) currently being considered for threatened species listing. Preliminary results suggest they have been overfished and that overfishing continues. Finally, an Ecopath with Ecosim ecosystem model, representing the 1976 NSW continental slope, is used to illustrate trade-offs in implementation of fishing policies under alternative policy objectives. Results are compared with those of a biogeochemical ecosystem model (Atlantis) of the same system, built by scientists from CSIRO. While there were large differences in model predictions for individual species, they gave similar results when ranking alternative fishing policies, suggesting that ecosystem models may be useful for exploring broad-scale strategic management options.

Recent shifts towards ecosystem based fisheries management (EBFM) around the world have necessitated consideration of effects of fishing on a larger range of species than previously. Non-selective multispecies fisheries are particularly problematic for EBFM, as they can contribute to erosion of ecosystem structure. The trade-off between catch of productive commercial species and abundance of low-productivity species is unavoidable in most multispecies fisheries. A first step in evaluation of this trade-off is estimation of productivity of different species but this is often hampered by poor data. This thesis develops techniques for estimating productivity for data-limited species and aims to help clarify EBFM policy objectives for the fisheries of New South Wales (NSW), Australia. It begins with development of an age-structured model parameterised in terms of optimal harvest rate, UMSY. UMSY is a measure of productivity, comparable among species and easily communicated to managers. It also represents a valid threshold for prevention of overfishing. The model is used to derive UMSY for 54 Atlantic fish stocks for which recruitment parameters had previously been estimated. In most cases, UMSY was strongly limited by the age at which fish were first caught. However, for some species, UMSY was more strongly constrained by life history attributes. The model was then applied to twelve species of Australian deepwater dogshark (Order Squaliformes), known to have been severely depleted by fishing. Results showed that the range of possible values of UMSY for these species is very low indeed. These findings enabled a preliminary stock assessment for three dogsharks (Centrophorus spp.) currently being considered for threatened species listing. Preliminary results suggest they have been overfished and that overfishing continues. Finally, an Ecopath with Ecosim ecosystem model, representing the 1976 NSW continental slope, is used to illustrate trade-offs in implementation of fishing policies under alternative policy objectives. Results are compared with those of a biogeochemical ecosystem model (Atlantis) of the same system, built by scientists from CSIRO. While there were large differences in model predictions for individual species, they gave similar results when ranking alternative fishing policies, suggesting that ecosystem models may be useful for exploring broad-scale strategic management options.

The noble crayfish (Astacus astacus) is critically endangered in Sweden. This is mainly due to the crayfish plague (Aphanomyces astaci), a lethal disease that, among other things, can be spread through the stocking of fish from contaminated water or contaminated fishing gear. The largest single propagation path is the illegal introduction of infected signal crayfish (Pacifastacus leniusculus). A conservation measure for crayfish is to re-introduce it to where it has a chance to survive, though a sustainable, locally regulated fishing can also serve as an indirect protection for the species. When the local inhabitants are allowed to keep their fishing culture and when fishing is acceptable, the incentive for illegal stocking of signal crayfish is low. However, it is important to avoid overfishing because the recovery, especially in the northern regions, can take several years. Therefore, it is important to know how crayfish respond long-term to fishing and environmental factors. Crayfish populations became extinct in the River Ljungan for unknown reasons in 1999. The water flow of the river has been used for activities such as fishing, timber transport and hydroelectric power since the 1500s, and the noble crayfish has been part of the fauna since the last century. The River Ljungan was known as one of Sweden's best fishing areas for crayfish and fishing became an important part of the local tradition. When the crayfish populations became extinct, a reintroduction program was a natural step, and crayfish are nowadays re-established in the river. From 1963 to 1990 the Swedish Board of Fisheries collected data from crayfish fishing in the River Ljungan to determine the economic damage to fishery owners caused by the construction of a power plant. After each season the fishermen reported the catch. In this thesis, the data was used to investigate which factors influence the long-term size of the crayfish catch and how the crayfish catches were affected by the power plant building. After re-introduction of the crayfish to the River Ljungan, the local fishermen monitored the population development in a simple, standardized way. To examine the validity of their measurements and to investigate the body growth of the individuals, a capture-recapture technique with a permanent marking of the crayfish was used. The crayfish catches were primarily impacted by the previous years' catch size, and a large catch the previous year resulted in a reduced catch the following year. A mild winter climate (NAO-index > -0.7) six years before the catch implied a large catch, whereas a high water flow during the autumn or spring (>95m3s-1) two years before the catch, implied a poor catch. Major habitat changes in the form of greatly reduced water flow (~90%) were negative for crayfish catches. The standardized method of fishing used by the local fishermen to monitor the development of the crayfish population was precise enough to detect population trends and this method can therefore be recommended to monitor future re-introductions of crayfish. Although the River Ljungan is located at the northern edge of the species' range, noble crayfish in the river presently have a body growth rate that is close to the maximum measured for crayfish (8 mm/moult for females and 10 mm/moult for males). Based on the results, the most important advice for sustainable fisheries in Ljungan and other northern rivers is to: Monitor the population trends, NAO-index and water flow in May and October.  Use the results from the monitoring to determine the number of allowed fishing days and traps. Collect data about the catch size and efforts from legal fishing and use it to evaluate the sustainability of the fishing. Enhance the buildup of the harvestable cohort by -saving reproductive females -introduce a size limit of 10 cm -provide proper shelters for the non-harvestable cohort. / Flodkräftan (Astacus astacus) är akut hotad i Sverige främst på grund av kräftpest (Aphanomyces astaci). Kräftpest är en dödlig sjukdom som bland annat kan spridas vid fiskutsättningar från smittade vatten eller med smittade fiskeredskap. Den enskilt största spridningsvägen är illegala introduktioner av smittade signalkräftor (Pacifastacus leniusculus). En bevarandeåtgärd för flodkräfta är att återintroducera den till lokaler där den har chans att överleva, men ett hållbart fiske med lokal styrning kan också fungera som ett indirekt skydd för arten. När lokalbefolkning tillåts att behålla sin fiskekultur och fisket är bra, blir incitamentet för illegal inplantering av signalkräfta lågt. Men det är viktigt att undvika överfiske då återhämtning, speciellt i nordlig miljö kan ta åtskilliga år. Därför är det betydelsefullt att veta hur flodkräftan svarar på fiske och omgivningsfaktorer i det långa loppet. Flodkräftbeståndet dog, av okänd anledning, ut i Ljungan 1999. I Ljungans flöde har det fiskats, flottats timmer och utvunnits vattenkraft etc. sedan 1600-talet och under det senaste århundradet har flodkräftan varit en del av Ljungans fauna. På sin tid var det en av Sveriges bästa lokaler för flodkräfta. Kräftfisket blev en viktig del av den lokala traditionen, så när kräftbeståndet dog ut var återintroduktion en självklarhet och flodkräftan har åter sin hemvist i älven. Under perioden 1963 till och med 1990 samlade Fiskeriverket in data från kräftfisket i Ljungan för att fastställa den ekonomiska skadan som fiskerättsägarna åsamkats i samband med ett kraftverksbygge. Efter varje säsong fick fiskarna rapportera hur fisket gått. I den här avhandlingen, har det materialet använts för att undersöka vilka faktorer som påverkar kräftfångstens storlek på lång sikt och hur kräftfångsterna påverkades av kraftverksutbyggnaden. Efter återintroduktionen av flodkräfta till Ljungan mättes beståndsutvecklingen på ett enkelt, men standardiserat sätt av de lokala fiskevårdsområdena. För att undersöka validiteten av deras mätningar och hur kräftornas individuella utveckling fortskred, användes fångst- och återfångstteknik, med permanent märkning av kräftorna. Kräftfångsternas storlek påverkades främst av tidigare års fångststorlek; en stor fångst föregående år innebar minskad fångst följande år. Ett milt vinterklimat (NAO-index > -0.7) sex år före fångst innebar bättre fångster, medan höga vattenflöden höst och vår (>95m3s-1) två år före fångsttillfället innebar sämre fångst. Större habitatförändringar i form av kraftigt reducerade vattenflöden (~90%) var negativt för kräftfångsterna. Den standardiserade metoden som fiskevårdsområdena använt för att mäta beståndsutvecklingen var tillräckligt precis för att påvisa populationsutvecklingen och kan därför rekommenderas också för uppföljning av andra återintroduktioner av flodkräfta. Trots att Ljungan ligger i norra kanten av flodkräftans utbredningsområde har flodkräftorna i Ljungan för närvarande en kroppstillväxt som är nära den maximala som uppmätts för flodkräfta (8 mm/ömsning för honor och 10 mm/ömsning för hannar). Utifrån resultaten är de viktigaste råden för ett hållbart fiske i Ljungan och andra nordliga vattendrag att: Övervaka kräftstammens utveckling, NAO-index samt vattenflöde i maj och oktober.  Använda resultaten från övervakningen för att bestämma antalet tillåtna fiskedagar och burar. Samla in data om fångststorlek och hur många burnätter som faktiskt gjordes under säsongen. Använda data för att utvärdera fiskets hållbarhet. Stärka uppbyggnaden av den fångstbara storleken genom att -spara reproduktiva honor -införa en storleksgräns på 10 cm -tillse att det finns gömslen för kräftor av icke-fångstbar storlek.

Recent shifts towards ecosystem based fisheries management (EBFM) around the world have necessitated consideration of effects of fishing on a larger range of species than previously. Non-selective multispecies fisheries are particularly problematic for EBFM, as they can contribute to erosion of ecosystem structure. The trade-off between catch of productive commercial species and abundance of low-productivity species is unavoidable in most multispecies fisheries. A first step in evaluation of this trade-off is estimation of productivity of different species but this is often hampered by poor data. This thesis develops techniques for estimating productivity for data-limited species and aims to help clarify EBFM policy objectives for the fisheries of New South Wales (NSW), Australia. It begins with development of an age-structured model parameterised in terms of optimal harvest rate, UMSY. UMSY is a measure of productivity, comparable among species and easily communicated to managers. It also represents a valid threshold for prevention of overfishing. The model is used to derive UMSY for 54 Atlantic fish stocks for which recruitment parameters had previously been estimated. In most cases, UMSY was strongly limited by the age at which fish were first caught. However, for some species, UMSY was more strongly constrained by life history attributes. The model was then applied to twelve species of Australian deepwater dogshark (Order Squaliformes), known to have been severely depleted by fishing. Results showed that the range of possible values of UMSY for these species is very low indeed. These findings enabled a preliminary stock assessment for three dogsharks (Centrophorus spp.) currently being considered for threatened species listing. Preliminary results suggest they have been overfished and that overfishing continues. Finally, an Ecopath with Ecosim ecosystem model, representing the 1976 NSW continental slope, is used to illustrate trade-offs in implementation of fishing policies under alternative policy objectives. Results are compared with those of a biogeochemical ecosystem model (Atlantis) of the same system, built by scientists from CSIRO. While there were large differences in model predictions for individual species, they gave similar results when ranking alternative fishing policies, suggesting that ecosystem models may be useful for exploring broad-scale strategic management options. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate

Ongoing urbanization and the demand for food, water and recreation influence the sustainability of blue urban spaces. Fishery is a prominent use of urban blue space and can cause pressure on urban nature, its water bodies and fish. This growing pressure requires more attention to how urban dwellers use and value this space and requests smart fishing management for urban areas. To improve knowledge on how to realise sustainable urban fishing, this thesis used an interview study in the city of Hamburg in Germany. Six fishers, two representatives of fishing clubs and one representative of the fishing club association, were interviewed, and the results were combined with observations during one and a half weeks of field study and literature review. The study shows that Germany uses a distinctive approach regarding fishing management with a general ban on catch-and-release and strict regulations. Since fishing law is a state law, the federal state of Hamburg is responsible for its fishing management. The main managing tool is the new fishing law from 2019, developed with scientists and stakeholders to improve fishing in an ethical and sustainable way. The stakeholder’s different impacts on and interests in the rivers of Hamburg have to be respected and are shown in this thesis. The study concludes that management practices have to be managed adaptive to consider changing environmental conditions. Generic fishing management practices (e.g., education of fishers) are limited, while most have to be individually adapted for the environment and fishing culture (e.g., fish protection).