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Life History Benefits Of Residency In A Partially Migrating Pond-Breeding Amphibian, Kristine L. Grayson, Larissa L. Bailey, Henry M. Wilbur 2011 University of Richmond

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 …


Population Dynamics Of The Western Prickly Pear, Opuntia Macrorhiza (Cactaceae), Kathleen H. Keeler, Brigitte Tenhumberg 2011 University of Nebraska - Lincoln

Population Dynamics Of The Western Prickly Pear, Opuntia Macrorhiza (Cactaceae), Kathleen H. Keeler, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Although most cacti that have been studied are long lived, following individually marked plants in Boulder County, Colorado, for >7 years, we determined that average life span of Opuntia macrorhiza, the western prickly pear, is 3 years. A few individuals probably live >10 years. Vegetative reproduction, produced by rooting of cladodes, exceeded reproduction by germination and establishment from seeds. Both types of new recruits, from vegetative reproduction and seeds, had higher death rates than established plants. Size and frequency of flowering increased with age, although size both increased and decreased, sometimes dramatically, between years. Flowering correlated more strongly with …


Botteri's Sparrow (Peucaea Botterii) Occurs In Northern Coahuila, Mexico, Paul van Els, Ricardo Canales-del-Castillo, John Klicka 2011 University of Nevada, Las Vegas

Botteri's Sparrow (Peucaea Botterii) Occurs In Northern Coahuila, Mexico, Paul Van Els, Ricardo Canales-Del-Castillo, John Klicka

Ornithology Program (HRC)

Botteri’s Sparrow (Peucaea botterii) occurs widely in the shrub-grasslands of southern North America. We report a breeding population of the species in the Sierra de la Encantada of northern Coahuila, Mexico, ~80 km from the Big Bend area of Texas and >300 km from the nearest previously known breeding range in southern Coahuila and central Chihuahua. We captured three individuals, which show a mostly gray dorsal coloration, suggestive of the texana subspecies, occurring from southern Texas to northern Veracruz. The exact affinity of the northern Coahuila population still needs to be ascertained. The presence of Botteri’s Sparrow in northern Coahuila …


A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt 2011 Texas Parks and Wildlife Department

A Mark–Recapture Technique For Monitoring Feral Swine Populations, Matthew M. Reidy, Tyler A. Campbell, David G. Hewitt

United States Department of Agriculture Wildlife Services: Staff Publications

Techniques to monitor populations of feral swine (Sus scrofa) relative to damage control activities are needed on rangelands. Our objectives were to describe and assess a mark–recapture technique using tetracycline hydrochloride (TH) for monitoring feral swine populations. We established bait stations at study sites in southern and central Texas. During 1 d, we replaced normal soured corn bait with bait containing TH and counted the number of feral swine that consumed bait with observers. We conducted feral swine removal using box-style traps and helicopters, at which time we collected teeth for TH analysis. In southern Texas, we estimated …


The Role Of Historical And Contemporary Processes On Phylogeographic Structure And Genetic Diversity In The Northern Cardinal, Cardinalis Cardinalis, Brian T. Smith, Patricia Escalante, Blanca E. Hernandez-Banos, Adolfo G. Navarro-Siguenza, Sievert Rohwer, John Klicka 2011 University of Nevada, Las Vegas

The Role Of Historical And Contemporary Processes On Phylogeographic Structure And Genetic Diversity In The Northern Cardinal, Cardinalis Cardinalis, Brian T. Smith, Patricia Escalante, Blanca E. Hernandez-Banos, Adolfo G. Navarro-Siguenza, Sievert Rohwer, John Klicka

Ornithology Program (HRC)

Background

Earth history events such as climate change are believed to have played a major role in shaping patterns of genetic structure and diversity in species. However, there is a lag between the time of historical events and the collection of present-day samples that are used to infer contemporary population structure. During this lag phase contemporary processes such as dispersal or non-random mating can erase or reinforce population differences generated by historical events. In this study we evaluate the role of both historical and contemporary processes on the phylogeography of a widespread North American songbird, the Northern Cardinal, Cardinalis cardinalis …


The Decline And Conservation Status Of North American Bumble Bees, Jonathan Berenguer Koch 2011 Utah State University

The Decline And Conservation Status Of North American Bumble Bees, Jonathan Berenguer Koch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several reports of North American bumble bee (Bombus Latreille) decline have been documented across the continent, but no study has fully assessed the geographic scope of decline. In this study I discuss the importance of Natural History Collections (NHC) in estimating historic bumble bee distributions and abundances, as well as in informing current surveys. To estimate changes in distribution and relative abundance I compare historic data assembled from a >73,000 specimen database with a contemporary 3-year survey of North American bumble bees across 382 locations in the contiguous U.S.A. Based on my results, four historically abundant bumble bees, B. …


Does Thermal Stress Cause Females Of The Plant Bryum Argenteum To Manipulate The Sex Ratios Of Their Offspring?, Elisha Rhodes, Lloyd Stark 2011 University of Nevada, Las Vegas

Does Thermal Stress Cause Females Of The Plant Bryum Argenteum To Manipulate The Sex Ratios Of Their Offspring?, Elisha Rhodes, Lloyd Stark

Festival of Communities: UG Symposium (Posters)

About half of all moss taxa exhibit female-biased sex ratios, and bryophyte male rarity remains largely unexplained. One possible explanation is differential stress tolerance of spores due to maternal sporophyte manipulation during stress. To test this hypothesis, sporophytes of the species Bryum argenteum were subjected to thermal stress and observed for growth abnormalities and sporophyte abortions. Data display a correlation between increased temperature and increased sporophyte abortions as well as increased time to complete meiosis, possibly indicating decreased fitness. Continued global warming may create more stressful environments for sporophytes resulting in the elimination of males from local populations.


Review Of Nature's Ghosts: Confronting Extinction From The Age Of Jefferson To The Age Of Ecology. By Mark V. Barrow, Jr., Peter A. Bednekoff 2011 Eastern Michigan University

Review Of Nature's Ghosts: Confronting Extinction From The Age Of Jefferson To The Age Of Ecology. By Mark V. Barrow, Jr., Peter A. Bednekoff

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

The saving of bison occupies a central place in Nature's Ghosts, but Mark Barrow's chronicle extends over a century both before and after. The story starts with Thomas Jefferson and fossils that came to be recognized as mastodons, mammoths, and giant ground sloths. "Jefferson and most of his contemporaries were certain that the natural world was orderly, static, and new." In such a worldview, extinction was unthinkable. Fossil evidence plus the historical extinctions of dodos, moas, and great auks forced reconsideration.

This book ranges across centuries and continents, and only a few parts of it are explicitly about the Great …


Health And Fertility Implications Related To Seasonal Changes In Kidney Fat Index Of White-Tailed Jackrabbits In South Dakota, Dustin Schaible, Charles D. Dieter 2011 Utah Division of Wildlife Resources

Health And Fertility Implications Related To Seasonal Changes In Kidney Fat Index Of White-Tailed Jackrabbits In South Dakota, Dustin Schaible, Charles D. Dieter

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

White-tailed jackrabbit (Lepus townsendii) populations in the Northern Plains have been in a general decline for the past decade or longer. A suggested reason for this population decline was reduced body condition of individual jackrabbits due to habitat changes. In order to evaluate body condition, we determined the kidney fat index of 314 white-tailed jackrabbits harvested in 44 counties throughout South Dakota. We removed and weighed kidneys and all perirenal fat associated with the kidneys from collected jackrabbits. We measured kidney weight to determine times of high metabolic activity as indicated by an increase in mass. Body condition was …


Governance Of The Western Rock Lobster Fishery And Marine Stewardship Council Principle 3 Effective Management, Department of Fisheries 2011 Department of Primary Industries and Regional Development, Western Australia

Governance Of The Western Rock Lobster Fishery And Marine Stewardship Council Principle 3 Effective Management, Department Of Fisheries

Fisheries Occasional Publications

No abstract provided.


Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis 2011 University of Nebraska-Lincoln

Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis

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

Accurate knowledge of species boundaries and species phylogeny are fundamental to testing hypotheses of recent evolutionary processes, but the estimation of these partitions is challenging due both to inherent confusion about what is being estimated as well as the data available to estimate them. Using multilocus data from mtDNA, microsatellites, and nuclear locus sequences of over 1100 individuals, we delimited eight separately evolving species of Cichla rather than the 15 described. Among species we found evidence of rare but widespread introgressive hybridization, while within these species we observed evidence of long-term gene exchange and constrained evolutionary trajectories. In most cases …


Effects Of Water Quality On Genetic Variation On The Brackish-Water Rotifer Brachionus Plicatilis, Kayla I. Hinson^, Elizabeth J. Walsh* 2011 Department of Biological Sciences, University of Texas at El Paso

Effects Of Water Quality On Genetic Variation On The Brackish-Water Rotifer Brachionus Plicatilis, Kayla I. Hinson^, Elizabeth J. Walsh*

COURI Symposium Abstracts, Spring 2011

Impacts of water quality on the genetic structure of aquatic organisms have not been well characterized. Unfavorable conditions may result in loss of species diversity and/ or select for tolerant genotypes. We investigated whether aquatic pollutants affect the genetic diversity of the rotifer Brachionus plicatilis, common in saline systems. We predict that the genetic diversity of B. plicatilis will decrease with lower water quality. An urban population (Ascarate Lake, El Paso Co., TX) was compared with a non-impacted population (Figure 8 Lake, Bottomless Lakes, NM). Basic water chemistry parameters were measured along with heavy metals concentrations. Genetic variation is …


Integrating Values And Ethics Into Wildlife Policy And Management—Lessons From North America, Camilla H. Fox, Marc Bekoff 2011 Animal Welfare Institute

Integrating Values And Ethics Into Wildlife Policy And Management—Lessons From North America, Camilla H. Fox, Marc Bekoff

Conservation Collection

Few animals provoke as wide a range of emotions as wolves. Some see wolves as icons of a lost wilderness; others see them as intruders. As the battle continues between wolf proponents and opponents, finding solutions that resolve conflicts while supporting the integrity of nature is challenging. In this essay we argue that we need to make room for wolves and other native carnivores who are re-colonizing areas from which they were extirpated. Strategies that foster coexistence are necessary and wildlife agencies must consider all stakeholders and invest adequate resources to inform the public about how to mitigate conflicts between …


Trap Shyness And Avoidance Affects On Capture Proportions Of Dipodomys Heermanni Arenae, Natalie E. Folsom, Andrew R. Ruddock 2011 California Polytechnic State University, San Luis Obispo

Trap Shyness And Avoidance Affects On Capture Proportions Of Dipodomys Heermanni Arenae, Natalie E. Folsom, Andrew R. Ruddock

Biological Sciences

This is a study on trap shyness and trap avoidance in the kangaroo rat species Dipodomys heermanni arenae. This species is being studied as a surrogate for the critically endangered Dipodomys heermanni morroensis. This is an ongoing study that has been continuing for the past three years, with four three-day sessions per year. The study is a specific look at the effects of the use of Sherman traps on kangaroo rat behavior between individual session days. Capture proportions for each of the three days of each session were calculated and compared through a t-test. The current results of …


Factors Affecting Space Use Overlap By White-Tailed Deer In An Urban Landscape, W. David Walter, Jeff Beringer, Lonnie P. Hansen, Justin W. Fischer, Joshua J. Millspaugh, Kurt C. Vercauteren 2011 National Wildlife Research Center

Factors Affecting Space Use Overlap By White-Tailed Deer In An Urban Landscape, W. David Walter, Jeff Beringer, Lonnie P. Hansen, Justin W. Fischer, Joshua J. Millspaugh, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Variation in the size and overlap of space use by white-tailed deer (Odocoileus virginianus) has broad implications for managing deer–human conflicts and disease spread and transmission in urban landscapes. Understanding which factors affect overlap of home range by various segments (i.e., age, sex) of an urban deer population has implications to direct contact between deer on disease epidemiology. We assessed size of home range and overlap of space use using the volume of intersection index (VI) for deer in an urban landscape by sex, age, season, and time of day. We found mean space use was larger for …


Songbird Diversity In Oak Woodland And Riparian Habitats In The Los Padres National Forest, San Luis Obispo County, California, Trevor Pell 2011 California Polytechnic State University, San Luis Obispo

Songbird Diversity In Oak Woodland And Riparian Habitats In The Los Padres National Forest, San Luis Obispo County, California, Trevor Pell

Biological Sciences

Diversity in songbirds (Passeriformes) between riparian and oak woodland habitats has not been studied before in the Los Padres National Forest around the Hi Mountain Lookout in San Luis Obispo County. Surveys of avian populations were conducted by point counts on fifty variable circular plots; surveys were performed between July and August of 2010. Diversity was calculated using the Shannon-Weiner method, and then squared for normality. No significant results were found when comparing the diversity values between riparian and oak woodland habitat (F = 0.52, p = 0.472). Although the results showed no significance, the data are still important, as …


Contrasting Effects Of Flow On Adult And Juvenile Ascidian Life History Stages, Including The Global Invasive Didemnum Vexillum, Tren C. Kauzer, C Sarah Cohen 2011 California Polytechnic State University - San Luis Obispo

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 …


Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post van der Burg, Andrew J. Tyre 2011 University of Nebraska-Lincoln

Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post Van Der Burg, Andrew J. Tyre

School of Natural Resources: Faculty Publications

Wildlife managers often make decisions under considerable uncertainty. In the most extreme case, a complete lack of data leads to uncertainty that is unquantifiable.Information-gap decision theory deals with assessing management decisions under extreme uncertainty, but it is not widely used in wildlife management. So too, robust population management methods were developed to deal with uncertainties in multiple-model parameters.However, the two methods have not, as yet, been used in tandem to assess population management decisions. We provide a novel combination of the robust population management approach for matrix models with the information-gap decision theory framework for making conservation decisions under extreme …


Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels 2011 University of Nebraska at Lincoln

Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels

School of Natural Resources: Faculty Publications

As more and more organizations with responsibility for natural resource management adopt adaptive management as the rubric in which they wish to operate, it becomes increasingly important to consider the sources of uncertainty inherent in their endeavors. Without recognizing that uncertainty originates both in the natural world and in human undertakings, efforts to manage adaptively at the least will prove frustrating and at the worst will prove damaging to the very natural resources that are the management targets. There will be more surprises and those surprises potentially may prove at the very least unwanted and at the worst devastating. We …


Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. McFadden, Tim L. Hiller, Andrew J. Tyre 2011 University of Nebraska-Lincoln

Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. Mcfadden, Tim L. Hiller, Andrew J. Tyre

School of Natural Resources: Faculty Publications

Within the field of natural-resources management, the application of adaptive management is appropriate for complex problems high in uncertainty. Adaptive management is becoming an increasingly popular management-decision tool within the scientific community and has developed into two primary schools of thought: the Resilience-Experimentalist School (with high emphasis on stakeholder involvement, resilience, and highly complex models) and the Decision-Theoretic School (which results in relatively simple models through emphasizing stakeholder involvement for identifying management objectives). Because of these differences, adaptive management plans implemented under each of these schools may yield varying levels of success. We evaluated peer-reviewed literature focused on incorporation of …


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