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Aquaculture and Fisheries

Theses/Dissertations

2013

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Articles 1 - 12 of 12

Full-Text Articles in Ecology and Evolutionary Biology

The Genetic Architecture Of Juvenile Migration In Rainbow Trout (Oncorhynchus Mykiss), Benjamin Charles Hecht Oct 2013

The Genetic Architecture Of Juvenile Migration In Rainbow Trout (Oncorhynchus Mykiss), Benjamin Charles Hecht

Open Access Dissertations

Animal migrations play a critical role in the health and balance of ecological systems and in the evolution and diversification of species, and this is perhaps best displayed amongst salmonid fishes (salmon, trout, and char) who exhibit variation in the propensity to migrate both within and among species. Rainbow and steelhead trout (Oncorhynchus mykiss), members of the salmonid family of fishes, capture this variation throughout their native range. Some populations and ecotypes will remain resident in freshwater habitats throughout their life history; while others have the ability to embark on tremendous marine migrations. Those that migrate undergo a suite of …

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Changes In The Lake Michigan Trophic Structure: As Revealed By Stable C And N Isotopes, Benjamin Turschak May 2013

Changes In The Lake Michigan Trophic Structure: As Revealed By Stable C And N Isotopes, Benjamin Turschak

Theses and Dissertations

Food web structures which incorporate both slow (nearshore or detrital) and fast (pelagic) energy channels convey stability upon food web biota through asynchrony and multichannel trophic omnivory. Within the Lake Michigan food web, invasive dreissenid mussels have caused rapid changes to food web structure and energy flows. I used stable C and N isotopes and gut content analysis to determine how Lake Michigan food web structure and stability has changed in the past decade, coincident with the expansion of dreissenid mussels and a decrease in pelagic phytoplankton production. Fish and invertebrate samples collected near the port of Milwaukee, WI were …

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Comparative Phylogeography Of The Emperor Snappers Lethrinus Lentjan And Lethrinus Harak (Lethrinidae: Percoidei) In The Coral Triangle, Andrew B. Hines Apr 2013

Comparative Phylogeography Of The Emperor Snappers Lethrinus Lentjan And Lethrinus Harak (Lethrinidae: Percoidei) In The Coral Triangle, Andrew B. Hines

Biological Sciences Theses & Dissertations

Many questions remain regarding the origins of the well-known peak in marine biodiversity found in the Coral Triangle. Barriers to gene flow may promote lineage diversification and provide the potential for speciation contributing to the high biodiversity in this area. Population structure was examined in two species of Emperor Snappers (Lethrinidae), Lethrinus harak and Lethrinus lentjan. These species were selected because they share similar life-history traits and geographic distributions, but differ in their habitat preferences. Specimens were collected from within the Coral Triangle as well as other localities across the Indo-Pacific. To investigate phylogeographic patterns and structure a hypervariable …

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Evaluating The Effects Of Road Crossing Structures On Stream-Associated Amphibians In The Wilson River Watershed, Tillamook State Forest, Oregon, Sara Erin Twitchell Mar 2013

Evaluating The Effects Of Road Crossing Structures On Stream-Associated Amphibians In The Wilson River Watershed, Tillamook State Forest, Oregon, Sara Erin Twitchell

Dissertations and Theses

As replacement and removal of undersized culverts gains momentum as an effective technique for restoring natural stream flows and removing fish passage barriers, it is important to evaluate the benefits of these efforts on the in-stream and adjacent riparian habitat for other species of potential concern. This study compares stream-associated amphibian (SAA) occurrence in streams adjacent to different road crossing structures on unpaved forest roads in the Wilson River watershed located within the Tillamook State Forest, Oregon. Surveys were conducted at road crossing structures for three taxa of SAA; Pacific giant salamander (Dicamptodon tenebrosus), coastal tailed frog (Ascaphus truei), and …

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Size And Age Variation Of Larval Gyrinophilus Porphyriticus Porphyriticus In Sympatry With Salvelinus Fontinalis, Aaron Jacob Semasko Jan 2013

Size And Age Variation Of Larval Gyrinophilus Porphyriticus Porphyriticus In Sympatry With Salvelinus Fontinalis, Aaron Jacob Semasko

Theses, Dissertations and Capstones

The Northern Spring Salamander (Gyrinophilus porphyriticus) has a larval stage that could extend up to six years, an anomaly unheard of in other plethodontid salamanders. The size of a larva could be larger than an adult of a younger age. A sympatric species, Salvelinus fontinalis, the native brook trout, negatively alters the individual mass and survival of G. p. porphyriticus larvae. In the absence of trout, the role of G. porphyriticus ascends to top predator in a small stream community. Amphibians specifically have proven their role as stream indicators, a position attributed to their porous skin. I attempted to determine …

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The Crayfishes Of West Virginia’S Southwestern Coalfields Region With An Emphasis On The Life History Of Cambarus Theepiensis, David Allen Foltz Ii Jan 2013

The Crayfishes Of West Virginia’S Southwestern Coalfields Region With An Emphasis On The Life History Of Cambarus Theepiensis, David Allen Foltz Ii

Theses, Dissertations and Capstones

Crayfish are the third most endangered faunal group in the world behind freshwater snails and unionid mussels. A better understanding of each species’ life history is vital in order to aid in crayfish conservation; however, little to no life history information is available for most crayfish. Recently, an undescribed species of crayfish, Cambarus theepiensis, was discovered in the Cumberland Mountains of West Virginia and Eastern Kentucky. In conjunction with the species’ scientific description, life history data was collected from May 2012 through April 2013 from two sites located within the Twelvepole watershed of southwestern West Virginia. Animals were collected monthly …

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Filling In The Gaps In Phenology And Life History Of The Cumberland Plateau Salamander (Plethodon Kentucki), Robert C. Bowers Jan 2013

Filling In The Gaps In Phenology And Life History Of The Cumberland Plateau Salamander (Plethodon Kentucki), Robert C. Bowers

Theses, Dissertations and Capstones

The Cumberland Plateau Salamander, Plethodon kentucki, is a member of the Plethodon glutinosus complex comprising 16 sibling species, which are best differentiated by range. Few studies have been conducted to gain information on the natural history of P. kentucki. To alleviate this, two sites at Beech Fork State Park in Wayne County, West Virginia were used to study the salamander’s general life history with emphasis on reproduction, phenology, and population size. At each site, three 20m x 20m sample plots were arranged based on viability of the habitat for P. kentucki. Ground searches of all cover objects …

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Examining The Influence Of Mating Systems On Testes Size In Salamanders, Howard James Stanton Ii Jan 2013

Examining The Influence Of Mating Systems On Testes Size In Salamanders, Howard James Stanton Ii

Theses, Dissertations and Capstones

Sperm competition theory predicts that relatively larger testes sizes evolve in animals with polygamous mating systems compared to those in monogamous mating systems due to sperm competition. Whereas intensity of sperm competition is the significant predictor of testes sizes in other taxa such as mammals, frogs, birds, insects, and fish, in salamanders the intensity of male-male competition in the transfer of spermatophores to females is predicted to be a critical factor. This is because males have to deposit more spermatophores to secure reproductive pay-off under higher intensity of male-male competition. I hypothesized that salamander species that breed explosively as groups …

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Quantitative Reconstruction And Two-Dimensional, Steady Flow Hydrodynamics Of The Plesiosaur Flipper, Mark Cruz Deblois Jan 2013

Quantitative Reconstruction And Two-Dimensional, Steady Flow Hydrodynamics Of The Plesiosaur Flipper, Mark Cruz Deblois

Theses, Dissertations and Capstones

Plesiosaurs are a group of extinct marine reptiles that thrived during the Mesozoic Era. They are unique for swimming with two hydrofoil-shaped flippers. Penguins, sea turtles, and cetaceans all have hydrofoil shaped flippers but penguins and sea turtles only use the front pair to produce thrust and cetaceans use their tail flukes. Consequently, the mode of swimming for plesiosaurs has long been debated. However, a quantitative study of the hydrodynamic properties of the flippers, which would constrain inference about their mode of swimming, has not yet been done. The main reason is that the trailing edge of the plesiosaur flipper …

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Dietary Preference Of The Queensnake (Regina Septemvittata), Timothy J. Brust Jan 2013

Dietary Preference Of The Queensnake (Regina Septemvittata), Timothy J. Brust

Theses, Dissertations and Capstones

The Queensnake (Regina septemvittata) is a small secretive water snake found throughout the eastern United States. Once common, their numbers have declined to the extent that they are now threatened throughout most of their range, largely the result of pollutant-based reduction in prey species. These snakes are assumed to eat molted crayfish exclusively. For some common crayfish species, molting happens only twice a summer during a two- week period. It has not been documented if Queensnakes eat anything besides crayfish on a regular basis. The purpose of this study was to determine the prey preference of Queensnakes with particular focus …

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Evaluating The Utility Of Beaver Reintroduction Programs For Enhancing Habitat For Rainbow Trout And Steelhead, Jonathan Rodger Hegna Jan 2013

Evaluating The Utility Of Beaver Reintroduction Programs For Enhancing Habitat For Rainbow Trout And Steelhead, Jonathan Rodger Hegna

All Master's Theses

Beaver reintroduction programs are increasingly being viewed as a way to enhance salmonid habitat and production. However, the actual effectiveness of using beavers as a habitat enhancement tool for ESA listed steelhead Oncorhynchus mykiss populations is unknown. We examined the type of habitat, at both the microhabitat and mesohabitat levels, preferred by steelhead in three small streams in the upper Yakima Basin, WA through standard snorkel surveys and habitat measurements. Our results suggest that steelhead in small streams strongly prefer (relative to availability) microhabitats that have deeper water(> 30 cm), slow stream velocities(< 0 .05 mis), and complex cover types. Habitat partitioning among the size-classes (small< 50 mm, medium 50-90 mm, large> 90 mm total length, TL) principally operated …

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Short-Term Responses Of Fish Assemblages To Habitat Restoration In A Small Midwestern Stream, John Leon West Jan 2013

Short-Term Responses Of Fish Assemblages To Habitat Restoration In A Small Midwestern Stream, John Leon West

Masters Theses

Recent efforts to restore stream habitat have become a common practice, yet evaluations of biotic responses to these practices are not as common. I evaluated fish assemblage response to restoration in a reach of Kickapoo Creek, a fourth order stream southwest of Charleston, Illinois. Restoration included 446 meters of bank stabilization, pool scouring keys, and the creation of two artificial riffles. To have a representation of pre-restoration fish assemblages, I sampled four stream reaches of Kickapoo Creek twice before construction of habitat restoration: two control reaches (upstream and downstream) and two restored reaches within a 0.5 km restoration stretch (upstream …

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