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1
Ward, Christine. „One fish, two fish, red fish, blue fish, a journey into the oceans“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ39708.pdf.
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2
He, Ping. „Antioxidants in fish meals, fish feeds and farmed fish“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ39660.pdf.
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3
Cho, Chʻang-in Choi Nan-young. „Dad fish /“. Monterey, Calif. : Monterey Institute of International Studies, 2004. http://library.miis.edu/thesis/TI04%5F5.pdf.
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4
LaMacchia, Brian A. (Brian Andrew). „Internet fish“. Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/11049.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (leaves 98-102).
by Brian A. LaMacchia.
Ph.D.
5
Taglieber, Joe. „Everything Fish“. abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1453613.
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6
Rogers, Douglas E. „Self fish /“. Online version of thesis, 2010. http://hdl.handle.net/1850/11675.
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7
Speller, Camilla F. „One fish, two fish, old fish, new fish: investigating differential distribution of salmon resources in the Pacific Northwest through ancient DNA analysis /“. Burnaby B.C. : Simon Fraser University, 2005. http://ir.lib.sfu.ca/handle/1892/2023.
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8
Houwelingen, Adriana Cornelia van. „Fish against thrombosis? dietary fish and cardiovascular risk profile /“. Maastricht : Maastricht : Rijksuniversiteit Limburg ; University Library, Maastricht University [Host], 1988. http://arno.unimaas.nl/show.cgi?fid=5411.
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9
Griffith, Elias, und Jacob Iljans. „Secure Fish Feeder : Automatic secure fish feeder to make sure you do not overfeed your fish“. Thesis, KTH, Mekatronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-296333.
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This project aims to provide fish keepers with a safe and simple way to feed their pets while abroad or in any other situation where they do not have the ability to feed their fish by hand. Overfeeding is an unfortunate albeit common reason for mass death in an otherwise safe and healthy aquarium. While overfeeding to land dwelling pets might have negative health implications, the rapid damage seen in an aquarium is unparalleled in other environments. This is due to the release of ammonia that occurs when excess food (and partially fecal matter) is decomposed. Moderate feedings provide adequate nutrition for the pets, while keeping ammonia production at a level where it can be converted to nitrite and lastly the rather harmless compound nitrate. Most, if not all, feeders on the market today base their feedings solely off of volume, but this can lead to large variations in feeding size, due to variations in air between pellets in the feeding portions. By adding a failsafe with weight, we can fully prevent any chance of overfeeding, and thus ensuring a long and healthy life for our pets. Overall the goals of a safe fish feeder were accomplished, although the weighing was not as accurate as it optimally would have been.Med det här projektet syftar vi på att tillförse akvarieägare med ett tryggt och enkelt sätt att mata sina fiskar när de är utomlands eller av annan anledning inte har möjlighet att mata för hand. Övermatning är en olycklig men dessvärre vanlig anledning till massdöd i ett annars hälsosamt akvarium. Även om övermatning hos landdjur kan ha ohälsosamma konsekvenser, så är det aldrig lika skadligt på kort sikt som det är i ett akvarium. Det här beror på att överbliven mat (och även till viss del avföring) i en vattenmiljö snabbt omvandlas till ammoniak under förmultning. Lagom stora matningar ger all näring fiskar behöver, medan enbart en halt ammoniak som kan omvandlas till nitrit och därefter det relativt harmlösa nitratet uppstår snabbt nog för att vara ofarligt. De flesta - om än inte alla - fiskmatare på marknaden idag baserar sina portioner på enbart volym. På grund av variationer i mängden luft mellan foder så kan då mängden mat ha stor variation. Genom att lägga till en säkring med vikt, så kan vi helt och hållet motverka all risk för övermatning, och på så vis säkerställa ett långt och hälsosamt liv för våra husdjur. Överlag lyckades vi skapa ensäker fiskmatare, men dessvärre var inte vågen lika noggrann som den optimalt hade varit.
10
Littlefield, Joanne. „Raising Fish in the Desert: Aquaculture Yields Fish and Shrimp“. College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/622264.
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11
Brehm, Andrew. „Quick Xlthlx Fish“. VCU Scholars Compass, 2011. http://scholarscompass.vcu.edu/etd/2484.
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A sequence of short stories both fact and fiction leading to, resulting from, or having nothing to do with the three sculptures that comprise The Crescent Club, an installation for the Anderson Gallery.
12
Good, Joanne Elizabeth. „Replacement of dietary fish oil with vegetable oils : effects on fish health“. Thesis, University of Stirling, 2004. http://hdl.handle.net/1893/2005.
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The work presented in this thesis examined the effects of dietary fish oil replacement on fish innate and adaptive immune function, disease resistance tissue histopathology and fatty acid composition of lipids in peripheral blood leukocytes. Dietary trials with Atlantic salmon (Salmo salar), Sea bass (Dicentrarchus labrax), Atlantic cod (Gadus morhua) and Arctic char (Salvelinus alpinus) were conducted in which fish oil was replaced by rapeseed oil, linseed oil, olive oil, palm oil, echium oil or a mixture of these oils. A significant reduction in respiratory burst activity was most pronounced in salmon and sea bass fed high levels of rapeseed oil-containing diets. In addition, rapeseed and olive oil inclusion in the diets of salmon and sea bass significantly reduced the head kidney macrophage phagocytic capacity to engulf yeast particles. A reduction in prostaglandin E2 levels was found to be related to a reduction in macrophage respiratory burst activity in salmon fed linseed oil diets and sea bass fed a dietary blend of linseed, palm and rapeseed oils. Changes in macrophage function may be a contributing factor causing a reduction in serum lysozyme activity observed in some trials. No significant differences were detected in cumulative mortality of Atlantic salmon fed an equal blend of linseed and rapeseed oils challenged with Aeromonas salmonicida. However, resistance to Vibrio anguillarium was significantly impaired in Atlantic salmon fed a blended oil diet containing linseed, rapeseed and palm oil. The major histological difference of fish fed vegetable oil diets was the accumulation of lipid droplets in their livers. Dietary fatty acid composition significantly affected the fatty acid composition of peripheral blood leukocytes. Generally, fish fed vegetable oil diets had increased levels of oleic acid, linoleic acid and a-linolenic acid and decreased levels of eicosapentaenoic acid, docosahexaenoic acid and a lower n-3/n-6 ratio than fish fed a FO diet. In conclusion, the results from these studies suggest that farmed fish species can be cultured on diets containing vegetable oils as the added oil source. However, feeding high levels of some vegetable oils may significantly alter some immune responses in the fish, especially head kidney macrophage function, disease resistance and, in addition, may cause an increase in tissue histopathology.
13
Taylor, Ryan James. „Applications of fish scale analysis to understand growth dynamics of fish populations“. Thesis, University of Hull, 2012. http://hydra.hull.ac.uk/resources/hull:5771.
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The use of hard structures to derive ecological information about fish populations is a fundamental tool in fisheries assessment, specifically the back-calculation of fish lengths. This study highlights the potential errors associated with correction factors (c) because of poor sampling and provides a validation of (c) values. In addition, classical fisheries assumptions about the relationship between scale radius and fish body length were tested. As a result, variability or error of correction factors can be reduced by having a minimum of 30 samples with at least 4 age classes represented. Alternatively the (c) provided can be used as a standard (c) factor for each species, eliminating the variance caused by poor sampling. Finally, the development of standard intercept values (based on observation of juvenile fish) should be promoted to replace or validate mathematically derived (c). The ability to accurately determine the age and growth of fish is an important tool in fishery biology and therefore it is fundamental to this work that all steps should be taken to increase the accuracy of back-calculated length-at-age data and account for size when fish lay down scales. To account for potential error associated with a correction factor, larval fish were routinely sampled to identify patterns of squamation, providing preliminary reference data for correction factors used in back-calculation of fish length-at-age. Determination of the length at squamation for more specimens will allow for the derivation of standard correction factors for each species that can be used across the species’ distribution. Geometric morphometric (GM) analysis of fish scales has been shown to be a good discriminator of genera using a fixed landmark approach. However, freshwater fish scales are often irregular in shape; therefore it is not possible to identify identical locations on all individuals. This study provides evidence that scale morphology can be used to discriminate riverine fish species. The analysis of fish scale morphology is inexpensive, quick, non-destructive, and informative and could easily be added to existing monitoring programmes. This study highlights the potentially important and opportunistic information that can be gained from the GM analysis of fish scales. It is therefore anticipated that this study will be fundamental in shaping future fish population assessments. It is recognised amongst scientists that fish growth rates vary across a catchment, with species typically achieving greater growth rates in their ‘preferred’ habitats. Similarly, previous authors have identified that growth variation exists for different species and populations. This study has found that the geographic location of a river/region influences the growth rates of freshwater fishes commonly found in England. The method of constructing regional growth curves and subsequent statistical analysis discussed in this study should be adopted by fisheries scientists, because current national growth rates may be unachievable in specific regions. Furthermore, current national curves are inappropriate for growth and population analysis because they may be biased by an individual river and/or region. This study is one of the few studies to examine the differences between regional recruitment success, and found similarities and differences at both the regional and national level. With recruitment success a key requirement of monitoring fish populations under the WFD, it is hoped the information provided here will aid fisheries scientists to understand the factors affecting regional and national recruitment success. Studies on the impact of climate change on fish populations have typically focused on suggesting, rather than predicting, the effects on lentic species rather than lotic species. Furthermore, these studies often deal with American rather than European ecosystems. To address this, predicted changes in the climate of the UK were used to model likely influences on fish populations, expressed as the length of young of year (YOY) fish achieved by the end of the first growth period (May-September), juvenile and adult growth (annual growth increment, AGI) and recruitment success (year class strength, YCS), for three cyprinid fish. This study found that climate change is likely to increase the propensity for cyprinid fish to thrive, although the exact mechanism will depend on inter-annual variability in temperature rises and the timing of flow events. Notwithstanding the limitations of this study, it provides ecologists with a greater understanding of climate change and its potential impact on European, lotic fish populations.
14
Maghaydah, Sofyan. „Utilization of fish processing by-products for nutritional formulation of fish feed“. Online version, 2003. http://www.uwstout.edu/lib/thesis/2003/2003maghaydahs.pdf.
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15
Atton, Nicola. „Social learning in fish /“. St Andrews, 2010. http://hdl.handle.net/10023/946.
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16
Saracoglu, Kaan. „Bildanalyse von M-FISH“. [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=963153013.
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17
Mainwaring, Gary. „Aspects of fish haematology“. Thesis, Swansea University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627994.
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18
Burchfield, Monica R. „Fish from Deep Water“. Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/english_theses/100.
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These poems are lyrical narratives dealing primarily with the joys and sufferings of familial relationships in present and past generations, and how one is influenced and haunted by these interactions. There is a particular emphasis placed on the relationship between parent and child. Other poems deal with passion, both in the tangible and spiritual realms. The poems aim to use vivid figurative language to explore complex and sometimes distressing situations and emotions.
19
Chonlatee, Cheewasedtham. „Protein metabolism in fish“. Thesis, University of Aberdeen, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327299.
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20
Willis, Kedon Kevin. „Doan Trouble de Fish“. Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/50622.
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Doan Trouble de Fish is a collection of short stories examining the way of live for different Jamaicans in their home country and in America. The collection opens from the first-person perspective of a teenage boy struggling to understand his place amongst his group of friends in "Sat'day" and, in "'Ooman Conversation," ends with an omniscient look into the lives of a group of adult women struggling to maintain agency against the pressures of poverty. In between, we hear a boy recounting a dramatic beating from his mother, witness an encounter between a young girl and a "duppy" in the countryside, see the transformation of a man dressing in his wife's clothes to feel powerful, and are treated to guidelines on being a closeted homosexual in Jamaica. The diverse characters and points-of-view are meant to offer a tableau of what it's like to inhabit the island or to be a product of its environment.Jamaica is the unspoken character of Doan Trouble de Fish. But the more popular depictions of an island paradise are abjured in favor of urban squalor and uncompromising heat. The Jamaican environment is often harsh to the collection's characters, particularly to its women and non-masculine men. A concept underlying many of these stories is the liability of identity. A central theme to the collection is the maintenance of personal integrity in the face of an environment unwelcome to one's identity. Some characters find a way to forge ahead. Some are still trying to figure it out.
Master of Fine Arts
21
Hill, Simon John. „Large amplitude fish swimming“. Thesis, University of Leeds, 1998. http://etheses.whiterose.ac.uk/12760/.
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A fish swims by stimulating its muscles and causing its body to "wiggle", which in turn generates the thrust required for propulsion. The relationship between the forces generated by the fish muscles and the observed pattern of movement is governed by the mechanics of the internal structure ofthe fish, and the fluid mechanics of the surrounding water. The mathematical modell ing of how fish swim involves coupling the external "biofluiddynamics" to the body's internal solid mechanics. The best-known theory for the hydrodynamics of fish swimming is Lighthill's elongated body theory (Lighthill, 1975). In Lighthill's theory the curvature of the fish is assumed small and the effect on the fish of the vortex wake is neglected. Cheng et al. (1991) did not make these simplifications in developing their vortex lattice panel method, but the fish was assumed to be infinitely thin and its undulations of small amplitude. Lighthill's "recoil correction" is the addition of a solid-body motion to ensure that an imposed "swimming description" satisfies the conservation of momentum and angular momentum. A real fish is expected to minimize such sideways translation and rotation to avoid wasteful vortex shedding. Cheng and Blickhan (1994) found that the panel method model required a smaller recoil than did Lighthill's model. Our approach is to extend Cheng's model to large amplitude. Thus we include the effect of the wake on the fish, and the self-induced deformation of the wake itself. In studying the internal mechanics of the body we model the fish as an active bending beam. Using the equations of motion of cross-sectional slices of the body we can form a set of coupled differential equations for the bending moment distribution. At large amplitude the bending moment equations involve the tangential forces acting on the body (which may be neglected in the small amplitude version). Consequently we include the boundary layer along the fish in order to estimate the viscous drag directly. The panel method has been used successfully for the fluid mechanical calculations associated with large-amplitude fish swimming. We are able to use its results as input to calculate the bending moment distribution. The boundary layer calculations are based on a crude model; solutions to the large amplitude bending moment equations should also be considered in this light.
22
Tall, Janice. „Oxidative rancidity in fish“. Thesis, Liverpool John Moores University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521752.
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23
Karalazos, Vasileios. „Sustainable alternatives to fish meal and fish oil in fish nutrition : effects on growth, tissue fatty acid composition and lipid metabolism“. Thesis, University of Stirling, 2007. http://hdl.handle.net/1893/220.
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Traditionally, fish meal (FM) and fish oil (FO) have been used extensively in aquafeeds, mainly due to their excellent nutritional properties. However, various reasons dictate the use of sustainable alternatives and the reduction of the dependence on these commodities in fish feeds. Hence, the aim of the present thesis was to investigate the effects of the replacement of FM and FO with two vegetable oils (VO) and an oilseed meal on the growth performance, feed utilization, nutrient and fatty acids (FA) digestibility and tissue FA composition and metabolism in three commercially important European fish species. Specifically, in Experiment I crude palm oil (PO) was used to replace FO in diets for rainbow trout. In Experiments II and III FO was replaced with rapeseed oil (RO) in diets for Atlantic salmon at various dietary protein/lipid levels aiming also at further reductions of FM by using low protein (high lipid) diet formulations. In Experiments II and III the fish were reared at low and high water temperatures, respectively, in order to elucidate, also, the potential effects of temperature. Lastly, the effects of the replacement of FM with full fat soya meal (FFS) in Atlantic cod were investigated in Experiment IV. The results of the present thesis showed no negative effects on growth performance and feed utilization in rainbow trout when FO was replaced with PO. The dietary inclusion of RO improved the growth of Atlantic salmon, possibly, due to changes in the nutrient and FA digestibilities and FA catabolism while, the growth and feed utilization were unaffected by the dietary protein/lipid level. However, the growth of Atlantic cod was affected negatively by the replacement of FM with FFS. The proximate composition of the fish whole body was in most cases unaffected by dietary treatments. The changes in dietary formulations affected the dietary FA compositions and resulted in significant changes in the fish tissue FA compositions. It was clearly shown that the fish tissue total lipid FA composition reflects the FA composition of the diet, although specific FA were selectively utilized or retained in the tissues by the fish. These may have serious implications not only for fish metabolism and growth but also for the quality of the final product, especially in terms of possible reductions of n-3 HUFA.
24
Wise, Brent Stephen. „Age composition and growth rates of selected fish species in Western Australia“. Thesis, Wise, Brent Stephen (2005) Age composition and growth rates of selected fish species in Western Australia. PhD thesis, Murdoch University, 2005. https://researchrepository.murdoch.edu.au/id/eprint/410/.
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Growth typically varies considerably amongst the individuals in a population and between individuals in different populations of the same species, especially when those populations are found in environments in which the characteristics differ markedly. Although the annuli in hard structures are often used to age fish, such growth zones are not always clearly defined in these structures. Thus, in these cases, it is necessary to use alternative methods for ageing, such as analysis of modal progressions in length-frequency data. However, these types of techniques can usually only identify distinct size classes that correspond to an age class. They thus only enable an individual fish to be aged when it is a member of a discrete size cohort. Such a situation generally only applies to the younger age classes. This thesis reports the results of studies on a species that can be aged using the annuli in one of its hard parts (asteriscus otoliths), i.e. Cnidoglanis macrocephalus, and four species (Amniataba caudavitatta, Apogon rueppellii, Pseudogobius olorum and Favionigobius lateralis) for which it was necessary to use a method such as length-frequency analysis for ageing.
Cnidoglanis macrocephalus is an important recreational and commercial species caught in coastal marine and estuarine environments in south-western Australia. However, all previous detailed studies on the age and growth on this species have focused on estuarine populations. This thesis reports the results of a study of the biology of C. macrocephalus in Princess Royal Harbour, a marine embayment on the south coast of Western Australia. Samples of C. macrocephalus were collected from amongst the macroalgae that were removed from this highly eutrophic embayment by mechanical harvesters. Analysis of the reproductive and size composition data derived from these catches showed that spawning occurs between October and December and that fecundity ranged from 75 in a 384 mm fish to 465 in a 443 mm fish. Small fish (<200 mm) were rarely caught, reflecting the fact that the young of this species are difficult to capture.
Analysis of the trends exhibited by the marginal increments on otoliths showed that the number of annuli on this hard structure could be used to age C. macrocephalus. The samples of C. macrocephalus collected from Princess Royal Harbour contained female and male fish that had lived for up to 10 and 9 years in age and reached maximum lengths and weights of 523 mm and 745.3 g and 557 mm and 735.8 g, respectively. To overcome the paucity of small fish, von Bertalanffy growth curves were constructed using back-calculated lengths and employing the scale proportional hypothesis and body proportional hypothesis (see Francis 1990). The growth rates of females and males were slower than those in a nearby seasonally closed estuary (Wilson Inlet) and in a permanently open estuary on the lower west coast of Australia (Swan River Estuary). Yield per recruit analyses were conducted in order to ascertain what minimum legal lengths were appropriate for the capture of C. macrocephalus in Princess Royal Harbour, the Swan River Estuary and Wilson Inlet in order to sustain the stocks in those water bodies.
The age and growth of Amniataba caudavittata and Apogon rueppellii in the Swan River Estuary were determined by analysing the trends exhibited by modes in sequential monthly length-frequency data. This was achieved by employing MULTIFAN, which constrained the means of the lengths of the cohorts in successive monthly samples to a seasonal form of the von Bertalanffy growth curve. The resulting growth parameters derived by MULTIFAN were similar to those derived from the growth curves fitted to the means of the cohorts determined independently for each monthly sample by MIX.
The discreteness of the distributions and modes of size classes in length-frequency data for A. caudavittata and A. rueppellii enabled sound growth curves to be constructed for both of these species. The growth curves of these two sexes of both species were significantly different, with K being lower and L being higher for females. The trends exhibited by these growth curves emphasised that the growth of both species is highly seasonal, with little or no increase in length occurring during the cooler part of the year. The seasonal von Bertalanffy growth equations implied that 'negative growth' occurred in winter, but this is an artefact produced by size-related differences in offshore movements that occur at that time of the year.
The age and growth of two further species from the Swan River Estuary, Pseudogobius olorum and Favonigobius lateralis, were also studied. Since P. olorum and F. lateralis both spawn at different times of the year and these times (spring and autumn) are not regularly spaced during the year, they produce new 0+ recruits at two irregularly-spaced times of the year. Consequently, MUTLIFAN cannot be used to analyse the size-distribution data for these two gobiid species. Thus, MIX was used to identify the size classes present in sequential samples and to provide means for the length distributions of those size classes. von Bertalanffy growth equations were then fitted to the mean lengths at the inferred age of the males and females of each size class of each species. It was found appropriate to use the traditional von Bertalanffy growth curve for describing the growth of the product of the spring-spawning group of both species and a seasonal von Bertalanffy growth curve for that of the product of the autumn-spawning groups of both species.
The growth curves, when considered in conjunction with the trends exhibited by reproductive variables, demonstrate that female F. lateralis attains sexual maturity more rapidly and at a larger size than P. olorum. The majority of the female and male progeny of the summer and autumn-spawning groups of F. lateralis reach maturity when they are approximately 3 1/2 and 8 1/2 months old, respectively, compared with five and seven months old, respectively, for P. olorum.
Models, incorporating data on water temperature and salinity and the growth and reproduction characteristics of P. olorum and F. lateralis, were used to postulate how environmental factors might be regulating when these two gobiid species spawn. The results of these models support the conclusion that the bimodal timing of spawning of P. olorum in the upper estuary was regulated by water temperature, with spawning occurring between 20 and 25oC but inhibited by temperatures greater than 25oC. They also showed that, although water temperature also influenced the timing of spawning of F. lateralis in the lower estuary, the onset of spawning by this species only occurred when salinities had reached 300/00.
25
Wise, Brent Stephen. „Age composition and growth rates of selected fish species in Western Australia“. Wise, Brent Stephen (2005) Age composition and growth rates of selected fish species in Western Australia. PhD thesis, Murdoch University, 2005. http://researchrepository.murdoch.edu.au/410/.
Der volle Inhalt der QuelleAnnotation:
Growth typically varies considerably amongst the individuals in a population and between individuals in different populations of the same species, especially when those populations are found in environments in which the characteristics differ markedly. Although the annuli in hard structures are often used to age fish, such growth zones are not always clearly defined in these structures. Thus, in these cases, it is necessary to use alternative methods for ageing, such as analysis of modal progressions in length-frequency data. However, these types of techniques can usually only identify distinct size classes that correspond to an age class. They thus only enable an individual fish to be aged when it is a member of a discrete size cohort. Such a situation generally only applies to the younger age classes. This thesis reports the results of studies on a species that can be aged using the annuli in one of its hard parts (asteriscus otoliths), i.e. Cnidoglanis macrocephalus, and four species (Amniataba caudavitatta, Apogon rueppellii, Pseudogobius olorum and Favionigobius lateralis) for which it was necessary to use a method such as length-frequency analysis for ageing.
Cnidoglanis macrocephalus is an important recreational and commercial species caught in coastal marine and estuarine environments in south-western Australia. However, all previous detailed studies on the age and growth on this species have focused on estuarine populations. This thesis reports the results of a study of the biology of C. macrocephalus in Princess Royal Harbour, a marine embayment on the south coast of Western Australia. Samples of C. macrocephalus were collected from amongst the macroalgae that were removed from this highly eutrophic embayment by mechanical harvesters. Analysis of the reproductive and size composition data derived from these catches showed that spawning occurs between October and December and that fecundity ranged from 75 in a 384 mm fish to 465 in a 443 mm fish. Small fish (<200 mm) were rarely caught, reflecting the fact that the young of this species are difficult to capture.
Analysis of the trends exhibited by the marginal increments on otoliths showed that the number of annuli on this hard structure could be used to age C. macrocephalus. The samples of C. macrocephalus collected from Princess Royal Harbour contained female and male fish that had lived for up to 10 and 9 years in age and reached maximum lengths and weights of 523 mm and 745.3 g and 557 mm and 735.8 g, respectively. To overcome the paucity of small fish, von Bertalanffy growth curves were constructed using back-calculated lengths and employing the scale proportional hypothesis and body proportional hypothesis (see Francis 1990). The growth rates of females and males were slower than those in a nearby seasonally closed estuary (Wilson Inlet) and in a permanently open estuary on the lower west coast of Australia (Swan River Estuary). Yield per recruit analyses were conducted in order to ascertain what minimum legal lengths were appropriate for the capture of C. macrocephalus in Princess Royal Harbour, the Swan River Estuary and Wilson Inlet in order to sustain the stocks in those water bodies.
The age and growth of Amniataba caudavittata and Apogon rueppellii in the Swan River Estuary were determined by analysing the trends exhibited by modes in sequential monthly length-frequency data. This was achieved by employing MULTIFAN, which constrained the means of the lengths of the cohorts in successive monthly samples to a seasonal form of the von Bertalanffy growth curve. The resulting growth parameters derived by MULTIFAN were similar to those derived from the growth curves fitted to the means of the cohorts determined independently for each monthly sample by MIX.
The discreteness of the distributions and modes of size classes in length-frequency data for A. caudavittata and A. rueppellii enabled sound growth curves to be constructed for both of these species. The growth curves of these two sexes of both species were significantly different, with K being lower and L being higher for females. The trends exhibited by these growth curves emphasised that the growth of both species is highly seasonal, with little or no increase in length occurring during the cooler part of the year. The seasonal von Bertalanffy growth equations implied that 'negative growth' occurred in winter, but this is an artefact produced by size-related differences in offshore movements that occur at that time of the year.
The age and growth of two further species from the Swan River Estuary, Pseudogobius olorum and Favonigobius lateralis, were also studied. Since P. olorum and F. lateralis both spawn at different times of the year and these times (spring and autumn) are not regularly spaced during the year, they produce new 0+ recruits at two irregularly-spaced times of the year. Consequently, MUTLIFAN cannot be used to analyse the size-distribution data for these two gobiid species. Thus, MIX was used to identify the size classes present in sequential samples and to provide means for the length distributions of those size classes. von Bertalanffy growth equations were then fitted to the mean lengths at the inferred age of the males and females of each size class of each species. It was found appropriate to use the traditional von Bertalanffy growth curve for describing the growth of the product of the spring-spawning group of both species and a seasonal von Bertalanffy growth curve for that of the product of the autumn-spawning groups of both species.
The growth curves, when considered in conjunction with the trends exhibited by reproductive variables, demonstrate that female F. lateralis attains sexual maturity more rapidly and at a larger size than P. olorum. The majority of the female and male progeny of the summer and autumn-spawning groups of F. lateralis reach maturity when they are approximately 3 1/2 and 8 1/2 months old, respectively, compared with five and seven months old, respectively, for P. olorum.
Models, incorporating data on water temperature and salinity and the growth and reproduction characteristics of P. olorum and F. lateralis, were used to postulate how environmental factors might be regulating when these two gobiid species spawn. The results of these models support the conclusion that the bimodal timing of spawning of P. olorum in the upper estuary was regulated by water temperature, with spawning occurring between 20 and 25oC but inhibited by temperatures greater than 25oC. They also showed that, although water temperature also influenced the timing of spawning of F. lateralis in the lower estuary, the onset of spawning by this species only occurred when salinities had reached 300/00.
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Garaas, Marte, und Stevning Geir Ole Hiåsen. „Case-Based Reasoning in identifying causes of fish death in industrial fish farming“. Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for datateknikk og informasjonsvitenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-15401.
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Fish farming is a million dollar business world wide, and fish is in fact the third mostimportant export product after oil/gas and metal in Norway. There are a lot of different aquaculture sites which produce fish along our long coast line and they all have somedifferences in the production rates and procedures. The fish farmer at these sites holdvaluable information about the production, which is almost impossible to derive onlyfrom empirical data.In this thesis we introduce Glaucus, a Case-Based Reasoning system which aims tohelp the fish farmers with their decision making when conduction sorting operations attheir aquaculture sites. The system is built in Java and uses the jColibri developmentframework for Case-Based Reasoning. It retrieves cases based on similarity function frommyCBR and jColibri in addition to custom made ones. The case base is generated fromreal world data and the case queries are populated by a combination of user input anddata from a database with continuous data flow.Our approach is just the beginning of what we hope will be a even greater journeytowards a complete decision support system that will meet the expectations of the fishfarmers.Keywords: Case-Based Reasoning, Machine learning, Fish farming, jColibri, myCBR
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Bird, David Jonathan. „The response of fish to electricity and its applications in fish population ecology“. Thesis, University of Lincoln, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258772.
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Brownell, Lindsay Kirlin. „One fish, two fish, lungfish, youfish : embracing traditional taxonomy in a molecular world“. Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92629.
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Thesis: S.M. in Science Writing, Massachusetts Institute of Technology, Department of Humanities, Graduate Program in Science Writing, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 23-24).
In today's increasingly digitized, data-driven world, the "old ways" of doing things, especially science, are quickly abandoned in favor of newer, ostensibly better methods. One such discipline is the ancient study of taxonomy, the discovery and organization of life on Earth. New techniques like DNA sequencing are allowing taxonomists to gain insight into the tangled web of relationships between species (among the Acanthomorph fish, for example). But is the newest, shiniest toy always the best? Are we in danger of losing vital information about the world if we abandon the thousands of years of cumulative human knowledge to gather dust in basements? This thesis explores the current crossroads at which taxonomy finds itself, and offers a solution to preserve the past while diving headlong into the future.
by Lindsay Kirlin Brownell.
S.M. in Science Writing
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Pennock, Casey A. „Fragmentation and fish passage: can fishways mitigate discontinuities in Great Plains fish communities?“ Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/34557.
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Master of ScienceDepartment of Biology
Keith B. Gido
Fishways are a common tool for mitigating the effects of habitat fragmentation on fish communities, but their utility in low-gradient, sand-bed rivers of the Great Plains is not well studied. The Lincoln Street Fishway on the Arkansas River became operational in 2015 and was built specifically to pass small-bodied threatened fishes. We used a combination of surveys up-and downstream of the barrier and tagging experiments to test the ability of fishes to move into and through the fishway. Differences in fish community structure up- and downstream of the dam were more pronounced prior to the construction and operation of the fishway. In particular, Emerald Shiner Notropis atherinoides was absent from collections upstream of the dam before fishway construction, but commonly collected upstream in 2015 and 2016 surveys. Surveys within the fishway structure revealed 29 species, or 74% of the total species captured during our study were using the fishway. To further quantify fishway passage, we used a VIE experiment to assess if fish marked downstream of the fishway moved into or upstream of the fishway. Although we did not recapture marked fish upstream of the fishway, some marked individuals moved into the fishway. Finally, we conducted a PIT tag experiment to evaluate short distance movements within the fishway for three species of small-bodied minnow and were able to document upstream movement across a gradient of flows through the fishway. Results from our study illustrate the potential for fishways to mitigate the effects of habitat fragmentation on small-bodied fishes in sand-bed rivers.
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Wang, Xi-chang. „Comparisons of Quality of Kamaboko Gels Derived from Freshwater Fish and Marine Fish“. Kyoto University, 2001. http://hdl.handle.net/2433/150361.
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Cullis-Suzuki, Sarika. „Fish and ships : impacts of boat noise on the singing fish, Porichthys notatus“. Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/10526/.
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As anthropogenic ocean noise rises, research into its impacts on marine life is intensifying. Recent studies show concerning effects of noise on a variety of taxa, including fish. However currently lacking are in situ studies: the majority of fish studies have been lab-based, which lack the natural conditions and interconnections that put results in context. Further, the dearth of baseline information on natural fish sounds, communication and behaviours, limits predictions of noise impacts. Here I investigated the highly vocal plainfin midshipman (Porichthys notatus) in its natural habitat to determine the effects of boat noise on wild fish. Porichthys notatus uses sound to communicate during courtship and aggression, and depends on paternal care to safeguard nests in intertidal zones over several months. I first described acoustic communication features of P. notatus in situ by quantifying its vocalizations from longterm audio recordings gathered via hydrophones near a nesting site. I then characterized behaviours associated with acoustic signals by analyzing audio and video data of nest-guarding P. notatus. Finally, I determined the response of P. notatus to live motor-boat noise by examining behavioural and vocal activity of P. notatus in boat noise, ambient and control conditions. In addition to the manual analysis, I used an automated approach to determine overall movement of P. notatus under boat noise, ambient and control conditions. Findings reveal that when exposed to boat noise, fewer P. notatus predators were documented in the vicinity of P. notatus nests, while P. notatus increased overall time spent moving inside nests. Thus, noise benefits P. notatus indirectly by decreasing predator pressure, yet has direct negative impacts on P. notatus by increasing stress and metabolic costs. Such results reveal fitness consequences at both species and ecosystem scales, and indicate the importance of accounting for ecological relationships when predicting noise effects.
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Oxendine, Sharon L. Padilla Stephanie. „Exploring a fish model of developmental neurotoxicity using the Japanese medaka fish (Oryzias latipes)“. Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,676.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Curriculum of Toxicology." Discipline: Toxicology; Department/School: Medicine.
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Marshall, David William. „A study of the behavioural variables influencing consumer acceptability of fish and fish products“. Thesis, University of Newcastle Upon Tyne, 1990. http://hdl.handle.net/10443/725.
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The UK fishing industry has been fraught with difficulties over the past decade in the form of increased fuel prices, the imposition of catching quotas and the extension of Icelandic fishing grounds. In addition to thesep roblems,d emandf or fish in the LTKa ppearsto be in long term decline and Largely because of consumers rejection of many potentially edible species, and resistance to products containing fish. Yet few studies have attempted to identify the factors which determine acceptability of fish and fish products in the UK. This thesis addresses the issue of food choice and behaviour from the consumers perspective, identifying market trends in demand since 1977 and the current 'profile' of fish consumers. This is followed by qualitative research to identify the main issues which determine food acceptability with specific reference to fish, and the way in which fish fits into meal patterns. This work is then complemented by a study into food usage in one hundred households over a two week period, using food diaries to identify specific use of fish across meals and to verify some of the qualitative findings., A national survey of attitudes towards meat and fish helps to substantiate the qualitative findings and identify salient factors in food choice. The main findings highlight the restricted place of fish in the UK meal system and emphasise the importance of considering the overall appropriateness of fish for meal occasions. Fish is generally perceived as having a limited number of uses within the overall pattern of meals, and not to fit into the most common meal formats. The nature of meal occasions is changing as a consequence of wider social change. As major food events become less formalised, new opportunities are likely to arise for convenient fish products.
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Zha, Yinghua. „Assembly of Gut Microbial Communities in Freshwater Fish and Their Roles in Fish Condition“. Doctoral thesis, Uppsala universitet, Limnologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-314235.
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Animal hosts provide associated microorganisms with suitable ecological niches in their intestines. Microbes help their hosts to digest food, protect against pathogens, and influence the host’s metabolisms. Compositional variation of gut microbial communities is common among hosts, and may affect the health status of hosts. Diet and genetic factors are well known to influence the assembly of gut microbial communities. This thesis focuses on disentangling the contributions of factors including host genetics (sex), diet, environment, and other ecological processes to the assembly of gut microbial communities in freshwater fish. The association between gut microbial communities and fish condition is also evaluated in this thesis. Applying metacommunity theory, we found environmental factors including fish habitat, fish species, their diet, dispersal factors including microbes from fish diet, and ecological drift contributed to the assembly of fish gut microbial communities. The proportion of their contribution varied between fish species, where ecological drift explained more in perch than in roach. Under natural conditions fish populations face the risk of predation, which can induce competition and impose predation stress within prey individuals. This can therefore lead to changes in their diet qualities and quantities. In this thesis, it was shown that fish diet in terms of qualities and quantities significantly influenced the overall gut microbial composition, and this influence was dependent on fish sex, a host genetic factor. Predation stress was also suggested to significantly decrease the species richness. Furthermore, when fish were experiencing a diet shift, we showed that different bacterial phyla from novel food had different colonization success in the intestine, and this colonization success was positively influenced by predation stress. Fish condition was suggested in this thesis to be affected by gut microbial composition, especially by the contributions of the bacterial phyla Tenericutes and Actinobacteria.
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Arunachalam, Subbiah, und Jayashree Balaji. „Fish Science Research in China: How does it Compare with Fish Research in India?“ Jointly published by Akadémiai Kiadó, Budapest and Kluwer Academic Publishers, Dordrecht, 2001. http://hdl.handle.net/10150/105477.
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Fish and aquaculture research in the Peopleâ s Republic of China over the six years 1994-1999 has been mapped using data from six databases â three abstracting services and three citation indexes. The results are compared with fish science research in India. During the six years China has published 2035 papers (roughly 4.5 â 5% of the world output) and India 2454. More than 95% of Chinaâ s papers are journal articles, compared to 82.8% of Indian papers. About 78% of Chinaâ s journal paper output has appeared in 143 domestic journals compared to 70% from India in 113 Indian journals. Less than one-eighth of the journal articles published by Chinese researchers are published in journals indexed in SCI, compared to 30% of journal articles by Indian researchers. Less than a dozen papers from each of these countries have appeared in journals of impact factor
greater than 3.0. Fish research institutes and fishery colleges are the major contributors of the Chinese research output in this area. In India academic institutions are the leading contributors (61%), followed by central government institutions (>25%). Qingdao, Wuhan, Beijing and Shanghai are the cities and Shandong, Hubei and Fujian are the provinces contributing a large number of papers. As we do not have addresses of all authors in most of the papers, we are unable to estimate the extent of international collaboration. Although Chinaâ s research output and its
citation impact are less than those of India, Chinaâ s fish production and export earnings are far higher than those of India. Probably China is better at bridging the gap between knowhow (research) and do-how (technology and creation of employment and wealth). China is pretty strong in extension.
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Rinne, John N. „Nonnative, Predatory Fish Removal and Native Fish Response, Upper Verde River, Arizona: Preliminary Results“. Arizona-Nevada Academy of Science, 2001. http://hdl.handle.net/10150/296582.
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Nelson, Madeleine. „Som fisken i vattnet“. Thesis, KTH, Arkitektur, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-170347.
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Som fisken i vattnet, ett projekt som tagit sin utgångspunkt i att återigen skapa liv på Skeppsbrokajen. Förhoppningen med projektet har varit att skapa en fiskmarknad som inte bara är en mötesplats utan en attraktionskraft. Från tidig morgon till sen kväll sker ett skådespel av fiskaktiviteter. Projektnamnet Som fisken i vattnet har en historisk referens till fiskeköparnas sumpar, vilka fanns på platsen under början av 1900-talet. Marknaden har tack vare denna referens delvis placeras under befintlig kajnivå för att frigöra yta och skapa en lämplig miljö för livsmedel. Känsla av närhet till havet förtydligas genom en helglasad vägg, vilken är enda skyddet mellan Saltsjön och besökaren. Marknaden ligger i liv med kajen precis emellan två av Gamla stans gränder. Marknadens två våningsplan är anpassade för två typer av besökare; den snabbare förbipasserande kunden samt de kunder som vill uppleva marknaden till fullo. Visionen är att besökaren ska kunna följa fiskens rörelse och process bakom glasade väggar, från det att den kommer in till marknaden till förädling och försäljning.Baltic fish tank is a project generated with the aim to recreate vivacity at Skeppsbrokajen by adding a fish market that is not only a venue but also an attractive force within itself. From early mornings to late evenings the market will offer a scene of fishing activities. The project name Baltic fish tank has a historical reference to the fish buyers sumps, which existed on the site during the early 1900s. The market is therefore placed under the existing quay level to free space on the embankment as well as create a suitable environment for seafood. A glass wall is the only thing separating the Baltic sea from the visitor and heightens the feeling of closeness to the ocean. The marketplace is situated in between two of the Old Town's alleys. The floors of the building are designed for two types of visitors; the client passing by and the consumer who wants the full fish market experience. The vision is to enhance the visitors’ experience, allowing the consumer to follow the fish from the fisherman’s hand to the cold ice display out in the marketplace. The entire process including the gutting of the fish is easily followed through the glass walls adding to a full transparency.
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Coffin, Allison Beth. „Unconventional myosins in fish ears“. College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2445.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.Thesis research directed by: Biology. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Fidler, Larry E. „Gas bubble trauma in fish“. Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28659.
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Fish exposed to gas supersaturated water often experience a form of stress known as Gas Bubble Trauma (GBT). GBT is an acute condition involving various forms of bubble growth both internal and external to the animal. Theoretical models are developed which establish thresholds for bubble growth. These models apply to:
1. ) Bubble growth in the vascular systems of fish.
2. ) Bubble growth in the environmental water that can occur in the buccal cavity and between gill lamella.
4.) Overinflation of the swimbladder.
3. ) Sub-dermal bubbles that occur on external skin surfaces such as the opercular flaps, between fin rays and in the lining of the mouth.
In order to develop the models for general use, it was necessary to establish the effective size of nucleation sites and other physiological parameters contained in the bubble growth threshold equations. This was accomplished through a review of data from the scientific literature and a two phase experimental program.
The literature review resulted in the compilation of a database containing over 1000 records of supersaturation data on salmonids. Various filters based on length, species, total gas pressure (TGP), partial pressure of oxygen (PO₂) and other criteria were applied to the database. The filtering operations established the existence of GBT mortality thresholds and identified relationships between other experimental parameters. The results of this analysis suggest that a lower threshold occurs at a water TGP of 1.10 Atms. and a higher threshold occurs at 1.15 to 1.18 Atms. However, it was not established that the apparent mortality thresholds correspond to thresholds for bubble growth predicted by the theoretical models.
To make this correlation, a preliminary experimental study examined the physiological response of fish exposed to supersaturated water. It was found that arterial PO₂, hematocrit and blood pressure yield unique responses to bubble growth over specific ranges of water TGP. The results of these experiments also indicate that the lower mortality threshold of the database analyses is associated with a combination of sub-dermal bubble growth in the mouth and extracorporeal bubbles growing between gill lamella.
The second phase of experimental study included surveys of blood PO₂, hematocrit and pH along with microscopic studies of intravascular and extracorporeal bubble growth in gills. The results of these experiments confirm the source of mortality for the lower threshold at a water TGP of 1.1 Atms. In addition, the data demonstrate that the upper TGP threshold of 1.15 to 1.18 Atms. of the database analysis corresponds to the threshold for intravascular bubble growth. The results further confirm that, as predicted by the theoretical model, intravascular bubble growth thresholds are dependent on water PO₂ .
Combining the results of the database analysis and the experimental studies permitted the effective size of nucleation sites responsible for bubble growth to be back calculated from the theoretical equations. This completed the development of the bubble growth threshold equations. The equations can now be used to predict thresholds for the various forms of bubble growth and mortality that occur in fish exposed to supersaturated water. The experimental results also provide valuable information regarding the physiological response of fish to gas supersaturated water.Science, Faculty of
Zoology, Department of
Graduate
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Storey, Susan. „Spatial-temporal fish stock assessment“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ28463.pdf.
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Wagner, Glenn Nick. „Investigation of fish surgical techniques“. Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ43233.pdf.
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Adolfsson-Erici, Margaretha. „Fish bile in environmental analysis“. Doctoral thesis, Stockholm : Department of Applied Environmental Science, Stockholm University, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-494.
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Adam, A. K. M. „Giving Jonah the fish-eye“. Theological Research Exchange Network (TREN), 1987. http://www.tren.com.
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Sherwood, Graham D. „Fish energetics in polluted ecosystems“. Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38280.
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Conventional wisdom in ecotoxicology predicts reductions in organismal fitness to follow from exposure-related physiological effects. This expectation may be appropriate for controlled laboratory environments, but may not necessarily reflect what is likely to take place in the wild. In an extensive review of the ecotoxicology literature, it was revealed that fish condition factor (an index of energetic fitness) is just as likely to respond favourably to pollutant exposure as it is to respond negatively. The remainder of this thesis examines some of the ecological reasons for this apparent paradox. One possible cause of altered energetic status in wild, pollutant-exposed fish is variable food availability. Addressing this possibility, I showed that consumption rates (estimated using a 137Cesium mass-balance approach) were not related to growth reductions in hormonally-impaired yellow perch ( Perca flavescens) from metal-contaminated lakes. Another possibility is that fish forage less efficiently in metal-polluted lakes as a result of lowered prey choice. In this thesis, I develop an enzymatic and individual-based biomarker for fish activity costs (muscle lactate dehydrogenase, LDH, activity) and show, through the use of this tool that the cost of fish activity is intimately tied to prey type and the ability to make normal ontogenetic diet shifts. Through the application of LDH measurements, as well as through bioenergetic modelling, diet and prey community analyses, a link between decreased prey choice and high perch activity costs leading to zero growth efficiency (energetic bottlenecks) was demonstrated in yellow perch from metal-contaminated lakes. This finding provided one of the first examples in ecotoxicology of a mechanistic link between community and organismal endpoints. The findings of this thesis emphasize the need for ecotoxicology to consider ecology when looking for and interpreting ecologically relevant endpoints. The final chapter of this thesis ex
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Dunlop, R. A. „Stress and pain in fish“. Thesis, Queen's University Belfast, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269065.
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Mormede, Sophie. „Contaminants in deep water fish“. Thesis, University of Glasgow, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.392611.
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Ward, Ashley J. W. „Shoal choice decisions in fish“. Thesis, University of Leeds, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400150.
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Lindmark, Elianne. „Flow design for migrating fish“. Doctoral thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-25698.
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The utilization of rivers for hydropower production leads to problems for migrating fish, such as Atlantic salmon (Salmo salar) and sea trout (Salmo trutta). Both salmon and trout reproduce in fresh water, but spend their adult years at sea. To overcome man-made obstructions to and from the spawning grounds the fish needs help. Fishways for upstream migrating fish is an old technique; however the efficiency is often low due to inefficient attraction water. The upstream migrating fish are attracted to high water velocities and often approach the dominating flow from the turbine outlet instead of entering the fishway. For the downstream migrating smolt (young fish) the only way to pass a power plant is often via the turbines, with a high mortality as a result. The smolt follow the main flow in the river on the way downstream avoiding high accelerations or retardations. This thesis covers investigations on both an attraction channel to increase the water velocity at the inlet of a fishway for upstream migraters and a smolt guidance device to guide the smolt away from the turbine inlet to a safer passage route. To investigate the properties of the attraction channel both model and field experiments have been carried out, as well as numerical studies. The velocity in the channel has been examined with Laser-Doppler-Velocimetry and the flow field in the channel was studied using Particle-Imaging- Velovimetry. The results show that the water can be accelerated 38 % compared with the surrounding velocity. How far the increase in velocity is present depends on the depth of the attraction channel. The field tests carried out at Sikfors hydropower plant in Piteå River (Sweden) show that the fish do swim through the channel, providing that the channel is black. The flow around a smolt guidance device has been studied using numerical simulations. The aim of the device is to redirect the surface flow from the turbines to the spillway. By doing this, the shallow swimming smolt will also be guided towards the spillway and a much safer route. The results show that the guidance device successfully redirects the surface flow without creating any strong acceleration that may scare the fish.Godkänd; 2008; 20081113 (ysko)
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McGinley, Susan. „Tagging Fish: Monitoring Native Species“. College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2000. http://hdl.handle.net/10150/622273.
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Branco, Paulo José de Lemos. „Improving connectivity for river fish“. Doctoral thesis, ISA, 2013. http://hdl.handle.net/10400.5/6447.
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