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El Perro De Monte De Sechura: Su Relación Con El Bosque Seco Tropical Y La Gente De La Región Central De Manabí, Julian O. Buffam

Independent Study Project (ISP) Collection

The Cerro Hojas-Jaboncillo, located in Central Manabí, Ecuador, is a Patrimonial site that, in addition to containing the ruins of an ancient culture, is home to a species of mammal endemic to the tumbesian eco-region. Currently listed by the ‘LibroRojo de los mamíferos del Ecuador’ as vulnerable, the Sechuran Fox (Lycalopexsechurae) is a nocturnal and solitary animal, of a medium size, that is rarely seen due to its elusive behavior. This species is the focus of this investigation, which seeks to gain an understanding of the plants and animals that the Sechuran Fox requires for food, the home …

Mojave Applied Ecology Notes Fall 2011, E. Cayenne Engel, Scott R. Abella, Kathryn A. Prengaman, Jason Whited, Peter Michel

Mojave Applied Ecology Notes

Paper on impacts of Mojave wildfires through time published, possibilities of catastrophic Mt. Charleston forest fires, vegetation mapping at three national parks, UNLV library’s special collections, and the benefits of scientific publications to managers and stakeholders

Rumbling In The Benthos: Acoustic Ecology Of The California Mantis Shrimp Hemisquilla Californiensis, E. Staaterman, C. Clark, A. Gallagher, M. Devries, T. Claverie, S. Patek

Faculty Publications, Biological Sciences

Although much research has focused on acoustic mapping and exploration of the benthic environment, little is known about the acoustic ecology of benthic organisms, particularly benthic crustaceans. Through the use of a coupled audio–video system, a hydrophone array, and an autonomous recording unit, we tested several hypotheses about the field acoustics of a benthic marine crustacean, Hemisquilla califor­niensis. Living in muddy burrows in southern California, these large mantis shrimp produce low frequency ‘rumbles’ through muscle vibrations. First, we tested whether acoustic signals are similar in the field and in the laboratory, and discovered that field-produced rumbles are more acoustically and …

Relationship Of Maternal Flow Environment To Offspring Size In Botrylloides Violaceus, Damion J. Delton, Sarah Cohen

STAR Program Research Presentations

Colonial botryllid tunicates, such as Botrylloides violaceus, brood large, non-feeding offspring with extremely limited larval life spans of minutes to perhaps one day. Despite the importance of this transitory life history stage, there is little information on how environmental factors such as ambient water flow affect larval size among invertebrates. Since adult tunicates feed by filtering particles from the water flowing around the siphons, we reasoned that colonies of B. violaceus in high water flow may produce larger offspring due to greater food availability. We tested to see whether there was a relationship between larval size and water motion in …

Climate And Vegetation Change In The Newberry Mountains, Southern Clark County, Nevada, Ross Joseph Guida

UNLV Theses, Dissertations, Professional Papers, and Capstones

Ecological studies have shown worldwide that vegetation is being affected by climate change. Species are shifting to new elevations and physiographic positions to adapt to changes in their environment. More specifically, paleoecology studies in the Mojave Desert have shown shifting vegetation patterns in response to past warming and precipitation changes. Recent studies have shown mortality among desert plants related to extended drought and warming. However, few studies have shown how the geographic distribution of Mojave Desert species has changed during this most recent period of warming. This study addresses this gap in the literature by focusing on several plant species …

Survival, Breeding Frequency, And Migratory Orientation In The Jefferson Salamander, Ambystoma Jeffersonianum, Stephen P. De Lisle, Kristine L. Grayson

Biology Faculty Publications

Accurate estimates of demographic parameters, such as survival and breeding frequency, are necessary for the conservation and management of animal populations. Additionally, life-history data are required for gaining an empirical understanding of the ecology of natural populations. We monitored a population of Jefferson Salamanders (Ambystoma jeffersonianum) breeding in a permanent mountain-top pond at the southern limit of this species’ geographic range in Virginia over four years. We used closed multistate mark-recapture models with Pollock's robust design to estimate the demographic parameters of this population. Additionally, we used point-of-capture data to compare the orientation of migrations into and out …

Techniques To Promote Garry Oak Seedling Growth And Survival In Areas With High Levels Of Herbivory And Competition, David R. Clements, Seth Luginbill, David A. Jordan, Randall Dragt

University Faculty Publications and Creative Works

Though regeneration of Garry oak (Quercus garryana) seedlings within Garry oak ecosystems is important to maintain this threatened habitat, seedling regeneration is often poor. Two independent studies were initiated in the early 2000s to examine questions surrounding Garry oak recruitment: one at the Crow's Nest Ecological Research Area (CNERA) on Salt Spring Island, BC, and another at the Pacific Rim Institute for Environmental Stewardship (PRI) on Whidbey Island, WA. In both areas, Garry oak seedlings were caged and monitored for growth and relative health. Over 8 years at CNERA, growth of caged plants outpaced growth of controls, which was indicative …

The Distribution And Life Cycle Of Alliaria Petiolate In Lincoln, Nebraska, Caleb Pharris

Department of Environmental Studies: Undergraduate Student Theses

Alliaria petiolata (Garlic Mustard) is a biennial alien invasive plant species of the Brassicacea family. It is responsible for displacing native plant species throughout North America and its management has proven to be extremely difficult. Recently several populations of Alliaria petiolata have been discovered in southwestern Lincoln, Nebraska. The spread of Alliaria petiolata is a concern for natural resource managers and the general public. Due to the difficulty of its control, Alliaria petiolata is capable of creating monocultures which diminish the aesthetic value of an ecosystem. While most commonly found in the understory of hardwood forests, it is capable of …

Life History Benefits Of Residency In A Partially Migrating Pond-Breeding Amphibian, Kristine L. Grayson, Larissa L. Bailey, Henry M. Wilbur

Biology Faculty Publications

Species with partial migration, where a portion of a population migrates and the other remains residential, provide the opportunity to evaluate conditions for migration and test mechanisms influencing migratory decisions. We conducted a five-year study of two populations of red-spotted newts (Notophthalmus viridescens), composed of individuals that either remain as residents in the breeding pond over the winter or migrate to the terrestrial habitat. We used multistate mark-recapture methods to (1) test for differences in survival probability between migrants and residents, (2) determine if migrants breed every year or skip opportunities for reproduction, and (3) estimate the frequency …

Ecotourism In Costa Rica: Environmental Impacts And Management, Emily Mckeone

Department of Environmental Studies: Undergraduate Student Theses

Globally we are witnessing growing environmental destruction, particularly to the natural resource bases of underdeveloped countries. If ecotourism can generate profits for local economies, while protecting and conserving the natural resource base of that community, it could be a strong alternative for numerous countries. Evidence suggests that the ecotourism industry has been expanding at a rapid rate in recent decades (Dasenbrock 2002). It is important to understand the positive and negative ecological impacts of the industry as this rapid growth rate continues.

The main objective of this study is to highlight the strengths and weaknesses of the ecotourism industry in …

An Assessment Of Stable Hydrogen-Isotope Analysis Methods To Assign Geographic Origin To Migratory Red-Tailed Hawks (Buteo Jamaicensis), Carla Marie Ahlschwede

Department of Environmental Studies: Undergraduate Student Theses

Stable-hydrogen isotopes are becoming an increasingly popular method of studying migratory birds, though sample preparation methods may affect results.  In this study I examined feathers from red-tailed hawks (Buteo jamaicensis) to determine the relationship between measure of δD due to inter-feather variation or drying methods, assessed the accuracy of results by using two birds of known-origin and estimated possible natal origins of migratory red-tailed hawks.  Two feathers per individual were taken from 81 wild hawks caught at Hitchcock Nature Center near Crescent IA and from 2 rescued red-tailed hawks, Raptor Recovery Nebraska near Eagle, NE. 119 of the …

Relationships Of Exotic Plant Invasions With Biological Soil Crust, Desert Pavement, And Soil Carbon In The Eastern Mojave Desert, Adria Decorte

UNLV Theses, Dissertations, Professional Papers, and Capstones

In a matter of 50 years, exotic annual plants have become widespread in the Mojave Desert, contributing to drastic landscape changes such as those caused by recent fires. Invasions by exotics threaten native Mojave Desert plant communities by altering community functions (e.g. fire regimes) and by reducing plant diversity. Because it is not practical, or even possible, to eradicate these exotics, developing effective prevention techniques is the key to controlling these invasions.

This thesis used a greenhouse experiment, a field experiment, and a correlational field study to examine the affect soil surface types have on the establishment of three exotic …

Mojave Applied Ecology Notes Spring 2011, Scott R. Abella, Ross Guida, S. D. Smith, Christopher L. Roberts, Haroon Stephen, William J. Smith, Zhongwei Liu, James S. Holland, Aurore Giguet

Mojave Applied Ecology Notes

Red brome distribution in the eastern Mojave Desert, A look at the UNLV xeric gardens and Marjorie Barrick museum, Summary of recent science synthesis efforts

Historic And Contemporary Trends Of The Conservation Reserve Program And Ring-Necked Pheasants In South Dakota, Christopher R. Laingen

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

Over the past century, the interactions between agricultural land use and government cropland retirement programs have affected pheasant population change. Two government land retirement programs that returned croplands to grasslands, Soil Bank in the 1960s and the current Conservation Reserve Program (CRP), help to illustrate these connections. From 2007 to 2010, South Dakota lost 41% of its CRP lands and experienced an 18% decline in pheasants per mile. However, because of where CRP expirations have occurred and where pheasant populations are found, some regional variability is seen. Western South Dakota (Region 1) had an 80% increase in pheasants per mile …

Performance And Reproduction Of An Exotic Invader Across Temperate Forest Gradients, Robert J. Warren Ii, Volker Bahn, Timothy D. Kramer, Yaya Tang, Mark A. Bradford

Biological Sciences Faculty Publications

Widespread colonization by invasive species often obscures their underlying niche requirements. A robust inference into habitat requirements demands direct measures of invasive species performance linked with associated environmental conditions. In the context of general ecological theory, we investigated the niche requirements of Microstegium vimineum, an invasive grass in the U.S. that overruns native vegetation in forest understories. We examined M. vimineum’s performance and reproduction as a function of environmental drivers across forested and unforested habitats along a 100-km regional and climatic gradient in the southeastern U.S. from the southern Appalachian Mountains to the Georgia piedmont. We then measured M. vimineum …

Contrasting Effects Of Flow On Adult And Juvenile Ascidian Life History Stages, Including The Global Invasive Didemnum Vexillum, Tren C. Kauzer, C Sarah Cohen

STAR Program Research Presentations

Few studies have quantified a relationship between recruitment, growth, survival and flow with colonial filter feeders. In this study, the growth of D. vex and larval recruitment were evaluated under different local flow conditions in Half Moon Bay, California, USA. Tunicates were subjected to four different flow conditions, three of which included objects to differentially obstruct flow, and growth and recruitment were measured. A direct relationship was seen between increases in flow and adult growth, and an inverse relationship was seen between increases in flow and recruitment. These trends suggest that optimal flow conditions differ for juveniles and adults. The …

The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds [Presentation], Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)

No abstract provided.

The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)

During the fall of 2011, the Colby Environmental Assessment Team (CEAT) studied the Serpentine connecting East Pond and North Pond. East and North Ponds are members of the larger seven-lake system known as the Belgrade Lakes, located in central Maine. There are over 5,500 lakes in Maine that contribute $6.7 billion to the economy annually through activities including boating, fishing, swimming etc. Additionally, Maine’s lakes are sources of municipal and agricultural water, act as flood buffers, and host a wide range of plant, animal, and fish life. Lakes in Maine are a crucial part society and should be studied and …

Microclimate Preferences Of The Grey-Headed Flying Fox (Pteropus Poliocephalus) In The Sydney Region, Stephanie T. Snoyman, Culum Brown

Sentience Collection

The population size of the grey-headed flying fox (Pteropus poliocephalus) has decreased dramatically as a result of a variety of threatening processes. This species spends a great proportion of time in roosting large social aggregations in urban areas, causing conflict between wildlife and humans. Little is known about why these bats choose to roost in some locations in preference to others. Roost selection by cave-dwelling bats can be greatly influenced by microclimatic variables; however, far less is known about microclimate selection in tree-roosting species despite the direct management implications. This study aimed to determine the microclimate characteristics of P. poliocephalus …

Mojave Applied Ecology Notes Winter 2011, Scott R. Abella, Alice C. Newton, Kenneth Chittick, Pam Sinanian

Mojave Applied Ecology Notes

Lake Mead’s collaborative applied science research program; “annoying the elephant” - ruminations on active management by Alice Newton, Lake Mead NRA vegetation manager; 2012 NWRA Lake Mead symposium sneak peak; assessing forest change using dendrochronology in the Spring Mountains.

Gordon Natural Area Tour - Guide, Kendra Mcmillin, Gerard Hertel

Gordon Natural Area-related Curricula Documents

No abstract provided.

Buffernomics: Assessing Willingness To Pay For Lake Conservation On North Pond And East Pond, Sophie D. Sarkar

Honors Theses

Hedonic property valuations in Maine have estimated that a one-meter decrease in water clarity can reduce shoreline property values by 4 to 16%. To avoid a loss on their lakefront investment, shoreline property owners have a particularly large incentive to conserve lake water quality. Nevertheless, while some shoreline residents voluntarily install vegetated buffers and actively participate in lake stewardship, others continue to ignore shoreline zoning laws at the expense of lake health. In this thesis, I examine the dichotomy of active and indifferent shoreline residents by analyzing the motivations that distinguish residents who are willing to pay (WTP) for and …

Zooplankton Of The Belgrade Lakes: The Influence Of Top-Down And Bottom-Up Forces In Family Abundance, Kimberly M. Bittler

Honors Theses

The purpose of this study was to assess the abundance and family diversity of zooplankton communities in the Belgrade Lakes, and to identify the broad scale and local variables that structure zooplankton communities in this region. The local effects of shoreline development and the presence of macrophyte patches were compared to larger scale variables, such as watershed wide residential development. Zooplankton are an intermediate link in the freshwater food web, and communities respond both to predation pressures as well as nutrient inputs. Shoreline development was expected to influence zooplankton densities by the increased nutrient inputs via erosion off developed sites …

Biomass Energy At Colby College, Rachel E. Baron

Honors Theses

In light of growing concern regarding the effects of global climate change, Colby College signed the American College and University Presidents’ Climate Commitment (ACUPCC) in 2008. Through this pledge, Colby has committed to reducing carbon emissions in its Climate Action Plan (IPCC 2007; CCAP 2010). The College seeks to be carbon neutral by 2015 (CCAP 2010). This will be accomplished through a variety of mechanisms, one of which includes the construction of a biomass facility to replace most of the oil currently used for heating (CCAP 2010).

Anthropogenic global climate change has been documented by many scientists, but was widely …

The One That Carries You Away: Essays, Blair S. Braverman

Honors Theses

What is environmental writing? Phil Condon, author and professor at the University of Montana's Environmental Writing Institute, defines it as any piece of writing in which an important factor is nonhuman—be it animal, place, weather, et cetera. At the same time, he acknowledges that the primary limitation of this definition is its lack of limitations; because humans are constantly interacting with—and affected by—the nonhuman, virtually any piece of writing could be considered environmental. The Association for the Study of Literature and the Environment (ASLE), the nation's predominant organization for the academic study of environmental writing, defines itself through its focus …

Cultural Botany: Toward A Model Of Transdisciplinary, Embodied, And Poetic Research Into Plants, John C. Ryan

Research outputs 2011

Since the eighteenth century, the study of plants has reflected an increasingly mechanized and technological view of the natural world that divides the humanities and the natual sciences. In broad terms, this article proposes a context for research into flora through an interrogation of existing literature addressing a rapprochement between ways to knowledge. The natureculture dichotomy, and more specifically the plant-to-human sensory disjunction, follows a parallel course of resolution to the schism between objective (technical, scientific, reductionistic, visual) and subjective (emotive, artistic, relational, multi-sensory) forms of knowledge. The foundations of taxonomic botany, as well as the allied fields of environmental …

A Standardized Design For Quagga Mussel Monitoring In Lake Mead, Nevada-Arizona, Wai Hing Wong, Shawn Gerstenberger, Jennell M. Miller, Craig Palmer, Bryan Moore

Environmental & Global Health Faculty Research

The discovery of quagga mussels (Dreissena rostriformis bugensis) in Lake Mead, Nevada-Arizona, on January 6, 2007 is the first known occurrence of dreissenid species in the western United States. This study developed elements of a cost-effective and standardized quagga mussel-monitoring program for Lake Mead using preliminary data to arrive at statistically based numbers of sampling sites. To represent the abundance of adult/juvenile quagga mussels in Lake Mead’s heterogeneous floor with 95% confidence, a stratified simple random sampling design revealed a requirement of 41 samples from hard substrates (i.e., rocky areas) and 97 samples from soft substrates (i.e., sandy and muddy …

The Role Of Nature In John Muir's Conception Of The Good Life, Randy R. Larsen

Antioch University Dissertations & Theses

Aristotle says our best moral guidance comes from considering the lives of exemplary individuals. I explore John Muir, as an exemplar of environmental virtue, and consider the role of Nature in his conception of the good life. I argue his conception consists of a web of virtue including various goods, values, and virtues. I suggest three virtues are cardinal: attentiveness, gratitude and reverence. I explore how Muir cultivated these virtues in Nature.

I argue Muir sought freedom from a popular conception of the good life, grounded in the gilded age values of money and materialism, and was sensitive to the …

Range Extension For The Dismal Swamp Southern Bog Lemming, Synaptomys Cooperi Helaletes, In Eastern Virginia, Robert K. Rose

Biological Sciences Faculty Publications

The distribution of the Dismal Swamp Southern Bog Lemming is extended to include three counties west of the Dismal Swamp in southeastern Virginia, long considered its only location in the state. Evidence of lemmings was detected at 10 of 27 survey sites, and confirmed by trapping at three of five sites, all dominated by herbaceous vegetation.

Salmon For Terrestrial Protected Areas, Chris T. Darimont, Heather M. Bryan, Stephanie M. Carlson, Morgan D. Hocking, Misty Macduffee, Paul C. Paquet, Michael H. H. Price, Thomas E. Reimchen, John D. Reynolds, Christopher C. Wilmers

Environment and Nature Conservation Collection

Although managers safeguard protected areas for migratory species, little consideration has been given to how migratory species might benefit parks. Additionally, whereas land‐sea connections are considered in management of protected areas, most effort has focused on reducing negative “downstream” processes. Here, we offer a proposal to promote positive “upstream” processes by safeguarding the seasonal pulse of marine nutrients imported into freshwater and riparian ecosystems by spawning migrations of Pacific salmon. Currently, high rates of fishing limit this important contribution to species and processes that terrestrial parks were designed to protect. Accordingly, we propose limiting exploitation in areas and periods through …