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Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2010, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman, Raghavendra Kurada 2011 Old Dominion University

Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2010, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman, Raghavendra Kurada

Status and Trends for Virginia Chesapeake Bay

The period prior to the implementation of the Chesapeake Bay Monitoring Program was characterized by a marked decline in the water quality of the Chesapeake Bay. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality (e.g. USEPA, 1982,1983;Officer et al.,1984; Orth and Moore, 1984). The results of concentrated research efforts in the late 1970s and early 1980s stimulated the …


Preliminary Evaluations Of Secondary Productivity Estimates As Indicators Of The Ecological Value Of The Benthos To Higher Trophic Levels In Chesapeake Bay, Daniel M. Dauer, Michael F. Lane, Roberto J. Llansó, Robert Diaz 2011 Old Dominion University

Preliminary Evaluations Of Secondary Productivity Estimates As Indicators Of The Ecological Value Of The Benthos To Higher Trophic Levels In Chesapeake Bay, Daniel M. Dauer, Michael F. Lane, Roberto J. Llansó, Robert Diaz

Benthic Applications

The primary objective of this project was to develop an analytical tool that management could use to assess the ecological value of the benthos for higher trophic levels. Ideally any tool developed should be simple to implement, adaptable to both fixed and probability monitoring programs and applicable across multiple spatial and temporal scales. Direct evaluations of secondary productivity involve time-consuming cohort or size-based methods that require multiple measurements of the populations in question over time (Dolbeth et al., 2005; Cusson and Bourget, 2005). However, empirical regression models have been developed that provide reasonable alternatives to these techniques when direct measurements …


Synopsis Of Methods Used To Map Historical Vegetation In Oregon And Washington, Based On General Land Office Survey Notes, John Christy, Edward Alverson 2011 Portland State University

Synopsis Of Methods Used To Map Historical Vegetation In Oregon And Washington, Based On General Land Office Survey Notes, John Christy, Edward Alverson

Institute for Natural Resources Publications

Mapping historical vegetation in Oregon and Washington has been ongoing since about 1993. It is based primarily on General Land Office (GLO) surveyors' descriptions of vegetation, recorded between 1851 and about 1940. For areas along the coast and the lower Columbia River, topographic maps ("T-sheets") of the U.S. Coast Survey (later called U.S. Coast and Geodetic Survey, and more recently the National Geodetic Survey)—based on field work conducted between 1852 and 1889—have been integrated whenever possible with GLO data because of their superior cartography and land cover symbology. For more detailed descriptions of mapping methods, see Christy and Alverson (2011) …


Brody-Bertalanffy Growth Curves From Tag And Recapture Studies On Cabezon (Scorpaenichthys Marmoratus) And Gopher Rockfish (Sebastes Carnatus) Of The Central Coast, Christie Yorke 2011 California Polytechnic State University, San Luis Obispo

Brody-Bertalanffy Growth Curves From Tag And Recapture Studies On Cabezon (Scorpaenichthys Marmoratus) And Gopher Rockfish (Sebastes Carnatus) Of The Central Coast, Christie Yorke

Biological Sciences

No abstract provided.


Movement Ecology Of An Intercontinental Migratory Bird During Spring Stopover, Emily Beth Cohen 2011 University of Southern Mississippi

Movement Ecology Of An Intercontinental Migratory Bird During Spring Stopover, Emily Beth Cohen

Dissertations

Movement ecology is a component of nearly all aspects of animal behavior and an animal’s decision to move is likely influenced by a complex combination of exogenous and endogenous factors. Therefore, an examination of the causes and consequences of organismal movement provides a conceptual framework for understanding complex behavioral strategies. My dissertation research is focused on the movement ecology of an intercontinental migratory songbird during spring migration. I adopted experimental approaches to study the factors influencing how a songbird migrant, red-eyed vireos (Vireo olivaceus), makes decisions in unfamiliar landscapes from the initiation of spring stopover.

I simulated the …


Homoploid Hybrid Speciation In A Rare Endemic Castilleja From Idaho (Castilleja Christii, Orobanchaceae), Danielle Leigh Clay 2011 Boise State University

Homoploid Hybrid Speciation In A Rare Endemic Castilleja From Idaho (Castilleja Christii, Orobanchaceae), Danielle Leigh Clay

Boise State University Theses and Dissertations

Evidence to support the origins of a putative hybrid species with certainty must be determined using several lines of evidence: the presence of genetic additivity of parental marker alleles in a putative hybrid species, along with ecological or niche separation. Novel or transgressive morphological traits obtained through chromosomal rearrangements during hybridization may facilitate niche separation of the hybrid species from progenitor habitats. These evolutionary processes together enforce reproductive isolation and promote an independent evolutionary trajectory in hybrid species. By studying these evolutionary processes in putative hybrid species, researchers may identify hybrid species with confidence.

We employed multiple lines of evidence …


Review Of Sandhill And Whooping Cranes: Ancient Voices Over America's Wetlands By Paul Johnsgard, Jane E. Austin 2011 United States Geological Survey, Northern Prairie WRC

Review Of Sandhill And Whooping Cranes: Ancient Voices Over America's Wetlands By Paul Johnsgard, Jane E. Austin

The Prairie Naturalist

Paul Johnsgard has long been captivated by wild cranes and their unique vocalizations, courtship dances, and wide-ranging migrations. As a scientist and an admirer, Johnsgard has watched their migrations and behaviors for decades as hundreds of thousands of cranes staged each spring by the central Platte River, not far from his home in Lincoln, Nebraska. As an artist, he has skillfully captured their courtship dances and other behaviors in his exceptional line drawings. And, as an author, he has written extensively on their ecology in three earlier books: Cranes of the World (1983), Those of the Gray Wind: The Sandhill …


Book Review: Effects Of Climate Change On Birds, Edited By Anders Pape Meller, Wolfgang Fiedler, And Peter Berthold, Brian J. Olsen 2011 University of Maine

Book Review: Effects Of Climate Change On Birds, Edited By Anders Pape Meller, Wolfgang Fiedler, And Peter Berthold, Brian J. Olsen

The Prairie Naturalist

Book review of Effects of Climate Change on Birds, edited by Anders Pape Meller, Wolfgang Fiedler, and Peter Berthold.

Climate scientists from across the globe predict vast changes during the next century in the planet's temperatures, precipitation, storm intensities, fire regimes, hydrologic cycles, and atmospheric, water, and soil chemistries. The changes will be global, but their effects will be felt locally everywhere. To find a scientifically and socially engaging bellwether of these events, we need to look only through the lens of avian biology. Birds are found from pole to pole; their movements connect continents. They are loud, colorful …


Effects Of Tannin-Containing Feed On Haemonchous Contortus In Sheep And Its Behavioral Implications, Jessica A. Juhnke 2011 Utah State University

Effects Of Tannin-Containing Feed On Haemonchous Contortus In Sheep And Its Behavioral Implications, Jessica A. Juhnke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Herbivores prefer foods that supply required nutrients and avoid those with excess nutrients and plant secondary compounds (PSC). Nevertheless, PSC such as condensed tannins can provide beneficial medicinal effects to herbivores. The objectives of this study were to determine: 1) if parasitized lambs increased preference for a tannin-rich food after they experienced the beneficial antiparasitic effects of tannins relative to parasitized lambs that did not experience such benefits, 2) if preference for the tannin-containing food in the former group decreased when parasite burdens subsided, and 3) if the tannin-enriched food decreased parasitic burdens.

Twenty-two lambs were familiarized with beet pulp …


Have Introduced Brown Trout (Salmo Trutta) Affected Native Aquatic Vertebrates In Western United States Streams?, Nora K. Burbank 2011 Utah State University

Have Introduced Brown Trout (Salmo Trutta) Affected Native Aquatic Vertebrates In Western United States Streams?, Nora K. Burbank

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The introduction of exotic species to areas outside of their native range is one of the greatest threats to the biodiversity of native freshwater organisms. Exotic species have outcompeted native species for resources such as food and shelter, and in some cases these interactions have resulted in local extinctions or reductions in abundance of those native species. Brown trout are native to Eurasia, but have been introduced to much of the rest of the world, including the United States. In some parts of their introduced range, brown trout have substantially reduced the abundance and home ranges of some native fish …


Isotopic Tracer Reveals Depth-Specific Water Use Patterns Between Two Adjacent Native And Non-Native Plant Communities, Clémence Pascale Warren 2011 Utah State University

Isotopic Tracer Reveals Depth-Specific Water Use Patterns Between Two Adjacent Native And Non-Native Plant Communities, Clémence Pascale Warren

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Non-native plants have invaded over 100 millions of acres of western arid land in the US and dramatically altered nutrient cycling rates. Changes in water cycling caused by invasive species are of particular interest because primary production in the Western US is typically limited by water availability and aquifer recharge reflects plant demand. Large-scale invasions can, therefore, be expected to cause large-scale changes in hydrological cycles, but until recently, there have been considerable limitations in the ability to measure the timing, location, and extent of water use. Here we injected a tracer, deuterated water (D2O), into five soil …


An Assessment Of Vegetation Metrics And Plot Types To Measure Seasonal Variation And Grazing Effects On Riparian Plant Communities, Caroline M. Laine 2011 Utah State University

An Assessment Of Vegetation Metrics And Plot Types To Measure Seasonal Variation And Grazing Effects On Riparian Plant Communities, Caroline M. Laine

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring changes in vegetation is important on public lands. Observing how plant communities respond to changes in land management can give insightful information about which management practices are sustainable. Because water is scarce in the western United States, many land managers focus their monitoring efforts along streams. However, monitoring streamside vegetation is challenging due to a variety of factors and can be confounded by factors such as seasonal climate variation and management activities, like cattle grazing.

In vegetation assessment, there are a variety of measurements that are taken to glean valuable information. Some attributes of interest include how much vegetation …


Using Species Distribution Models To Assess Invasion Theory And Provide Management Recommendations For Riparian Areas In The Eastern Columbia And Western Missouri River Basins, Diane R. Menuz 2011 Utah State University

Using Species Distribution Models To Assess Invasion Theory And Provide Management Recommendations For Riparian Areas In The Eastern Columbia And Western Missouri River Basins, Diane R. Menuz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Globalization has created opportunities for plant and animal species to be transported to novel ecosystems. A subset of these species become invasive species, which are able to persist and spread rapidly to become influential components in their new ecosystems. Invasive species are often able to out-compete co-occurring native species and can alter fundamental ecosystem properties, such as soil nutrient availability or time between wildfires in a region. The United States is estimated to lose $34 billion per year to invasive plant species through costs to control unwanted species and lowered crop and forage production.

We used statistical models to better …


A Landscape Approach To Late Prehistoric Settlement And Subsistence Patterns In The Mojave Sink, Tiffany Ann Thomas 2011 University of Nevada, Las Vegas

A Landscape Approach To Late Prehistoric Settlement And Subsistence Patterns In The Mojave Sink, Tiffany Ann Thomas

UNLV Theses, Dissertations, Professional Papers, and Capstones

The environment of the Late Prehistoric period (1200 A.D. to Historic Contact) Mojave Sink was wetter than modern conditions. The settlement and subsistence patterns of the occupants of the region during this period were driven by the availability of water, subsistence resources, raw material sources, and tradition. These people utilized the regional landscape based upon the seasonal availability of these resources. Supplemental agricultural production has been proposed for the Mojave River Delta due to the more favorable environmental conditions of this period. If agriculture was being practiced it would have affected the regional land-use patterns. For this thesis I propose …


Bycatch Of The Lake Pontchartrain Basin Inshore Shrimp Fishery And Its Effect On Two Sea Catfish Species: The Gafftopsail Catfish (Bagre Marinus) And The Hardhead Catfish (Ariopsis Felis), Scott P. Eustis 2011 University of New Orleans Department of Earth and Environmental Sciences

Bycatch Of The Lake Pontchartrain Basin Inshore Shrimp Fishery And Its Effect On Two Sea Catfish Species: The Gafftopsail Catfish (Bagre Marinus) And The Hardhead Catfish (Ariopsis Felis), Scott P. Eustis

LSU New Orleans Theses and Dissertations

In Lake Pontchartrain Basin, commercial fishing in estuarine habitats impacts many non-target species collected as bycatch. I investigated the bycatch assemblages collected by commercial vessels and compared these to assemblages collected by typical fishery-independent methods. I compared assemblages using analysis of similarity (ANOSIM) and determined important species by weight and abundance using similarity percentages analyses (SIMPER). I also examined differences in size-class distributions by gear type using density kernel plots and Mann-Whitney U tests. The two gear types collected significantly different assemblages (ANOSIM R = 0.522, p = 0.001) and gear type explained more composition differences than other factors such …


Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda 2011 University of Nevada, Las Vegas

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …


Microbial Impacts On Endocrine Disrupting Contaminants: Las Vegas Wash And Lake Mead, Nevada, Susanna May Blunt 2011 University of Nevada, Las Vegas

Microbial Impacts On Endocrine Disrupting Contaminants: Las Vegas Wash And Lake Mead, Nevada, Susanna May Blunt

UNLV Theses, Dissertations, Professional Papers, and Capstones

International concern over endocrine disrupting chemicals (EDCs) has become heightened in recent years as more studies reveal their persistence in the environment and their detrimental effects on wildlife. However, little is known about the role of microorganisms in the fate and transport of these compounds in surface waters. Las Vegas Wash, a stream flowing into Lake Mead and fed primarily by treated wastewater effluent, provided a unique experimental system in which to study the role microorganisms play in the dispersal of these compounds in aquatic systems. Samples were collected from the Las Vegas Wash downstream of the Las Vegas Valley's …


Effect Of Diet Quantity And Quality On Female Sampling Behavior And Mating Preferences In A Field Cricket, Heidi L. Bulfer 2011 University of Nebraska-Lincoln

Effect Of Diet Quantity And Quality On Female Sampling Behavior And Mating Preferences In A Field Cricket, Heidi L. Bulfer

School of Biological Sciences: Dissertations, Theses, and Student Research

Understanding the adaptive significance of variation in female mating behaviour is important because variation may often be favored by selection instead of a change in mean mating behaviour, particularly in variable environments. Females are known to adjust their mating behaviour to a variety of intrinsic and extrinsic factors including nutrition. There are multiple reasons why female behaviours might vary with nutrition; we tested two of these hypotheses: the search cost hypothesis and the direct benefits hypothesis. These hypotheses are not mutually exclusive, but they make contrasting predictions under some conditions. Low nutrition females may have less available energy to support …


Life History Tradeoffs And Phenotypic Plasticity: The Tale Of A Flight Polyphenic Field Cricket, Chandreyee Mitra 2011 University of Nebraska-Lincoln

Life History Tradeoffs And Phenotypic Plasticity: The Tale Of A Flight Polyphenic Field Cricket, Chandreyee Mitra

School of Biological Sciences: Dissertations, Theses, and Student Research

Most organisms are resource limited. Such limitations can result in tradeoffs between life history traits -- any traits that affect survival or reproduction. Flight polyphenic field crickets are thought to be a classic example of such a life history tradeoff, in which individuals tradeoff investment in flight capability and investment in reproduction. This polyphenism results from the interaction of two morphological traits: wing morphology (short or long) and flight muscle morphology (functional pink or non-functional white), and is affected by both genes and the environment. I examined life history traits of a flight polyphenic field cricket, Gryllus lineaticeps. First, …


Review Of Teaching Children Science: Hands-On Nature Study In North America, 1890-1930 By Sally Kohlstedt, Meena M. Balgopal 2011 Colorado State University - Fort Collins

Review Of Teaching Children Science: Hands-On Nature Study In North America, 1890-1930 By Sally Kohlstedt, Meena M. Balgopal

The Prairie Naturalist

Many scientists and educators agree that the goal of science education is to prepare students "to know, use and interpret scientific explanations of the natural world," as cited in the National Research Council publication, Taking Science to School: Learning and Teaching Science in Grades K-8 (DuschI et al. 2007). Yet, many science instructors of K-12 and post-secondary students often rely on teacher-telling modes of pedagogy and neglect to engage their students in natural inquiry and scientific study that model the research methods used by scientists. As a result, many young people are not aware of how scientists make discoveries about …


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