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Full-Text Articles in Physical Sciences and Mathematics

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver Aug 2017

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver

Electronic Theses and Dissertations

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase.

Historically, …


Late Quaternary Dragon Lizards (Agamidae: Squamata) From Western Australia, Julie Rej May 2017

Late Quaternary Dragon Lizards (Agamidae: Squamata) From Western Australia, Julie Rej

Electronic Theses and Dissertations

Fossil Agamidae from Western Australia have been the subject of limited study. To aid in fossil agamid identification, Hocknull (2002) examined the maxilla and dentary of several extant species from Australia and determined diagnostic characters for various species groups. In the study here, fossil agamids from two localities in Western Australia, Hastings Cave and Horseshoe Cave, were examined, grouped, and identified to the lowest unambiguous taxonomic level. Morphometric analyses were conducted to compare morphotypes, and find additional diagnostic characters. From Hastings Cave there were two maxilla morphotypes and three dentary morphotypes. Based on identifications, taxa present at this locality were …


Improving Survey Methodology To Monitor Rare Grassland Birds In South Dakota, Kassondra Hendricks Jan 2017

Improving Survey Methodology To Monitor Rare Grassland Birds In South Dakota, Kassondra Hendricks

Electronic Theses and Dissertations

Breeding Bird Survey (BBS) data for grassland bird species has shown the most rapid population decline of any other bird group. Current roadside survey techniques, however, may fall short of providing accurate numbers of rare grassland bird species such as chestnut-collared longspur (Calcarius ornatus), lark bunting (Calamospiza melanocorys), Sprague’s pipit (Anthus spragueii), and Baird’s sparrow (Ammodramus bairdii). Trends resulting from roadside data for grassland birds are oftentimes determined to be statistically insignificant because many grassland bird species occur on too few routes, occur in low numbers per route, and show high annual fluctuations in number. It is possible roadside surveys …


Evaluation Of The Deadwood Bighorn Sheep Herd Translocation, Ty J. Werdel Jan 2017

Evaluation Of The Deadwood Bighorn Sheep Herd Translocation, Ty J. Werdel

Electronic Theses and Dissertations

From 2015-2017, we evaluated a newly established bighorn sheep (Ovis canadensis) herd in the Deadwood Region of the Black Hills, South Dakota. Our objectives were to 1a) determine annual survival rates, 1b) determine cause-specific mortality, 1c) estimate population size, 2a) assess genetic diversity, 2b) assess disease prevalence, 3) evaluate movement patterns post-release, 4a) evaluate 3rd-order habitat selection, and 4b) estimate herbaceous biomass at foraging sites post-release of translocated bighorn sheep. In February 2015, we captured and translocated 26 bighorn sheep from the Luscar Mine near Hinton, Alberta, Canada to the Deadwood Region of the Black Hills, South Dakota. Overall annual …


An Evaluation Of Nitrogen Supplementation And Processed Soy Fractions On The Performance Of Cultured Fishes, Brandon M. White Jan 2017

An Evaluation Of Nitrogen Supplementation And Processed Soy Fractions On The Performance Of Cultured Fishes, Brandon M. White

Electronic Theses and Dissertations

World population growth has resulted in an increased demand for a sustainable food supply. This rapid growth coupled with an increased per capita consumption of seafood, has resulted in many of the world’s marine fisheries being over-exploited in an effort to meet the global demand for seafood. Aquaculture has attempted to fill the supply and demand gap created by the dwindling supply of fish in the world’s oceans. Fishmeal (FM) has traditionally been the primary protein ingredient in aquafeeds fed to farm-raised fish, however its unstable supply and increasing price have driven researchers to identify alternative protein sources. Soybean meal …


Mountain Lion (Puma Concolor) Population Characteristics And Resource Selection In The North Dakota Badlands, Randy D. Johnson Jan 2017

Mountain Lion (Puma Concolor) Population Characteristics And Resource Selection In The North Dakota Badlands, Randy D. Johnson

Electronic Theses and Dissertations

Mountain lions (Puma concolor) have significant ecological impacts on the ecosystems they inhabit, leading to both biological and social ramifications. Yet, due to the relatively recent natural recolonization by mountain lions of the Little Missouri Badlands Region of western North Dakota, detailed data regarding many aspects of this population have been lacking. Therefore, we studied mountain lions occupying the Badlands Region to improve our understanding of mountain lion population ecology, resource selection, and occurrence in North Dakota. Our objectives were to: 1) improve the accuracy of home range size, subadult movement, and survival estimates of mountain lions in …


Measuring Aquatic Organism Responses To Grassland Restoration: Does The Field Of Dreams Really Exist?, David A. Schumann Jan 2017

Measuring Aquatic Organism Responses To Grassland Restoration: Does The Field Of Dreams Really Exist?, David A. Schumann

Electronic Theses and Dissertations

Landscape homogenization and the degradation of riparian areas has greatly impaired stream ecosystems throughout North America. Conservation programs may repair riparian ecosystems to indirectly improve water quality and instream habitat heterogeneity in hopes to elicit biological responses. However, focused manipulations on isolated stream fragments have rarely achieved biological goals. Prairie streams with restored riparian areas were appraised (chemical, physical, and biological variables) to quantify the indirect effects of prevalent grassland conservation practices on aquatic resources. Riparian rehabilitation, via passive methods, promoted bank-stabilizing vegetation along all conservation stream reaches. Riparian vegetation and function quickly recovered from previous agricultural disturbances at conservation …