Hague, Ashley Melissa

To better understand the operating mode of the deep oceans during fundamentally warm climate intervals, we present new Nd isotope data from Deep Sea Drilling Project and Ocean Drilling Program sites in the North Pacific to expand the reconstruction of water mass composition and structure during the early Cenozoic. Fossil fish debris from Sites 192, 464, 465, 883, 884 and 1208 (paleowater depths spanning 900 to 4000 m) were used to reconstruct the water mass composition from ~85 to 30 Ma. The...

Phibbs, James Robert

The main objective of this study was to investigate small-bodied fish caging as an approach to evaluate selenium (Se) bioaccumulation and speciation in native fish species inhabiting lakes influenced by uranium (U) milling effluent in northern Saskatchewan, Canada. In contaminated environments freshwater fish show a high propensity to accumulate Se beyond levels needed for normal physiological function. Maternal transfer of elevated Se concentrations to offspring can cause deformities and reduce...

Kwong, Wai Man (Raymond)

The overall goal of the present research project was to investigate the physiology of dietary iron absorption and its interactions with the uptake and metabolism of other divalent metals, especially cadmium, in freshwater fish, using rainbow trout (Oncorhynchus mykiss) as a model species. Using intestinal sac preparations, iron absorption was found to occur along the entire intestinal tract of fish, with anterior intestine being the major site of absorption compared to either mid or posterior in...

Bennett, Pamela Margaret

To assess potential impacts of effluents from Key Lake and McClean Lake uranium operations on freshwater systems, morphometric (weight, length, condition factor) and biochemical (total body lipids and triglycerides, liver triglycerides, muscle protein, muscle RNA/DNA ratio) measures of growth and bioenergetics were determined in young-of-the-year (YOY) fishes collected in fall and spring. It was predicted that fishes exposed to mining and milling effluents would be in poorer condition relative t...

Goertzen, Meghan Minetta

Previous studies at the Key Lake uranium mill (Saskatchewan, Canada) suggested the complex effluent discharged alters energetic stores of resident fish species. A second study at the same site demonstrated certain fish from lakes downstream of the mill produce larvae with elevated incidence of developmental deformities. The mechanisms by which energy homeostasis is affected in fish downstream of the Key Lake uranium mill are unknown, and the effects of deformities and altered metabolism on swimm...

Dubansky, Benjamin David

Analysis of integrative physiological responses is a valuable approach to studying the biological impacts of natural and anthropogenic stressors in biota. By measuring fluctuations in multiple physiological characteristics, we are able to predict the impact that exogenous stressors may have on organismal health. Laboratory studies are useful in studying the effects of a single or multiple stressor interactions in a controlled environment, although field-based studies allow for the understanding ...

Lassuy, Dennis R.

Documentation of the seasonal feeding habits and ability to assimilate algae are presented for the first time for a North American grazing stream fish. The chiselmouth, Acrocheilus alutaceus, begins feeding on algal matter in early spring and has deposited large fat reserves prior to an early summer spawning season. A sharp decline in body fat content is then associated with a reduction in food intake at the onset of spawning. A subsequent increase in food intake, possibly with a higher energy v...

Miller, Thomas Charles

Thyrotropin (TSH) is a glycoprotein hormone released from the pituitary gland to promote the synthesis and secretion of thyroid hormone. The existence of well-established peripheral mechanisms for regulation of thyroid hormone delivery to targets has called into question the significance of TSH as a primary regulator of circulating thyroid hormone concentrations in fish. However, relatively little is known about the regulation or action of endogenously secreted teleost TSH, largely due to lack...

Pease, Allison Ann

The distribution and abundance of stream fishes are influenced by many factors operating at multiple scales. Understanding how environmental variables influence the structure of stream fish assemblages is important for habitat assessment, stream restoration, and for predicting responses to environmental change. An emerging view in community ecology is that a focus on the functional structure of species assemblages in relation to environmental gradients may reveal more general patterns applicable...

Kobara, Shinichi

Overfishing of stock and decreasing biodiversity are grave concerns for the U.S. and the rest of the world. Understanding and applying spatial and temporal information of marine species’ reproductive ecology and critical life habitat is vital to the development of effective strategies for marine resource management. In the Caribbean, one of the critical science gaps hindering effective management is the lack of information on how environmental factors may make fish spawning aggregation (FSA) sit...

Nemoto, Keiichi

Area closures have been widely used in the management of migratory fish and conservation of endangered marine species, but very few economic models are available to assess the impacts of a closure because economists have paid little attention to complexities in fishery management, such as spatial heterogeneity in fish stocks and fleet dynamics. This study presents a spatial economic model that features (i) heterogeneously distributed stocks of multiple species, (ii) their movement across areas, ...

Jackson, Andrew

In the Oueme River, a lowland river in Benin, Africa, artificial ponds constructed in the floodplain (whedos) are colonized during the high-water period by a presumably random sample of fishes from the river channel. As water slowly recedes from the floodplain, fishes are isolated in whedos until they are harvested near the end of the dry season. I surveyed fishes in whedos and adjacent main-channel and floodplain habitats during two low-water (2008 and 2009) and one falling-water (2010-2011) pe...

Furuhjelm, Catrin

Background: A connection has been proposed between the increase of allergic disease and the altered composition of fatty acids in the diet in the westernised world. Less oily fish and more vegetable oil are consumed today compared to 50-100 years ago. Programming of the immune responses takes place very early in life and environmental factors, such as fish in the diet, have been suggested to protect from infant allergy. Aim: The general aim of this thesis was to assess the effects of maternal di...

Aursand, Ida Grong

The present thesis aims at using non-invasive and non-destructive NMR techniques to contribute to a further understanding of fish tissue composition and its characteristics. Moreover, it aims at investigating the water dynamics and the distribution of fat and salt in fish as affected by species, raw material quality and processing from both the chemical and the physical angle at the same time. The applicability of low-field NMR as a tool for the fish processing industry was investigated. The ben...

Kobayashi, Donald R

Plankton samples were taken in Kaneohe Bay, Oahu with a free-fall plankton net to investigate the finescale distribution of larval fishes around coral reefs. Daytime samples indicated that the post flexion larvae of two gobiids (Psilogobius mainlandi and an unidentified species, Goby-l) were significantly more abundant at stations immediately adjacent to reefs (near-reef) than at stations in open water off the reef. Postflexion gobiid larvae appear to be capable of resisting advection/dispersal ...

Watson, William

Nine series of vertically-stratified zooplankton tows were made with a closing net at a single station in southern Kaneohe Bay, Oahu, Hawaii, between 31 August 1973 and 11 April 1974. Sampling periods occupied from 12 to 26 hours, with tows usually taken at about 3 m intervals between the surface and a maximum depth of 10 m. A total of 21,254 fish larvae of 49 kinds was collected. Six species were abundant: Foa brachygrammus, Omobranchus elongatus, Callionymus decoratus, Caranx mate, Stolephoru...

Holmborn, Towe

The aim of this Thesis was to improve our understanding and assessment of feeding conditions for zooplanktivorous fish in the Baltic Sea. We investigated (papers I, II) the usefulness of biochemical proxies for assessments of growth and metabolic rates in the dominant Baltic copepod Acartia bifilosa. A predictive model (paper I) for egg production rate (EPR), based on body size, RNA content, and water temperature, was established using females of different geographical origin. This model demonst...

Olne, Karin, Flenner, Ida

Many prey species are able to develop different morphological structures as defence against for example predators. Some of these structures are induced only by individuals exposed to a predator. This phenomenon is called phenotypic plasticity. In this paper we examine whether cuticle thickness in Leucorrhinia dubia (Odonata) larvae differed between specimens caught in fish containing lakes and fish-free lakes respectively. We measured the thickness of the cuticle from four different parts of the...

Leung, Siu-yin, 梁小燕

published_or_final_version / Architecture / Master / Master of Landscape Architecture

Lai, Chi-pong, 黎志邦

published_or_final_version / Conservation / Master / Master of Science in Conservation

Yang, Yao, 楊瑤

published_or_final_version / Biological Sciences / Master / Master of Philosophy

Ye, Yisha., 葉伊莎.

published_or_final_version / Biological Sciences / Master / Master of Philosophy

Lam, Kwok-hung, Ken., 林國雄.

published_or_final_version / Real Estate and Construction / Doctoral / Doctor of Philosophy

Yeung, Yuk-leung., 楊旭亮.

published_or_final_version / Ecology and Biodiversity / Master / Master of Philosophy

Chau, Tak-han, Gloria., 周德嫻.

published_or_final_version / abstract / toc / Ecology and Biodiversity / Master / Master of Philosophy

Rothwell, Sarah Elizabeth

Whole animal, in situ and in vitro experiments were performed to investigate the dynamics of catecholamine release during anaesthesia and the consequent effects on the cardiovascular system of Chinook salmon. Blood pressure, heart rate, haematocrit, mean cell haemoglobin concentration (MCHC) and plasma catecholamine concentrations were used as indicators of cardiovascular function. In vivo experiments were performed to elucidate whether anaesthetic exposure per se stimulates catecholamine releas...

Knuth, Friedrich Alexander

<p> Marine Protected Areas (MPAs) are successful place-based management tools in protecting Essential Fish Habitat (EFH) from commercial and recreational fishing pressures. In the southeast Atlantic, the morphometric environment of the seafloor has been found to be a control on Essential Fish Habitat (EFH) (Sedberry and Van Dolah 1984). To this end, modern methods of acoustic data acquisition and morphometric analysis of the seascape are promising oceanographic techniques for identifying and del...

Goetz, Daniel Blaine

<p>Thirteen oxbow lakes, 7 deep (>3.0 m) and 6 shallow (< 1.5m), were studied in the Yazoo River basin (YRB) to identify if divergent water quality characteristics and fish communities were common occurrences. Shallow lakes repeatedly experienced wide diel fluctuations in temperature and oxygen, reduced Secchi depth, and greater levels of suspended solids, turbidity, and chlorophyll-a. Fish communities were mostly comprised of orangespotted sunfish, juvenile crappies, gars, and various backwater...

There is concern regarding exposure of aquatic organisms to chemicals that interfere with the endocrine system. Disruption of the endocrine system can lead to impacts on sexual development, altered hormone levels, intersex, and ultimately reproductive failure. While effects of endocrine disrupting chemicals (EDCs) on standard laboratory species have been subject of intense study, to this day there is a large gap in knowledge and a high degree of uncertainty regarding the sensitivity of wild fish...

Owens, Gregory Lawrence

The filtering of light by water is contingent on depth, direction and clarity. Consequently, fish must contend with a much more variable spectral world than terrestrial species. The gene family responsible for light sensitivity, the opsins, has expanded in fish. The duplication events responsible for large fish opsin gene repertoires have been characterized as part of this thesis research. The four-eyed fish, Anableps anableps, swims at the surface with its eyes at the waterline. Among many...

McMackin, Rebecca Alexia Giampietro

Consumption of mercury in fish in the human diet can cause developmental damage in fetuses and young children, cardiac infarction and infertility in adult men, and neurological damage in people in general. British Columbia does not have fish consumption advisories for sport-caught fish and province-wide testing of fish-mercury levels has not been conducted. Yet preliminary tests show that certain sport-caught fish have mercury concentrations above Health Canada guideline for normal consumption b...

Srean, Pao

This thesis aims to contribute to the understanding of the invasive success of two invasive fishes (Gambusia affinis and G. holbrooki). We reviewed four Internet databases and the literature to clarify their introduction history and geographical distribution, establish their introduction routes, and analyse predictors of their invasive success. A meta-analysis of the ecological impacts of mosquitofishes shows that the overall impact is: i) similar for the two species; ii) clear and strong for fi...

Brown, Philip, Järlskog, Ida

Chlorine gas bleaching was a common method used in pulp industries. As a consequence, significant amounts of chlorine were discharged into surrounding aquatic ecosystems, affecting the biota. Chlorinated organic pollutants are formed when chlorine react with organic material. Octadecanoic acid (stearic acid) is one of the most common saturated fatty acids in aquatic biota. In a naturally occurring process two and four chlorine atoms, respectively, are added over the unsaturated bonds, forming 9,...

Chung, Ming-long, 鍾名朗

published_or_final_version / Biological Sciences / Master / Master of Philosophy

Ho, Chi-fai, 何志輝

Since globalization have promoted the ornamental trade and accelerated the movement of freshwater fishes around the world, non-native species pose a high potential to be released into local freshwater habitats, and to spread and establish as invasive and nuisance species with adverse ecological, economic and social impacts. This study aimed to investigate the potential of the ornamental freshwater fish trade as an invasion pathway in Hong Kong, assess the ecological risk of common aquarium fresh...

Langland, Todd

The northwest Gulf of Mexico (Gulf) shelf-edge banks both provide unique hard bottom habitat and support the northernmost coral reefs on the North American continental shelf in a region that is generally characterized by low relief, soft sediments. The habitat value of many of these banks has led to their designation as Habitat Areas of Particular Concern (HAPC) and the Flower Garden Banks National Marine Sanctuary (FGBNMS). However, little is known about the fisheries resources and dynamics of ...

Costalago Meruelo, David

In the northwestern Mediterranean anchovy and sardine are among the most ecologically and economically important species. Both species are planktivorous during all their life stages, which could alledgedly lead to expect an overlap of trophic niches. However, trophic interactions between the two species had been, until now, poorly studied. This thesis aims to examine and compare the feeding behaviors of sardine and anchovy at different stages of their development, and during different seasons, i...

Alvarez, Maria Del Carmen

Not available / text

Fencil, Megan Christine

Due to high mortality encountered by marine fish larvae during their first weeks of life, small changes in the number of individuals surviving through this period can cause large fluctuations in year-class strength. Larval Red Drum (Sciaenops ocellatus) are dependent upon structured estuarine habitat to avoid predation. A study of post-settlement larval Red Drum distribution in a subtropical seagrass meadow in Mission-Aransas Estuary, Texas, USA indicates that larvae settle over approximately t...

George, Andrew Anthony

Although the processes used for temporarily storing and manipulating neural information have been extensively studied at the synaptic level far less attention has been given to the underlying cellular and molecular mechanisms that contribute to change in the intrinsic excitability of neurons. More importantly, how do these mechanisms of plasticity integrate with ongoing mechanisms of regulation of neural intrinsic excitability and, in turn, homeostasis of entire neural circuits? In this disser...

Dugan, Laura Elizabeth

Invasive species, a top threat affecting global biodiversity, become invasive through a process including four stages: transport, establishment, spread, impact and integration. Species currently in this process provide opportunities to empirically derive the mechanisms driving each of these stages, make predictions based on these mechanisms and then to test these predictions. This research examines the current invaded distribution, potential invasion and community-level impacts of a popular aq...

Howell, Taeya Marie

My dissertation focuses on self-perceived status as a driver for newcomers to initiate change in the organizations they join, either by trying to modify the tasks they are assigned to do (job crafting), implementing changes that affect how others do their work (taking charge), or making broader suggestions for improvement to the organization (voice). Although research has noted the actions that organizations take to socialize and to assimilate newcomers into the way things are conventionally do...

Moreau, Marie-Annick, 1976-

Conservation of the world's biodiversity is increasingly viewed as a development problem, requiring the alleviation of poverty together with the promotion of alternative livelihoods in resource-reliant communities. To be successful, such efforts must recognize the underlying logic of resource-users' livelihood choices. This study uses the activity of aquarium fish extraction in the Peruvian Amazon as a case study through which to examine the role that physical and non-physical assets (prim...

Chapman, Lauren J. (Lauren Jeanette)

This thesis demonstrates how the intermittent nature of seasonal tropical fresh waters facilitates and impedes the dispersal of fish and how the variability among residual dry season pools affects the dynamics of isolated populations. I focused on the seasonal ecology of Poecilia gillii from pools in a steep gradient, intermittent stream in Costa Rica. Water temperature and dissolved oxygen concentration were affected by season, by between-pool differences, and by the interaction between seasona...

Sareevoravitkul, Ramon

The growing demand for simulated fish products coupled with the declining stocks of traditional fish species for making these products, have increased efforts aimed at developing novel procedures to put non-traditional fish species like bluefish (Pomatomus saltatrix) and tilapia (Tilapia nilotica) to better economic use. Two procedures which fulfill both objectives are (i) application of high hydrostatic pressure, and (ii) utilization of protease inhibitor to control fresh fish spoilage due to m...

Carré, David

Schemes to restore fish habitat in rivers often involve installing instream structures such as current deflectors to create and maintain riffle-pool sequences. The presence of deep pools is a critical component of a high-quality physical habitat for fish as they provide shelter and cool temperatures during the summer months. Natural rivers exhibit many complexities that need to be taken into account when implementing instream structures. To improve the success rate of restoration schemes, many o...

Lee, Sang, 1972-

Members of the Dlg/PSD-95 protein family have a modular organization with multiple protein interaction domains and are thought to be important in the organization of synapses. A degenerate primer PCR strategy was used to screen for members of this family in the central nervous system of Apteronotus leptorhynchus, which possesses an electrosensory system that is well-suited for the study of synaptic organization and the subcellular localization of proteins. A. leptorhynchus was found to express a...

Kyei, Mary Abena.

Digestive proteases were isolated from the pancreas of the stomachless cunner fish (Tautogolabrus adspersus) and characterized in terms of their physicochemical properties, their ability to hydrolyze native pectin methylesterase (PME) from orange and polyphenol oxidases (PPO) from mushroom and the ability of the cunner enzyme(s) to maintain the stability of orange juice cloud. / The cunner trypsin fraction exhibited exceptional capacity to hydrolyze native proteins versus the bovine trypsin. Inc...

Hennigar, Julie Michelle

Headwater drainage features (HDFs) in the GTA are commonly subjected to land-use modifications including agricultural uses and urbanization. A temporal study design approach was used to test whether the runoff being exported from previously modified HDFs differed from runoff exported from less disturbed forested channels. Drift nets were deployed in the permanent reaches of streams and in the HDF channels, to give an indication of the quality and quantity of drifting materials. Gastric lavage...

Larson, Erik

Accurate sensory processing of the environment is a critical function for any organism to survive. In order to accomplish this function neurons must be specifically tuned to respond optimally to relevant stimuli in their environment. One effective way of efficiently encoding information is for neurons to adapt their responses to stimuli arising from different behavioral contexts. Neuromodulators such as serotonin (5-HT) are thought to help mediate such adaptations. The 5-HT system has been w...