Graham, M. A.

Estuaries in South Africa are important nursery areas for the juveniles of many fish species. The condition of many of these systems has, however, deteriorated as a result of degradation caused by urban, industrial and agricultural development. An assessment of the role of harbours, particularly in KwaZulu Natal, as nursery grounds has therefore become an important issue. Durban Bay has undergone considerable changes since the mid-1800s and further developments are proposed. If these developmen...

Freedman, Ryan

<p> Limited information exists on how southern Californian restored estuaries affect fish habitat use. I used the movements of five predatory fishes in two guilds (ambush and roving predators) to assess juvenile habitat use within estuaries and across landscapes at two spatial scales. Translocating fishes between two discrete estuaries located approximately I 0 km apart revealed that connectivity potential between sites differed between foraging guilds. Despite habitat design differences, fishes...

Mangerud, Gunhild

Improved and detailed knowledge regarding dietary mercury exposure in the Norwegian population is considered important as part of a national monitoring of exposure to hazardous environmental contaminants. Mercury is still regarded an important pollutant in Norway, reflected in the priority list for the Norwegian Pollution Control Authority (Norwegian: Statens forurensningstilsyn, SFT) from 1996. This priority list, defined politically by the Norwegian Parliament, includes about 30 different chem...

Parks, Candace R.

Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restr...

Bond, Stephen Raymond

The pannexins (Panx) are a family of chordate channel proteins with ancient homology to the invertebrate gap junction proteins called innexins. Only three distinct pannexin paralogs have currently been described in the Vertebrata, although all three are represented by orthologs in each of the major vertebrate clades. As public sequence databases have expanded however, a fourth pannexin sequence has revealed itself in teleost fish, apparently representing a duplication of Panx1. The first set of ...

Porteus, Cosima Sandra

Time domains of the hypoxic ventilatory response (HVR) are time dependent changes in ventilation that take place without changes in metabolic rate or arterial PCO2. Time domains of the HVR have been described in mammals along with their underlying mechanisms. Each time domain reflects a different change in the various steps in the control of breathing. Peripheral chemoreceptors are necessary for the expression of all time domains in mammals and changes in their sensitivity (reflected in releas...

Ahrens, Robert N. M.

Walters and Juanes (1993) proposed that heritable risk sensitive foraging behavior in juvenile fish could cause substantial delays in the recovery of a population i f selection has favored individuals with reduced foraging times while population abundance is low. They predict that such selection may occur in a over-exploited stock given the following conditions i.) spawning stock abundance has been eroded to a point where there is a reduction in juvenile density, ii.) reduction in juvenile ...

Weech, Shari A., Scheuhammer, Tony M.

Bald eagles and red-necked grebes were monitored from 2000 - 2002 on several lakes along the Pinchi fault, an area with a known source of geologic mercury and previous Hg mining (on Pinchi Lake), in an effort to discern whether increased Hg concentrations were affecting reproductive success and productivity. To determine whether or not Hg levels were elevated, fish tissues (rainbow trout and northern pikeminnow) were collected, eagles breeding on 5 lakes (Pinchi, Tezzeron, Stuart, Great Beav...

Healey, Peter

On April 14, 2008, British Columbia Environment Minister Barry Penner and Minister of State for Mining Kevin Krueger announced a $4.5-million remediation of the abandoned Mount Washington open pit copper mine in an effort to support the recovery of Vancouver Island fish stocks. The mine remediation will take place in three phases, between 2008 and 2010. The project will include the installation of a bituminous geomembrane that will cover the entire site. This will be covered by a one metre thick...

West, Timothy Gordon

The importance of circulatory glucose as a fuel for skeletal muscle and heart during sustained swimming and as a glycogenic substrate for skeletal muscle during exercise-recovery was examined. In vivo glucose utilization, using ¹⁴C-2 deox4yglucose (¹⁴C-2-DG), in swimming trout (Oncorhynchus mykiss) and carp (Cyprinus carpio) indicated similar rates of glucose utilization in red muscle of both species (20 - 30 nmol min ⁻¹g ⁻¹. Estimates of the energetic importance of glucose, assuming red mu...

Kroon, Frederieke Janet

In this thesis, I examine the occurrence of protogynous hermaphroditism in the blackeye goby, Coryphopterus nicholsii (Pisces, Gobiidae) at Bamfield, Vancouver Island, Canada. The female biased sex ratios, size distributions of female and male C. nicholsii, and histological data all confirm that the species is protogynous. Histological data strongly suggest two patterns of sexual ontogeny, with males resulting from either pre- or post-maturational sex change. Sex change is not common during...

Oikawa, Christopher Keiya

A procedure was devised to assess the efficacy of processed krill (Euphausia pacified) products as potential feeding stimulants for rainbow trout (Oncorhynchus mykiss) in a diet containing 60% plant material. Three experiments were conducted. Test substances were added in substitution for, on a dry weight basis, 2% of the fishmeal in the control diet, and were either mixed into the diet prior to pelleting, or coated on the pellet surface. Fish were fed to satiation once daily. Feed intake a...

Dong, Chunli

Spray marking of fish, using fluorescent pigment propelled by compressed air, is a mass marking technique, and is useful in the studies of fishery management. This method typically uses a conveyor system to transport fish into a marking unit that dispenses the powdered pigment through a nozzle with the aid of compressed air. The marked juvenile fish are then released to continue their life cycle, and may be subsequently caught for the purpose of experimental investigation. The previous desi...

Rohr, Annette Christine

The use of Semipermeable Membrane Devices (SPMDs) for monitoring pulp mill effluents containing potential fish tainting compounds was investigated. SPMDs are lipidfilled polyethylene bags which appear to mimic bioconcentration phenomena in aquatic organisms. They have been used as in situ, passive monitors of organic contaminants such as polynuclear aromatic hydrocarbons (PAHs) in aqueous environments, and were used here in a pulp mill setting. Preliminary method development work included ...

Lessard, Joanne

Carbonic anhydrase (CA) is absent in the plasma of vertebrates. In vitro, CA in fish plasma will short-circuit the effect of catecholamines on the increase in red blood cell (RBC) pH and volume, both of which increase the hemoglobin affinity for O₂. CA was infused into trout for a period of 6h during which the animal was submitted to deep hypoxia (PO₂= 30-35 torr) and during recovery after exhaustive exercise. During hypoxia, O₂ content, lactate, catecholamines, hematocrit, hemoglobin and ...

Kodama, David Michael Yuko

Methylmercury is a common contaminant found in fish. Chronic exposure can have detrimental effects on the nervous, cardiovascular and immune systems. Since mercury exposure can come from consuming fish that is caught as well as fish that is purchased, recreational anglers are a group that may have higher exposure than non-anglers. It was the primary goal of this study to determine whether exposure to methylmercury in Vancouver Island recreational anglers was greater from the consumption of sp...

Ishimura, Gakushi

The time variant/asymmetric distribution of a fish stock caused by ocean climate variability is one of the challenges that must be overcome to establish cooperative management of a transboundary fish stock. Pacific sardine (Sardinops sagax) exhibits extreme decadal variability in its abundance and geographic distribution that corresponds to water temperature regime shifts within the California Current Ecosystem. It is a transboundary fish stock and targeted by Mexican, American and Canadian fi...

Laberge Macdonald, Tammy

Glutamine synthetase is a key enzyme for nitrogen metabolism. It occurs in all organisms and is one of the oldest functioning genes. Many vertebrates have only one functional copy of this gene, while many plants have been shown to be multicopy for this gene. Pseudogenes for glutamine synthetase have also been reported in mammals. Until recently only a single copy of glutamine synthetase had been described in fish. However, six copies of this gene are expressed in rainbow trout Oncorhynchus mykls...

Parsonage, Kevin David

The focus of this research was to develop and test a method using image analysis to detect falling objects in a complex and variable underwater scene. This particular application involved the detection of fish-food pellets in netcage aquaculture systems. The problem was complicated due to the video camera positioning, number of other objects in the scene, and variable and uncontrollable background lighting conditions. The image analysis program was developed and tested using images obtained...

Wilson, Jonathan Mark

In my thesis the cellular and subcellular distributions of various ion transport proteins were determined in the fish branchial epithelium using an immunological approach employing non-homologous antibodies. The viabilities of current models of transepithelial ion transport in the gills of freshwater, and seawater fishes and an unusual amphibious air-breathing fish were tested. My thesis work primarily addresses the mechanisms involved in the translocation of Na+ and Cl- and their counterio...

Xiao, Dawn Dong-yi

Analyses of the evolution and function of voltage-gated sodium channel proteins (Navs) have largely been limited to mutations from individual people with diagnosed neuromuscular disease. This project investigates the carboxyl-terminus of the Nav paralog (locus scn4aa 3’) that is preferentially expressed in electric organs of Neotropical weakly-electric fishes (Order Gymnotiformes). As a model system, I used the genus Gymnotus, a diverse clade of fishes that produce species-specific electric orga...

Roy, Lucie H.

Goldfish, an exotic originally from Asia, are frequently released into North American waters, causing unknown impacts on native fauna and flora. In the wild, diet overlap between feral goldfish (Carassius auratus) and native red-spotted newts (Notophthalmus v. viridescens) is high, leading to potential interspecific competition over food. In the laboratory, we manipulated densities of goldfish and red-spotted newts to test competition for benthic food organisms between these unrelated species. /...

McNeil, Georgia

Understanding the role of divergent selection in the creation and maintenance of biodiversity is a central issue in evolutionary ecology. Cichlid fishes from the Great Lakes of East Africa are one of the foremost examples of rapid speciation in vertebrates, and their divergent male colour patterns have been credited with maintaining reproductive isolation. One approach to understanding the role of divergent selection in colour variation and to identify selective agents that may drive divergence,...

Smith, Scott A., 1978-

The relative importance of local, regional and historical processes to patterns of distribution and diversity of lower Mesoamerican (Panama and Costa Rica, LMA) freshwater fishes are examined at two different spatial scales. Biogeographic patterns of LMA freshwater fish communities at the spatial extent of LMA indicate that biological differences among species as well as regional and historical processes are quintessential to explaining the patters of turnover of community composition and ...

Picq, Sophie

The Neotropical knifefish Brachyhypopomus occidentalis is one of the few species of the highly diverse group of gymnotiform weakly electric fish that successfully colonized the freshwater basins of Central America, more specifically of Panama. Here, we inferred the phylogenetic relationships between populations of B. occidentalis in Panama to understand this species' evolutionary dynamics and resolve the timing and the mode of its colonization of the Central American Isthmus. We identified a hig...

Lee, Yun-ae

The fish processing industry is actively seeking for alternative methods of shelf life preservation and marketability of fresh fish, while at the same time economizing on energy costs. Two methods which fulfill both objectives are modified atmosphere packaging (MAP) and glucose oxidase (GOX)/Glucose dipping solutions. MAP is the packaging of perishable products in an atmosphere other than that of air and is used for the shelf life extension of beef, pork, fruits, vegetables and bakery products. ...

Watts, R. Dean

With increased urban development in the Fraser River Basin, it is expected that fish habitat degradation will become more widespread bringing into question the sustainability of the fisheries resource. This thesis examines the dynamics of land use and fish habitat in the Salmon River watershed located in the Lower Fraser River Valley. The study was initiated to:1) quantify the distribution and recent trends in land use changes; 2) identify and quantify critical fish habitat to provide a basis fo...

Foster, Michael D.

A system which quantifies the number of food pellets eaten by salmon in a sea cage would be beneficial to both fish farmers, and researchers. Such a system could be used for reducing food wastage, determining time-related feeding patterns, ensuring fish receive the correct dosage of drugs, etc. We developed algorithms for detection and counting of food pellets from recorded video image sequences, which could be used to determine actual feeding rates in a sea cage. The number of food pellets eate...

Tetreault, Gerald

Aquatic receiving environments have long been used to dilute municipal wastewater effluents (MWWE) which are the largest discharge by volume into the aquatic environment in Canada. These treated effluents are a complex mixture of environmental contaminants that includes natural and synthetic hormones, pharmaceuticals, industrial chemicals, nutrients and ammonia. Discharge of MWWE may lead to serious problems in aquatic environments such as eutrophication, hypoxia as well as increased occurrenc...

El-Sweisi, Wail

As fish cell cultures continue to be explored as alternatives to whole fish for evaluating the toxicity of environment chemicals, technical issues have emerged that influence results and thus need to be understood and standardized. These include carrier solvents, dosing protocols, exposure vessel, exposure media, viability endpoints, and cell lines. Some of these factors have been explored in this thesis for eight reactive contaminants exhibiting varied physicochemical properties using the rai...

Kawano, Atsushi

An intestinal cell line from rainbow trout, Oncorhynchus mykiss, was developed and challenged against several bioactive components. Primary cultures initiated from the distal segment produced the cell line, RTgutGC. RTgutGC showed optimal growth in L15 supplemented with 10-20% fetal bovine serum (FBS) at room temperature. RTgutGC has undergone over 100 passages and stained minimally for β-galactosidase, suggesting this to be an immortal cell line. Late passage cultures gave a consistent poly...

Metherel, Adam Henry

Omega-3 fatty acids, particularly docosahexaenoic (DHA) and eicospentaenoic acid (EPA), are important mediators for cardiovascular disease, fetal/infant development, neurological disorders and inflammatory diseases. Supplementation and washout studies are important for future research on the physiological effects of omega-3 fatty acids and for determination of the proper washout period for future cross-over studies. In this study, omega-3 fatty acid blood biomarker comparisons are made for the...

Wiseman, Steve

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs) are widespread in aquatic systems. These toxicants bioaccumulate in the tissues of aquatic organisms, especially fish as they occupy a position near the top of the aquatic food web. Teleost fish respond to stressors, including toxicants, by activating a co-ordinated network of adaptive responses, collectively termed the integrated stress response, which allows animals to regain homeostasis. Depending on the nature o...

Doñate Jimeno, Carmen

Los peces son claramente el grupo más exitoso y diverso de vertebrados, representando el 40% de todas las especies de vertebrados y mostrando un impresionante nivel de diversidad en distintos aspectos biológicos. Exhiben un gran número de particularidades genómicas únicas entre los vertebrados, que presentan a los peces como un modelo muy interesante para diversas disciplinas, en particular aquellas relacionas con la evolución. Por estas razones, algunas especies de peces han tenido un papel muy...

Ribas Cabezas, Laia

Aquesta tesis doctoral està basada en estudiar la resposta immunològica dels peixos en models d'estrès i d'activació del sistema immune des la genòmica funcional. L'aplicació de tecnologies moleculars com el Differential Display van permetre identificar y clonar por primera vegada en orades (Sparus aurata) y en altres especies de peix, el gen enolasa. Aquest enzim glucolític s'ha plantejat per primera vegada com un bon marcador molecular per estudiar el benestar dels peixos. Per mitjà de l'ús d'...

Johansen van Delft, Tord

Moisture control of industrial processes is often difficult and complex. The product composition and moisture content changes as disturbances affect the upstream production processes. When there are changes in the product content, simple control configurations may not work due to changes in the drying characteristics of the product. This thesis presents a general conveyor-belt dryer model describing a six-zone multiple-pass dryer, accounting for the falling rate drying period, input disturbances...

Jenkelunas, Peter

Frozen storage has long been used as a means to slow down the microbial and enzymatic degradation of fish. Unfortunately, over time frozen fish will lose protein solubility and water holding capacity leading to declining quality. To minimize the degradation of frozen fish, cryoprotectants (often a blend of sucrose and sorbitol) are employed. Although successful in limiting protein denaturation and aggregation, sugar based cryoprotectants are not suitable for diabetics or those who dislike sweet...

Qu, Qingming, Zhu, Min, Wang, Wei

Recent discoveries of early bony fishes from the Silurian and earliest Devonian of South China (e. g. Psarolepis, Achoania, Meemannia, Styloichthys and Guiyu) have been crucial in understanding the origin and early diversification of the osteichthyans (bony fishes and tetrapods). All these early fishes, except Guiyu, have their dermal skeletal surface punctured by relatively large pore openings. However, among these early fishes little is known about scale morphology and dermal skeletal histolog...

Cocke, William Gary

I examined the top down effects of fish predation and the bottom up effect of nutrient addition on emergent insect-mediated methyl mercury (MeHg) flux from experimental ponds. To determine the effect fish, emergent insects were collected from ponds with (n=5) and without fish (n=5) over a five to six-week period in 2011-2012. To determine the effect of nutrients, I fertilized six of the ponds in 2012 (three ponds with and without fish) and used four ponds as unfertilized controls (two ponds with...

Gao, Kai

Aquatic wildlife are exposed to contaminants in their natural habitats, and toxic pollutants may induce toxicity in sensitive target tissues and cells. There is therefore a need to establish biomarkers to determine exposure to certain classes of contaminants and the subsequent biological responses. In the present work the whole suite of cytochrome P450 1 (CYP1) genes expressed in fish were examined with regard to their inducibility and potential use as biomarkers. Complementary DNA of the CYP1A,...

Henderson, Byron Lee

The purpose of this study was to examine mercury in macroinvertebrate communities from grassland ponds with and without fish communities. We sampled macroinvertebrates from five ponds with fish and five ponds without fish, at the LBJ National Grassland in North Texas. In ponds without fish, the biomass of macroinvertebrates was significantly higher than in ponds with fish. The average mercury concentration of macroinvertebrates from ponds without fish was significantly higher than the average me...

Plath, Martin, Hermann, Bernd, Schröder, Christine, Riesch, Rüdiger, Tobler, Michael, García de León, Francisco J., Schlupp, Ingo, Tiedemann, Ralph

Background: Local adaptation to divergent environmental conditions can promote population genetic differentiation even in the absence of geographic barriers and hence, lead to speciation. Perturbations by catastrophic events, however, can distort such parapatric ecological speciation processes. Here, we asked whether an exceptionally strong flood led to homogenization of gene pools among locally adapted populations of the Atlantic molly (Poecilia mexicana, Poeciliidae) in the Cueva del Azufre sy...

Larimer, Amy Beth

The Laguna Madre is a hypersaline lagoon. Despite harsh conditions, the upper Laguna Madre (ULM) is a highly productive ecosystem and a popular sportfishing area, especially for spotted seatrout and red drum. It is also the most important Texas bay for commercial fishing of black drum. TPWD’s Coastal Fisheries division began conducting routine monitoring of coastal fishery resources in 1977 to guide management. The goal of the present study was to improve understanding of spatiotemporal trends i...

Telli, Murat

Evolutionary models addressing interaction between genetics and morphology propose that during development, morphological traits of organisms are under canalization selection resulting in constancy in morphology through evolutionary time. The hypothesis of genetic homeostasis predict that because of developmental buffering effects of heterosis, high level heterozygosity results in low level of morphological variance from the norms of canalized shape of the population. The aim of the present stud...

Kepenek, Ayse Ozge

Chemical communication in aquatic organisms has been topic of a large number of studies focusing interactions between organisms via info chemicals. Diel Vertical Migration (DVM) is commonly observed among zooplankton and consists of a single daily ascent with minimum depth reached between sunset and sunrise and a descent with maximum depth attained during the day. DVM was absent or reduced when predators were absent and well developed in their presence. Species of the Daphnia are one of the well...

Karapinar, Burcu

In this study, annual total phosphorus (TP) budget and dissolved inorganic nitrogen (DIN) load were constructed for Lakes Mogan and Eymir for the period of eight years from 1997 to 2004 and the period of ten years covering from 1993 to 1995 and 1997 to 2004, respectively. Lake Mogan experienced seasonal and interannual water level fluctuations. Low water level experienced in 2001 led to decrease in the in-lake TP amount whereas 2-fold increase in the in-lake DIN amount was recorded. Also, high h...

Meléndez, Guillermo Quinteros, 1967-

Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1998. / Includes bibliographical references (leaves 54-56). / by Guillermo Quinteros Meléndez. / M.C.P.

Rapo, Mark Andrew

Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 2009. / This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. / Includes bibliographical references (leaves 264-277). / The lateral line system on fish has been found to aid in schooling behavior, court...

Reichert, Steffen H. (Steffen Heinz)

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2010. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 98-101). / This thesis is about designing structures that combine the dual functions of mechanical protection and flexibility of motion. The structures are inspired by principles observed in the ganoid squamation (scale assembly) of an ancient fish species called Polypteridae, which first appeared 96 million years ago. Prior work on ...

Perez, Christina R., Perez, Christina R.

Recently, examination of deoxyribonucleic acids in water samples (environmental DNA or eDNA) has shown promise for identifying fish species present in water bodies. In water, eDNA arises from bodily secretions such as mucus, gametes, and feces. I investigated whether eDNA can be effective for characterizing fish presence, relative abundance, biomass, and species composition in a large Arizona reservoir (Theodore Roosevelt Lake) and 12 small Arizona (<24 ha) waterbodies. Specifically, I compared ...