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Conservation And Ecology Of The Yellow-Blotched Sawback (Graptemys Flavmaculata), William Winsyl Selman Ii

Dissertations

The role of species conservation is becoming increasingly important due to the mounting pressures from humans on habitats and populations of organisms. This is particularly evident in riverine ecosystems throughout the world where the human demand for freshwater resources is increasing, and consequently, the number of imperiled aquatic organisms is also growing. The seven chapters of this dissertation primarily focus on the Yellow-blotched Sawback, Graptemys flavimaculata, an endangered riverine turtle that is endemic to the Pascagoula River system of southeast Mississippi, USA. At the population level, we aimed to study the impacts of Hurricane Katrina on two study populations within …

Un Estudio Ecológico De Las Lagartijas Del Valle Seco De Buenavista Y De Los Valles Húmedos De La Josefina Y Salango, Ross Brennan

Independent Study Project (ISP) Collection

La región costera del sur de la provincia de Manabí, Ecuador es un lugar de gran biodiversidad y endemismo. En esta zona el desierto peruano del Tumbes y el bosque húmedo del Chocó se encuentran. La gran cantidad de especies endémicas y la alta biodiversidad resultan de la interacción entre las dos regiones y la diversidad de hábitats que crean. Hay bosques secos tropicales y bosques húmedos muy cerca de Puerto López. Sin embargo, esta región está cambiando rápidamente debido a las actividades humanas; hay progresiva desertificación y otras amenazas a la diversidad. Además, no hay muchos estudios de la …

Interisland Variability Of Dune Plant Community Structure On Virginia's Barrier Islands, Justin K. Shafer

Biological Sciences Theses & Dissertations

The barrier islands of the Virginia Coast Reserve LTER site provide an opportunity to study interisland variability of dune plant communities. My research focused on the variation in biomass and diversity of communities among islands and dune positions. Grassy dunes of young, intermediate and old age were sampled on Smith, Hog, and Parramore Islands. Aboveground biomass was obtained from harvest plots, and roots were extracted from cores. Data were collected on depth to groundwater and total soil nitrogen. Variation in mean aboveground biomass was evident among the islands with the highest values on Hog Island, followed by Smith, then Parramore …

What Is The Taxonomic Identity Of Minnesota Wolves?, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The taxonomic identity of the historical and current wolf (Canis lupus L., 1758 or Canis lycaon Schreber, 1775 or their hybrids) population in Minnesota (MN) and the Great Lakes region has been, and continues to be, controversial. So too does its legal status under the U.S. Endangered Species Act. This review summarizes the morphological and genetic information about that population and concludes that historically the MN population consisted of a gray wolf (C. lupus) in the west and an eastern type (Canis lupus lycaon or C. lycaon) in the east with intergrades or hybrids between …

Fall 2010, Nsu Oceanographic Center

Currents

No abstract provided.

Behavior And Habitat Use Of Greater Sandhill Cranes Wintering In East Tennessee, David A. Aborn

Proceedings of the North American Crane Workshop

An increase of eastern greater sandhill cranes (Grus canadensis tabida) stopping over and wintering at the Hiwassee Wildlife Refuge in east Tennessee has led to overcrowding at the refuge, resulting in crane use of private property. Proper management is needed to prevent the cranes from becoming a nuisance, increase the suitability of the refuge for waterfowl, and reduce the likelihood of a disease outbreak. Observations of cranes revealed that cranes spent 83% of their time foraging, alert, or preening. Sandhill cranes foraged primarily in agricultural and grassy fields, whereas mudflats and shallow water were used for preening and …

Population Status And Geographic Distribution Of Greater Sandhill Cranes In The Mid-Continent Population, Gary L. Krapu, David A. Brandt

Proceedings of the North American Crane Workshop

Number and geographic distribution of greater sandhill cranes (Grus canadensis tabida) in the mid-continent population (MCP) of sandhill cranes were evaluated. G. c. tabida comprised 7 of 133 (5.3%) individuals of 3 subspecies which projects to 31,579 ± 11,661 (SE) individuals in an estimated spring MCP of 600,000 cranes. From a platform transmitting terminal (PTT)-marked sample representative of the geographic distribution of G. c. tabida, 10 of 13 (77%) settled during the breeding season in east-central Canada/Minnesota, including 4 in northwestern Minnesota, 4 in Manitoba (2 at sites near the Minnesota border), and 2 in Ontario. Three …

Countability Of Sandhill Cranes In Aerial Surveys, Douglas H. Johnson, John W. Solberg, Courtney L. Amundson

Proceedings of the North American Crane Workshop

Aerial surveys are used to monitor populations of many wildlife species, including sandhill cranes (Grus canadensis). In addition to the usual problems of detectability (involving both availability and perceptibility), aerial surveys of concentrated animals are subject to countability issues; from a rapidly moving aircraft, observers cannot count or accurately estimate the number of animals in a large group. Calibration is sometimes performed in an effort to adjust aerial counts for incomplete detectability and countability by calculating the ratio of animals actually in a group to the number in the group estimated from the aircraft. Here we explore alternative, …

Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species are widely recognized as a major threat to biodiversity and ecosystem stability. Wetland ecosystems tend to be much more susceptible to invasions because of their location on the landscape where water, nutrients, and the impacts of disturbances accumulate. Invasive plants have the ability to alter ecosystem processes and community/population dynamics. The ability of invasive plants to alter these processes can have profound economic consequences. In the United States, control of invasive wetland species alone costs approximately 155 million dollars annually. The state of Nebraska spends 2 million dollars annually controlling invasive plant species in the Platte River …

The Ratio Of Gametophytes To Tetrasporophytes Of Intertidal Chondrus Crispus (Gigartinaceae) Across A Salinity Gradient, Michele Guidone, Sean Grace

Biology Faculty Publications

Population studies of the Gigartinaceae (Rhodophyta) have often observed that the ratio of gametophytes to tetrasporophytes varies with the location of the population or the time of sampling. For some species, patterns have emerged that correlate this ratio to one or a few particular environmental variables, such as elevation, wave exposure, or season. Identifying these distributional patterns is an important step towards understanding what (if any) ecological differences exist between the two free-living life history stages.

The purpose of this study was to measure the ratio of gametophytes to tetrasporophytes of intertidal populations of Chondrus crispus across a decreasing salinity …

Trophic Implications Of Light Reductions For Amphibolis Griffithii Seagrass Fauna, Adam Gartner

Theses: Doctorates and Masters

The ongoing threat of seagrass loss from reduced light availability, coupled with our lack of knowledge of associated trophic responses has motivated this characterization of the flow-on effects of light reductions to Amphibolis griffithii seagrass fauna. Recently, field manipulations of varying light reductions, induced disturbances in a A. griffithii seagrass meadow that have been shown to effect potential food resources and the structural complexity of seagrass habitats for macroinvertebrates. This offered the opportunity to assess the flow-on effects to seagrass for fauna, a topic that has seldom been examined. This study investigated the effects of different light reduction intensity (high: …

Temporal Shifts In Demography And Life History Of An Anadromous Alewife Population In Connecticut, Justin P. Davis, Eric T. Schultz

EEB Articles

Populations of anadromous alewives (Alosa pseudoharengus) are declining throughout much of their range, particularly in southern New England where fishery moratoriums have recently been instituted in three states. The alewife run at Bride Brook, a coastal stream in East Lyme, Connecticut, was studied from 2003-06 to assess shifts in demography and life history. Annual censuses of abundance, along with sampling for size, age, and spawning history structure were conducted. These data were compared to similar data in 1966-67 at this site. Recent alewife runs at Bride Brook featured lower abundance and younger, smaller fish that were less likely to be …

A Comparative Ecological Study Of Two Sister Species Of Darters In Kentucky, Etheostoma Kantuckeense And Etheostoma Lawrencei, Bjorn Victor Schmidt

Masters Theses & Specialist Projects

Etheostoma kantuckeense and E. lawrencei are former members of the wide ranging E. spectabile species complex. Etheostoma kantuckeense is endemic to the Barren River Basin in Southern Kentucky and Northern Tennessee, while E. lawrencei occurs in the Green River, Salt River, and Cumberland River Basins of Central and Eastern Kentucky. Isolation of populations within these drainages has allowed for a relatively recent evolutionary divergence, leading to slight differences in morphology. This study was conducted to address if geographical isolation has led to measurable differences in the ecology of these two species. In particular, habitat preference across three spatial scales and …

Miti Iko Wapi Ii ?, Taylor Tully

Independent Study Project (ISP) Collection

Vegetative communities within the savannah ecosystem oscillate between grassland and woodland states. Research has found that ecological perturbations resulting from elephants, fire, other herbivores and humans have a significant influence on the oscillation of vegetative communities. Understanding these forces and how they interplay to influence vegetative dynamics states is essential to a developing any effective conservation management program. A previous study, in 2003, was conducted to establish baseline data on vegetative community structure, elephant damage and fire damage within Ndarakwai Ranch. (Hamilton and Downing 2003). However, the study drew few definitive conclusions and suggested further research. This study was a …

Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann

All Theses And Dissertations

Populations of the gastropod Nucella lapillus are polymorphic for shell color, with light-colored shells predominating on warmer, wave-protected shores and dark-colored shells limited primarily to cooler, wave-exposed shores. During thermal stress, darker shells attain higher body temperatures than lighter shells. These results suggest that heat stress may determine field distribution patterns. However, there is currently little evidence of physiological consequences of thermal stress in these organisms. Following the guiding hypothesis that heat stress leads to cellular energy depletion, we explored whether the central energy regulator AMP-activated Protein Kinase (AMPK) is activated by heat stress. We compared this response in both …

Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun

EEB Articles

Populations of anadromous alewife Alosa pseudoharengus and blueback herring Alosa aestivalis, collectively referred to as river herring, have declined in the Connecticut River. A hypothesis for why river herring have declined is that predation pressures have increased associated with recent increases in abundance of striped bass Morone saxatilis. Information on striped bass abundance, size structure, and consumption rates are required to test this hypothesis. This study was designed to provide estimates of striped bass population size in the Connecticut River during the spring migration season, via an intensive mark-recapture exercise and either an open or robust mark-recapture model. …

Altered Ecological Flows Blur Boundaries In Urbanizing Watersheds, Todd R. Lookingbill, Sujay S. Kaushal, Andrew J. Elmore, Robert Gardner, Keith N. Eshleman, Robert H. Hilderbrand, Raymond P. Morgan, Walter R. Boynton, Margaret A. Palmer, William C. Dennison

Geography and the Environment Faculty Publications

The relevance of the boundary concept to ecological processes has been recently questioned. Humans in the post-industrial era have created novel lateral transport fluxes that have not been sufficiently considered in watershed studies. We describe patterns of land-use change within the Potomac River basin and demonstrate how these changes have blurred traditional ecosystem boundaries by increasing the movement of people, materials, and energy into and within the basin. We argue that this expansion of ecological commerce requires new science, monitoring, and management strategies focused on large rivers and suggest that traditional geopolitical and economic boundaries for environmental decision making be …

Factors Influencing Predation On Juvenile Ungulates And Natural Selection Implications, S. M. Barber-Meyer, L. D. Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Juvenile ungulates are generally more vulnerable to predation than are adult ungulates other than senescent individuals, not only because of their relative youth, fragility, and inexperience, but also because of congenital factors. Linnell et al.’s (Wildl. Biol. 1: 209-223) extensive review of predation on juvenile ungulates concluded that research was needed to determine the predisposition of these juveniles to predation. Since then, various characteristics that potentially predispose juvenile ungulates have emerged including blood characteristics, morphometric and other condition factors, and other factors such as birth period, the mother’s experience, and spatial and habitat aspects. To the extent that any of …

Management Of Lands Along The Platte River From Elm Creek To Lexington, Nebraska, As Crane Habitat, James J. Jenniges, Mark M. Peyton

Proceedings of the North American Crane Workshop

To meet Federal Energy Regulatory Commission (FERC) license requirements for the operation of 5 hydroelectric power plants on the North Platte and Platte Rivers in Nebraska, the Nebraska Public Power District (NPPD) and The Central Nebraska Public Power and Irrigation District (Central) together have become the second largest owners and managers of lands for the conservation of endangered species and migratory waterbirds along the central reach of the Platte River. We describe here the management activities on the properties, success of the management in achieving objectives, and the response of sandhill (Grus canadensis) and whooping cranes (G. …

Salt Marshes As A Source Of Chromophoric Dissolved Organic Matter (Cdom) To Southern California Coastal Waters, Catherine D. Clark, Liannea P. Litz, Stanley B. Grant

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

To determine chromophoric dissolved organic matter (CDOM) sources in Southern California coastal waters, optical properties of a river outlet and adjacent tidally flushed salt marshes were monitored (dry season; June July 2001). Average absorption coefficients doubled at ebb vs. flood tides (4.8 +/- 1.5 vs. 2.1 +/- 0.9 m(-1); 300 nm), suggesting significant salt marsh CDOM inputs into coastal waters. Average spectral slopes were not statistically different for any sites or tides (0.010 +/- 0.002 nm(-1)), consistent with salt marsh CDOM dominating coastal waters. Three-dimensional fluorescence excitation-emission matrices (EEMs) at ebb tide showed contributions from terrestrial, protein, and marine humic-like …

Waterhole Dynamics And Chemical Signals Of African Elephants ( Loxodonta Africana ), Stacie Marie Castelda

College of Graduate Studies: Theses & Dissertations

The distribution of mammals in a savanna environment is influenced by abiotic and biotic factors. The African savanna experiences distinct wet and dry seasons. Species become spatially restricted around water resources during the dry season, resulting in increased intraspecies and interspecies resource-based aggregation. A dominate species, such as the African elephant (Loxodonta africana), may influence this aggregation. I examined the influence of wet and dry seasons and ambient temperature on the use of a waterhole by elephants as well as the co-occurrence of elephants and other mammals at the waterhole. Biodiversity scans (October 2004-June 2007) and were performed at a …

Wolf Body Mass Cline Across Minnesota Related To Taxonomy?, L. David Mech, William J. Paul

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Recent genetic studies suggest that in northern Minnesota two species of wolves (Canis lupus L., 1758 or western wolf and Canis lycaon Schreber, 1775 (= Canis rufus Audubon and Bachman, 1851) or eastern wolf) meet and hybridize. However, little morphological information is available about these two types of wolves in Minnesota. We analyzed the mass of 950 female wolves and 1006 males older than 1 year from across northern Minnesota and found that it increased from 26.30 ± 0.56 kg (mean ± SE) for females and 30.60 ± 0.72 kg for males in northeastern Minnesota to 30.01 ± 0.43 …

Determining Winter Flounder Spawning Sites In Two Connecticut Estuaries, Eric T. Schultz, Jose J. Pereira, Peter J. Auster

EEB Articles

Winter flounder (Pseudopleuronectes americanus) come inshore during the late winter and early spring to lay their eggs in shallow bays and estuaries along the coast. Unlike most fish eggs, which are buoyant, these eggs are demersal and sink to the seafloor. This makes them vulnerable to burial from various types of natural and human caused disturbances (e.g., storms, mobile fishing gear, maintenance dredging). Our objective was to map spawning areas in two harbors and search for generalities among these sites that would allow us to predict where winter flounder might spawn in other areas. This would allow managers to avoid …

Current Status Of The Khulan (Equus Hemionus) In The Trans-Altai Gobi, Enkhbileg Dulamtseren, Adiya Yadamjav, Dovchindorj Ganbold, Mijidorj Batmunkh

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Since 1975, 25 wildlife surveys have been conducted in the Trans-Altai Gobi. In this paper we summarize results from the last 11 surveys, conducted between October 2000 and April 2005, and discuss our findings together with results from previous surveys.

Semi-Wild Population Of Kulans In The Bukhara Breeding Centre And Their Co-Habitation With Przewalski’S Horses, Karim Bahloul, Olga B. Pereladova, Natalia V. Soldatova, Ekaterina V. Sidorenko, Antoine J. Sempere

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Asiatic wild asses and Przewalski's horses initially inhabited steppe, semi-desert and desert areas, but Przewalski's horses became extinct in the wild, and kulans are under threat of disappearance. The Bukhara Breeding Centre (Uzbekistan) was created in 1976 for conservation and reintroduction of wild ungulate species. In 1977-1978, five kulans (two males and three females) from Barsa-Kelmes Island on the Aral lake were introduced to the reserve. The group increased to 25-30 animals in 1995-1998, when five Przewalski's horses from Moscow and St. Petersburg zoos were introduced to the same territory. We analyzed the home ranges, preferred habitats and social interactions …

Pathways Of Anaerobic Carbon Cycling Across An Ombrotrophic–Minerotrophic Peatland Gradient, Jason K. Keller, Scott D. Bridgham

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Peatland soils represent globally significant stores of carbon, and understanding carbon cycling pathways in these ecosystems has important implications for global climate change. We measured aceticlastic and autotrophic methanogenesis, sulfate reduction, denitrification, and iron reduction in a bog, an intermediate fen, and a rich fen in the Upper Peninsula of Michigan for one growing season. In 3-d anaerobic incubations of slurried peat, denitrification and iron reduction were minor components of anaerobic carbon mineralization. Experiments using 14C-labeled methanogenic substrates showed that methanogenesis in these peatlands was primarily through the aceticlastic pathway, except early in the growing season in more ombrotrophic peatlands, …

Evaluating The Long-Term Metacommunity Dynamics Of Tree Hole Mosquitoes, Alicia M. Ellis, L. Philip Lounibos, Marcel Holyoak

Dartmouth Scholarship

Four different conceptual models of metacommunities have been proposed, termed “patch dynamics,” “species sorting,” “mass effect,” and “neutral.” These models simplify thinking about metacommunities and improve our understanding of the role of spatial dynamics both in structuring communities and in determining local and regional diversity. We tested whether mosquito communities inhabiting water-filled tree holes in southeastern Florida, USA, displayed any of the characteristics and dynamics predicted by the four models. The densities of the five most common species in 3–8 tree holes were monitored every two weeks during 1978–2003. We tested relationships between habitat variables and species densities, spatial synchrony, …

Anadromous Rainbow Smelt And Tomcod In Connecticut: Assessment Of Populations, Conservation Status, And Need For Restoration Plan, Heather A. Fried, Eric T. Schultz

EEB Articles

(beginning of rainbow smelt executive summary)

Evidence indicates that anadromous rainbow smelt (Osmerus mordax) populations in Connecticut and elsewhere in the northeast United States have severely declined. Several sampling programs have documented declines in Connecticut’s smelt populations over the last three decades (Marcy 1976a, Marcy 1976b, Millstone Environmental Laboratory 2005). Similar declines have also been documented in the Hudson River (ASA Analysis & Communication 2005) and in Massachusetts (personal communication, Brad Chase, MA Division of Marine Fisheries 2004). Recreational and commercial fisheries in the region for this species have virtually ceased (Blake and Smith 1984). The Connecticut Fish Advisory Committee …

Assessment Of Anadromous Alewife And Blueback Herring Populations In Connecticut Coastal Streams And Connecticut River Tributaries, Justin P. Davis, Eric T. Schultz

EEB Articles

Alewife (Alosa pseudoharengus) and blueback herring (A. aestivalis) occur in anadromous populations that have a largely overlapping distribution from Florida to Newfoundland (Loesch 1987). Anadromous populations of these species are commonly collectively referred to as “river herring”. Adults inhabit coastal shelf waters until sexual maturity is reached at age 3-5 (Neves 1981). Sexually mature individuals make spawning migrations, commonly referred to as “runs”, into freshwater systems during spring months (Loesch 1987). Spawners can survive and return to spawn in subsequent years (Mullen et al. 1986). Juveniles reside in freshwater for 3-7 months, at which time they undertake a gradual migration …

The Natural History And Thermal Ecology Of A Population Of Spotted Turtles (Clemmys Guttata) And Wood Turtles (Glyptemys Insculpta) In West Virginia, Ariana N. Breisch

Theses, Dissertations and Capstones

An ecological study was conducted from 19 March 2001 to 2 April 2003 on a population of Spotted Turtles (Clemmys guttata) and Wood Turtles (Glyptemys insculpta) in West Virginia. Live-trapping, mark-recapture, radio telemetry and temperature data logging techniques were used to gather information on morphometrics, capture success, movements, home range, behavior, and thermal regime during activity and over-wintering seasons. Twenty-one Spotted Turtles were captured 260 times. Population structure was 42.9% juvenile, 38.1% male, and 19.0% female. Mean home range was 0.52 ha. Fifty Wood Turtles were captured 230 times. Juveniles were 36%, and males and females were 32% each. Mean …