Stevens, Ernest Donald

The purpose of this study was to describe the cardiovascular changes that occur when fish swim, and to determine some of the mechanisms by which these changes are regulated. Two levels of exercise were used: moderate and severe. Moderate exercise was induced by conditioning the fish to swim against a moderate water velocity (1.7 ft/sec) in a respirometer tube. The effects of severe exercise were studied by forcing the fish to swim by chasing it. Changes in blood pressures in the ventral aorta...

Mimeault, Caroline

Human pharmaceuticals have been reported in the aquatic environment but information pertaining to their effect(s) in aquatic non-target species was scarce when this project was initiated. The two main objectives of this research were to determine if these new emerging contaminants are available to aquatic species and to assess if exposure can lead to unfavourable effects in two fish species, the goldfish (Carassius auratus) and the rainbow trout (Oncorhynchus mykiss). Most studies were done with...

Stephenson, Jaynie M

As urban populations increase globally, the conversion of natural land cover to anthropogenic land use is on the rise. Diffuse perturbations that accompany such land use changes are considered a chief threat to headwater streams, which provide habitat for diverse faunas of macroinvertebrates, fish, and amphibians and are important sources of sediments, nutrients, and organic matter for downstream systems. Although environmental assessments of stream ecosystems generally measure responses to thes...

Levesque, Haude M

Fish are becoming more important in the human diet as they represent a high protein source and a source of essential free fatty acids. Fish production from aquaculture has been improved by the selection of faster growing individuals, but fish continue to remain an expensive nutrient source. A better understanding of fish growth mechanisms and regulation will help to further improve aquaculture techniques. Moreover, studying those factors that stimulate cells implicated in fish muscle growth coul...

Babineau, David

Weakly electric fish use a unique sensory modality in order to help them communicate, navigate and find prey. These fish emit electric discharges that are monitored by electroreceptors located in the fish's skin. Surrounding objects perturb these baseline transdermal potentials and create electric images. The study of these images has led to a better understanding of general sensory processing principles; however, many aspects of these fish's natural electrosensory environment remain unknown. T...

Gormican, Stephen Joseph

Fish farming in the protected waters of British Columbia is relatively new, but has undergone a phenomenal growth in the last ten years. Little investigation has been reported with respect to conditions within the net-cages employed in growing salmon at fish farms. In particular, the role of water quality and water exchange has not been examined in relation to local mariculture husbandry practices and hydrography. The first part of this study compared water quality and water flow in two locatio...

Merryfield, Jack William

An investigation has been carried out on the value and use of fish waste as a fertilizer. The material is a proteinate containing 10% nitrogen and originates as "offal", a by-product of the vitamin oil extraction process. The proteinate has been compared with commercial organic and inorganic fertilizers and certain conclusions have been reached. In addition, the minor element content, the manufacture of a complete fertilizer, and the possible feeding value of the material have been investigated...

Chan, Kenneth Ka-Sing

This study evaluates the toxicity, accumulation, chronic effects and mode of action of methylmercury on the reproduction of the teleost fish, Oryzias latipes. The median lethal concentration, 96h-LC50, for adult Oryzias was + 88+9.8 μg CH₃Hg⁺/1 as determined in a static system. Residue analysis by gas chromatography showed that fish exposed to 43 to 1000 μg CH₃Hg⁺/1 had tissue levels below 40 μg CH₃Hg⁺/g while fish exposed to more than 1000 μg CH₃Hg⁺/1 accumulated methylmercury steadily and ...

Prentice, Norman David Joseph

The effects of short term exposures to sublethal doses of mercuric chloride were studied using species of anadromous fish. Aspects of grou/th and behaviour u/ere used as indicators of physiological and psychological malfunctions due to mercurialism. The characteristic migration tendencies ( upstream or downstream ) of Lower Babine and Fulton River alevins were tested in experimental laboratory channels. The were conducted in a chamber in which a day, dawn through dusk, could be simulated. Each ...

Ssentongo, George William

Simple algebraic relationships and yield equations that require the minimum of data are developed so as to enable quick and reliable assessments of relative rate of harvesting tropical freshwater fish populations. The age of a fish at the inflexion point is inversely related to the growth rate (K) and directly related to the natural logarithm of the weight length exponent (b). Algebraic relationships between the exponent of anabolism (m) and the weight length exponent are developed. Equations...

Khoo, Hong Woo

The purpose of the study is to find out how Oligocottus maculosus homes and what mechanisms or sensory channels are involved in the homing process. The species' home range was defined from pool fidelity and movement observations. Evidence was obtained to show that the fish homes when displaced to unfamiliar areas. The roles of season, distance and direction of displacement as well as sex, size and experience of the fish in homing were assessed. The roles of both vision and olfaction and the rel...

Hofmeyr, Hendrik Petrus

The tolerances to sea water, sodium chloride and sodium sulphate of various cichlid, cyprinid and anabantid species which occur naturally in or near the Eastern Province region of Southern Africa, were determined, and correlated with their distribution ranges. Of the nine freshwater species tested, only Tilapia mossambica is able to disperse through the sea and is therefore the only member of the secondary division (Myers 1937) present in this region. The remaining species are possibly all limit...

Sutherland, Kate

The larval fish and zooplankton assemblages were studied in the permanently open Sundays Estuary on the south-east coast of South Africa, using standard boat-based plankton towing methods. A total of 8174 larval and early juvenile fishes were caught, representing 12 families and 23 taxa. The Clupeidae, Gobiidae and Blenniidae were the dominant fish families. Common species included Gilchristella aestuaria, Caffrogobius gilchristi, Omobranchus woodi, Liza dumerilii, Glossogobius callidus and Myxu...

Kellner, Martin

Selective serotonin re-uptake inhibitors (SSRIs) are a class of anxiolytic and anti-depressant drugs. SSRIs act on the evolutionarily ancient serotonergic system which is virtually identical throughout the vertebrate phylum. Serotonin is involved in a wide range of processes ranging from neuronal and craniofacial embryonic development to regulation of behaviour. However, SSRIs are also emerging pollutants, mainly entering the environment via sewage treatment plants. Since the serotonergic system...

Sullivan, Kevin M.

<p> River herring, the collective name given to North American populations of Alewife (<i>Alosa pseudoharengus</i>) and Blueback Herring (<i> A. aestivalis</i>), are iteroparous, anadromous members of the family Clupeidae, with similar morphology, ecological roles, and overlapping distributions. Once abundant in coastal rivers of New Hampshire, many factors including commercial fishing, habitat degradation, and dam construction resulted in a precipitous decline of the species along the entire co...

Gooskens, Imke

Includes bibliographical references. / This dissertation is based on an ethnographic study with children and young people between the ages of 11 and 19, who attend formerly 'white' state schools in the Cape peninsula, South Africa. Since 1994 these schools have seen an increase in the racial diversity of the student population, but children continue to live in a highly segregated landscape. I take a closer look at the way these schoolchildren work within and around divisions of class and race in...

Syvertson, Laura Maye

<p> Researchers on the Northwest Coast (NWC) are often interested in complex questions regarding social organization, resource intensification, resource control, and impacts of environmental change on resources and in turn human groups. However, the excavation strategies used on the NWC often do not provide the spatial and chronological control within a site that is necessary to document their variability and answer these research questions. The &Ccaron;&iuml;x^wicen site has the pote...

Gomez, Cristi Frasier

This dissertation examines the ability of in vitro biotransformation assays to provide an indication of metabolic potential. The potential for xenobiotic compounds to bioconcentrate in aquatic organisms is expressed through the bioconcentration factor (BCF). The metabolic loss of ibuprofen, norethindrone and propranolol was measured using rainbow trout (Oncorhynchus mykiss) and channel catfish (Ictalurus punctatus) gill and liver S9 fractions, microsomes and cell suspensions. Metabolic transf...

Kamula, R. (Riitta)

Abstract Fishways are hydraulic structures designed to dissipate the energy of flowing water in order to decrease water velocities and increase water depths. The history of fishways is long, the first written remarks date back to the 17th century. Fishway hydraulics, however, have been intensively studied only starting since the 1980's. Fishways have been classified into three main categories according to their hydraulic characteristics: pool-and-weir, vertical slot, and Denil fishways. Fis...

Esemu, Timothy

Includes abstract. / Includes bibliographical references. / This empirical study investigates the extent to which Ugandan fish and flower exporters are creating value and increasing their profitability through innovation activity and whether or not they are improving their ability to manage innovation projects effectively. It applied a mixed-methodological approach using a survey questionnaire and semistructured in-depth interviews administered on production, quality control, marketing and finan...

Driver, Lucas J.

This dissertation investigates the spatio-temporal dynamics of intermittent stream fish metacommunities in response drought-induced fragmentation and re-connectivity using both field and experimental approaches. A detailed field study was conducted in two streams and included pre-drought, drought, and post-drought hydrological periods. Fish assemblages and metacommunity structure responded strongly to changes in hydrological conditions with dramatic declines in species richness and abundance dur...

Mendez Sanchez, Jose Fernando

This study determined the effect of hypoxia on air-breathing onset and physiological and morphological characters in larvae of the air breathing fishes Trichopodus trichopterus and Betta splendens. Larvae were exposed intermittently (12/12 h daily) to 20, 17, and 14 kPa of PO2 from 1 to 40 days post-fertilization. Survival, onset of air breathing, wet body mass, O2, Pcrit were measured every 5 dpf. Hypoxia advanced by 4 days, and delayed by 9 days, the onset of air breathing in Betta and Tricho...

Watenpaugh, Donald E. (Donald Edward)

Physiological and behavioral effects of exposure of fathead minnows (Pimephales promelas) and channel catfish (Ictalurus punctatus) to selenate-selenium (Se) and nitrite were investigated.

In 1961 the Green River was poisoned and its native fishes killed so that the new Flaming Gorge Reservoir could be stocked with non-native game fishes for sportsmen. This incident was representative of water management in the West, where dams and other projects have been built to serve human needs without consideration for the effects of water diversion or depletion on the ecosystem. Indeed, it took a Supreme Court decision in 1976 to save Devils Hole pupfish from habitat destruction at the hand...

Lefébure, Robert

Both temperature and terrestrial dissolved organic carbon (TDOC) have strong impacts on aquatic food web dynamics and production. Temperature affects vital rates of all organisms and terrestrial carbon has been shown to alter the dynamics of phytoplankton and bacterial production and affect the trophic structure of planktonic food webs. As climate change predictions for the Baltic Sea suggests future increases in both terrestrial carbon run-off and increases in temperature, the aim of thesis was...

Laurenson, Lawrie Jon Bain

Colonisation theory relative to introduced populations was examined with a view to determining the usefulness of theoretical concepts in the prediction of the success of an invasion by a species. To this end, the Great Fish River, with reference to species introduced by the Orange/Fish Tunnel, was used as a case history. It was concluded that theoretical descriptions of population growth, control and decline are useful only when considering individual ecosystems or species. The highly variable n...

Macnaughton, Camille

Les organismes aquatiques sont adaptés à une grande variabilité hydrique et thermique des rivières. Malgré ceci, la régulation des eaux suscite des changements aux débits qui peuvent provoquer des impacts négatifs sur la biodiversité et les processus écologiques en rivière. Celle-ci peut aussi causer des modifications au niveau des régimes thermiques et des caractéristiques de l’habitat du poisson. Des données environnementales et biologiques décrivant l’habitat du poisson existent, mais elles s...

Monopoli, Matthew Stephen

Physiological experiments were conducted to measure the effects of low pH water upon Na⁺ fluxes and swimming performance in east coast neutral water banded kokopu, and west coast banded kokopu living in naturally acid water. This allowed comparisons to be made regarding the relative acid tolerance between the two population stocks. A morphological study of the gills using scanning electron microscopy and transmission electron microscopy was carried out on a limited number of fish to compare gill...

Roberts, May B.

As a region renowned for high biodiversity, endemism and extreme temperature and salinity levels, the Red Sea is of high ecological interest. Despite this, there is relatively little literature on basic broad scale characteristics of the biodiversity or overall reef fish communities and how they change across latitude. We conducted visual transects recording the abundance of over 200 species of fish from 45 reefs spanning over 1000 km of Saudi Arabian coastline and used hierarchical cluster anal...

Prihartato, Perdana

The nighttime distribution of vertically migrating mesopelagic fish in relation to nocturnal light was studied during a circumglobal survey, in the Red Sea, and in a fjord at high latitude. The study was based on data derived from ship borne echo sounders (circumglobal and the Red Sea) as well as using upward looking echo sounders mounted on the bottom (Masfjorden, Norway). We also applied a numerical model for analyzing diel vertical migration patterns. The effect of the lunar cycle was the foc...

Garrett, Robert Harry.

Phreatophytes in the western United States consume water at a rapid rate through transpiration and present a serious water wastage problem. Initial attempts to control wastage were through eradication by mechanical means. These methods met with little success due to high costs, regrowth abilities of phreatophytes and opposition from wildlife interests that consider phreatophyte vegetation essential wildlife habitat. Chemical antitranspirants, which would reduce phreatophyte transpiration without...

Hallock, Robert James,1943-

The purpose of this study was to evaluate the suitability of reclaimed domestic wastewater for a sport fishery. The water was reclaimed by a tertiary treatment of sand filtration. The fish tested were Channel catfish, Ictalurus punctatus, Rainbow trout, Salmo gairdneri, and Malacca Tilapia hybrids. The major objectives were to establish survival rates, growth rates, stocking schedules, and maximum stocking densities for these fish in an unusual and highly productive environment. Less than 1% sur...

Lewis, Steven A.

Four experiments were conducted to evaluate some of the effects of mechanical evaporation barriers on fish growth and pond productivity. Barrier coverages above 5O7 reduced fish growth, fish survival, aquatic insect yields, gross photosynthesis, dissolved oxygen concentrations, temperatures, and habitat areas. These reductions appeared to correlate with decreased amounts of light entering each pond. Zooplankton numbers, phytoplankton chlorophyll concentrations, pH, and turbidity measurements wer...

Gamboa Pulido, Pedro Miguel.

The development of a clinical diagnostic scheme for ciguatera fish poisoning has been accomplished through the utilization of three assays, specifically a competitive enzyme-linked immunosorbent assay (ELISA) for quantification, and two procedures for separation of toxic potentials, i.e., a liquid-liquid partition method and an immunoaffinity column system. For the ELISA assay, quality control parameters were evaluated including the coating binding efficiency and the binding capability of the co...

Sória Pérez, José A. (José Antonio)

This thesis deals with the automatic detection of features in signals, either extracted from photographs or captured by means of electronic sensors, and its possible application in the detection of morphological structures in fish otoliths so as to identify species and estimate their age at death. From a more biological perspective, otoliths, which are calcified structures located in the auditory system of all teleostean fish, constitute one of the main elements employed in the study and managem...

Gebremichael, E. T.

Exports of Eritrean fishery products, for which the European Union is the largest market, has an important share in the socio-economic development of the country. It is very important to earn foreign currency and provide employment opportunities by encouraging local and foreign investors in the sector. The export of fish from Eritrea mainly targets markets of developed nations where food quality and safety standards are increasing rapidly. During the last decade there has been more focus on the ...

Moloi, Puleng Cathrine

Lake Mzingazi is a freshwater coastal lake in Richards Bay, KwaZulu-Natal. Because of ongoing industrial and residential developments in the Richards Bay area, the need for potable water increased and led to the construction of a weir across the outlet of Lake Mzingazi. The first weir on this historically estuarine lake was built in 1955, after which it was raised several times to satisfy the increasing demand for water. Due to potential salt-water intrusion via groundwater from the saline Mzing...

Nhleko, Jabulile Blessed Busisiwe

The St Lucia estuarine system is considered to be the largest nursery area for estuarine-associated marine fish in southern Africa. The prolonged mouth closure due to regional droughts has resulted in large declines in its fish and prawn communities with deleterious consequences for regional marine populations, especially those that require estuaries for completion of their life cycle. Mouth closure of the St Lucia system contributed to a renewed interest in the St Lucia-Mfolozi System link, par...

Lin, HONGKANG

Alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) are major constituents of crude oil, and the 3-5 ringed alkyl-PAHs have been identified as the main components chronically toxic to fish. While chysene homologues have higher cytochrome P4501A (CYP1A) induction potencies than alkyl-phenanthrenes, there is little characterization of toxicity for 4-ringed alkyl PAHs. This study measured the chronic toxicity of chrysene, benz[α]anthracene, and some alkylated congeners to the embryos of Japanes...

Sharapov, Sergei

Following master thesis “Compact design of fish processing equipment and implementation of lean tools” contains description and technical information about newly developed fish processing equipment which includes 122 sub-assemblies and 626 parts. Completely new technical documentation was created and used to manufacture real and functional prototype. Main goal is to design new robust module, create correct and functional technical documentation, implementing new technical solution based on resea...

Quinn, Amie L., University of Lethbridge. Faculty of Arts and Science

Fish are exposed to multiple stressors in their environment. The interactive effects of pesticide exposure and increased temperature on the physiological stress response were investigated in a comparative field study with cold-water (whitefish, Prosopium williamsoni) and cool-water (sucker, Catostomus) fish from the Oldman River, Alberta, Canada, and in a laboratory study with rainbow trout, Oncorhynchus mykiss. Physiogical stress indicators were measured, and exposure to pesticides was estimate...

Darwish, Gamal S.

No description available.

Ho, Marian Louise Twiss.

No description available.

Hanson, John Mark, 1955-

Data taken from the literature were used to develop and evaluate models predicting fish biomass and yield, crustacean zooplankton biomass, and profundal macrobenthos biomass in lakes. Total phosphorus concentration and macrobenthos biomass/mean depth were the best univariate predictors of fish biomass and yield. Phosphorus concentration was also the best predictor of zooplankton and macrobenthos biomass. In experiments testing for inter- and intraspecific competition, conducted in situ at densit...

Rashid, Asim J.

A PCR approach using degenerate primers specific for the highly conserved pore and S6 transmembrane domains of K+ channels was used to assess the diversity of K+ channels in the electric fish Apteronotus leptorhynchus. DNA sequence analysis has identified nineteen K+ channel genes, each of which can be classified into one of the four major families in a similar distribution to that in mammals. Also, an Apteronotus brain cDNA library was constructed and screened with mammalian K+ channel probes. ...

Man-Yu, Yang

Thesis (M.A.)--National Taiwan University Graduate Institute of Ecology and Evolutionary Biology / Includes bibliographical references

Destun, Krystofer J.

No description available.

Deng, Xiaoying

No description available.

Murkin, Elaine J.

No description available.

Janowicz, Mariola E.

No description available.