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A Tragedy Exposed? Clear Growth Medium Reveals Competing Roots, Christopher H. Karounos, Deric Miller, Philip Crowley, Nicholas McLetchie 2014 University of Kentucky

A Tragedy Exposed? Clear Growth Medium Reveals Competing Roots, Christopher H. Karounos, Deric Miller, Philip Crowley, Nicholas Mcletchie

Kaleidoscope

Abstract

Tragedy of the Commons (ToC) is the exploitation of an open-access resource that is exploited by selfish individuals to the detriment of all. Examples include open sea fisheries, cattle grazing, pollution, deforestation and plants competing over shared soil nutrients and space. Tragically, these resources become depleted and plants become severely resource limited. Our study seeks to determine if a ToC causes two plants sharing resources to reproduce less successfully than two plants owning the equivalent amount of personal resources. We predict that plant root competition creates a ToC by increasing root mass while reducing reproductive mass. Our study uses ...


Getting In Deep, Earl Smith 2014 Colby College

Getting In Deep, Earl Smith

Colby Magazine

Cleaning up Johnson Pond required wading through a quagmire of regulations- and produced some surprising revelations.


Report On The Workshop For Life Detection In Samples From Mars, Gerhard Kminek, Catherine Conley, Carlton C. Allen, Douglas H. Bartlett, David W. Beaty, Liane G. Benning, Rohit Bhartia, Penelope J. Boston, Caroline Duchaine, Jack D. Farmer, George J. Flynn, Daniel P. Glavin, Yuri Gorby, John E. Hallsworth, Rakesh Mogul, Duane Moser, P. Buford Price, Ruediger Pukall, David Fernandez-Remolar, Caroline L. Smith, Kenneth M. Stedman, Andrew Steele, Ramunas Stepanauskas, Henry Sun, Jorge L. Vago, Mary A. Voytek, Paul S. Weiss, Frances Westfall 2014 Portland State University

Report On The Workshop For Life Detection In Samples From Mars, Gerhard Kminek, Catherine Conley, Carlton C. Allen, Douglas H. Bartlett, David W. Beaty, Liane G. Benning, Rohit Bhartia, Penelope J. Boston, Caroline Duchaine, Jack D. Farmer, George J. Flynn, Daniel P. Glavin, Yuri Gorby, John E. Hallsworth, Rakesh Mogul, Duane Moser, P. Buford Price, Ruediger Pukall, David Fernandez-Remolar, Caroline L. Smith, Kenneth M. Stedman, Andrew Steele, Ramunas Stepanauskas, Henry Sun, Jorge L. Vago, Mary A. Voytek, Paul S. Weiss, Frances Westfall

Biology Faculty Publications and Presentations

The question of whether there is or was life on Mars has been one of the most pivotal since Schiaparellis’ telescopic observations of the red planet. With the advent of the space age, this question can be addressed directly by exploring the surface of Mars and by bringing samples to Earth for analysis. The latter, however, is not free of problems. Life can be found virtually everywhere on Earth. Hence the potential for contaminating the Mars samples and compromising their scientific integrity is not negligible. Conversely, if life is present in samples from Mars, this may represent a potential source ...


Across-Year Social Stability Shapes Network Structure In Wintering Migrant Sparrows, Daizaburo Shizuka, Alexis S. Chaine, Jennifer Anderson, Oscar Johnson, Inger Marie Laursen, Bruce E. Lyon 2014 University of Nebraska - Lincoln

Across-Year Social Stability Shapes Network Structure In Wintering Migrant Sparrows, Daizaburo Shizuka, Alexis S. Chaine, Jennifer Anderson, Oscar Johnson, Inger Marie Laursen, Bruce E. Lyon

Faculty Publications in the Biological Sciences

Migratory birds often form flocks on their wintering grounds, but important details of social structure such as the patterns of association between individuals are virtually unknown. We analysed networks of co-membership in short-term flocks for wintering golden-crowned sparrows (Zonotrichia atricapilla) across three years and discovered social complexity unsuspected for migratory songbirds. The population was consistently clustered into distinct social communities within a relatively small area (~ 7 ha). Birds returned to the same community across years, with mortality and recruitment leading to some degree of turnover in membership. These spatiotemporal patterns were explained by the combination of space use and social ...


New Species Of Ctenomys Blainville 1826 (Rodentia: Ctenomyidae) From The Lowlands And Central Valleys Of Bolivia, Scott Lyell Gardner, Jorge Salazar Bravo, Joseph A. Cook 2014 University of Nebraska - Lincoln

New Species Of Ctenomys Blainville 1826 (Rodentia: Ctenomyidae) From The Lowlands And Central Valleys Of Bolivia, Scott Lyell Gardner, Jorge Salazar Bravo, Joseph A. Cook

Faculty Publications from the Harold W. Manter Laboratory of Parasitology

The genus Ctenomys Blainville 1826 is one of the most diverse of South American hystricognath rodents. Currently, nine species of tuco-tucos are reported from Bolivia, four at elevations above 2,000 m and five inhabiting the lowlands (< 1,000 m). In the present paper, morphology, karyology, and phylogenetic analyses of DNA sequences for a mitochondrial locus were used to assess the taxonomic status of specimens of Ctenomys from localities beyond the previously known ranges of these rodents in the departments of Chuquisaca, Cochabamba, Santa Cruz, and Tarija. Based on these analyses, we describe four new species in the genus Ctenomys, all apparently endemic to the country. In addition, we place Ctenomys goodfellowi Thomas 1921 in synonymy under C. boliviensis Waterhouse 1848 and confirm the presence of C. nattereri Wagner ...


Assessing Landscape Constraints On Species Abundance: Does The Neighborhood Limit Species Response To Local Habitat Conservation Programs?, Christopher F. Jorgensen, Larkin A. Powell, Jeffrey J. Lusk, Andrew A. Bishop, Joseph J. Fontaine 2014 University of Nebraska - Lincoln

Assessing Landscape Constraints On Species Abundance: Does The Neighborhood Limit Species Response To Local Habitat Conservation Programs?, Christopher F. Jorgensen, Larkin A. Powell, Jeffrey J. Lusk, Andrew A. Bishop, Joseph J. Fontaine

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Landscapes in agricultural systems continue to undergo significant change, and the loss of biodiversity is an ever-increasing threat. Although habitat restoration is beneficial, management actions do not always result in the desired outcome. Managers must understand why management actions fail; yet, past studies have focused on assessing habitat attributes at a single spatial scale, and often fail to consider the importance of ecological mechanisms that act across spatial scales. We located survey sites across southern Nebraska, USA and conducted point counts to estimate Ring-necked Pheasant abundance, an economically important species to the region, while simultaneously quantifying landscape effects using a ...


Identifying The Role Of Non-Native Species In The Enhanced Trophic Transfer Of Mercury In The Food Web Of Lake Erie, A North American Great Lake, Kaylin M.S. Liznick 2014 Western University

Identifying The Role Of Non-Native Species In The Enhanced Trophic Transfer Of Mercury In The Food Web Of Lake Erie, A North American Great Lake, Kaylin M.S. Liznick

University of Western Ontario - Electronic Thesis and Dissertation Repository

Increasing mercury (Hg) concentrations in top predatory fish is concerning for human and wildlife health. This study examined the amount of Hg available to the food web of Lake Erie, and explored the role that two recently established non-native species, dreissenid mussels and round goby, have played in the trophic transfer of Hg to sport fish. A comprehensive sampling of total Hg (THg) and methylmercury (MeHg) within Lake Erie water, sediment and seston with high temporal and spatial resolution describes environmental concentrations. In addition, biotic THg and MeHg are quantified in benthic invertebrates and three fish species. A steep spatial ...


Early Song Discrimination By Nestling Sparrows In The Wild, Daizaburo Shizuka 2014 University of Nebraska - Lincoln

Early Song Discrimination By Nestling Sparrows In The Wild, Daizaburo Shizuka

Faculty Publications in the Biological Sciences

Songs play an important role in premating isolation in birds. However, when songs are learned, expe- rience with both conspecific and heterospecific songs in early life could lead to the development of both mixed songs and mixed preferences. One way that such learning errors can be prevented is if birds can discriminate between songs of different species prior to learning and preferentially memorize conspe- cific songs. Prior captive studies have shown that white-crowned sparrows, Zonotrichia leucophrys, are able to discriminate songs early in the process of song memorization, after about 10 days since hatching. I studied early song discrimination in ...


Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher 2014 California Polytechnic State University

Photosynthetic Thermal Tolerance And Recovery To Short Duration Temperature Stress In Desert And Montane Plants: A Comparative Study, David William Gallagher

Master's Theses and Project Reports

  • Climate change models predict an increase in frequency and amplitude of extreme weather events, including heat waves. To better predict how the composition and distribution of plant assemblages might respond to these changes in temperature, it is important to understand how species currently respond to these extremes. Photosynthetic thermal tolerance (T25)and photosynthetic recovery (RT25) were quantified in 27 species. We also studied the relationships between T25, RT25 and leaf mass per area (LMA). Leaf temperature was also monitored in the field.
  • Leaves used in this study were collected from two distinct environments representing desert and ...


Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst 2014 California Polytechnic State University

Investigating Meter Scale Topographic Variation As A Factor Of Monterey Pine (Pinus Radiata) Growing Conditions At Kenneth Norris Rancho Marino Reserve, Cambria, Ca, William J. Meyst

Natural Resources Management and Environmental Sciences

Endemic Monterey pine (Pinus radiata) is limited to three locations in California due to its unique ecological requirements. This project was conducted to investigate spatial growth patterns ofMonterey pine over complex ground surfaces. The coastal hills of Rancho Marino Reserve, Cambria, were surveyed using four 150-m transects to quantify and record ground surface features and growing conditions ofMonterey pine. Changes in elevation of each transect were measured using an Abney level. Linear ground surfaces were found at 86% (344 of 400) of survey nodes. Convex ground surfaces were found at 10.5% of survey nodes (42 of 400). Of the ...


Conclusive Evidence Of Replication Of A Plant Virus In Honeybees Is Lacking, W. Allen Miller, Jimena Carrillo-Tripp, Bryony C. Bonning, Adam G. Dolezal, Amy L. Toth 2014 Iowa State University

Conclusive Evidence Of Replication Of A Plant Virus In Honeybees Is Lacking, W. Allen Miller, Jimena Carrillo-Tripp, Bryony C. Bonning, Adam G. Dolezal, Amy L. Toth

Entomology Publications and Papers

The recent article by Li et al. (1) lacks adequate evidence to support the authors’ assertion that a plant virus propagates or replicates in honeybees. Instead, it is possible that tobacco ringspot virus (TRSV) virions associate with the honeybee and parasitic Varroa mites in the absence of TRSV replication.


Use Of Coastal Islands By Seabirds: A Tool To Guide Future Marine Protected Areas In California, Dana A. Page 2014 University of San Francisco

Use Of Coastal Islands By Seabirds: A Tool To Guide Future Marine Protected Areas In California, Dana A. Page

Master's Projects

Seabird breeding colonies on islands off the coast of California offer a unique tool to help guide marine spatial planning. The life histories of seabirds can be used to develop locations of ecological importance along the coast of California. Tracking methodologies and habitat modeling related to seabird habitat utilization can be used to inform management approaches which can aid in the expansion of marine protected areas (MPAs). Protecting ocean habitats will help mitigate impacts of climate change and ensure the ecosystem services provided by marine environments. Areas within the Monterey Bay National Marine Sanctuary were analyzed to locate candidate MPA ...


Environmental Flow Regime Recommendations For The Promotion Of Salicaceae Seedling Recruitment In California’S Central Valley, Nicholas J. Torrez 2014 University of San Francisco

Environmental Flow Regime Recommendations For The Promotion Of Salicaceae Seedling Recruitment In California’S Central Valley, Nicholas J. Torrez

Master's Projects

Rivers around the world are being degraded due to alteration of natural flow regimes caused by the creation of dams and diversions to serve human needs for water. Alteration to natural flow regime affects a river’s flow magnitude, frequency, duration, timing, and rate of change of flow. These changes have major repercussions on the processes that drive riparian ecosystems. Repercussions to river processes are manifested in the degradation of riparian forest health. This is evident in the rivers of California’s Central Valley, where altered flow regimes are present in all of its major rivers. As a result, Salicaceae ...


Status And Trend In The Southern California Spiny Lobster Fishery And Population: 1980-2011., Eric Miller 2014 Occidental College

Status And Trend In The Southern California Spiny Lobster Fishery And Population: 1980-2011., Eric Miller

Bulletin of the Southern California Academy of Sciences

The California spiny lobster (Panulirus interruptus) fishery in southern California ranks amongst the State's most economically important fisheries. An analysis of commercial harvest data confirms that the fishery was landing near-record catches in the late-2000s through early-2010s. Advances in recreational fishing technology likely tempered commercial fishery landings per unit effort. The commercial catch per trap pulled declined 15%, on average, in years after the introduction of a new rigid-style hoop net in the recreational fishery. Fishery-independent data sourced from power plant marine life monitoring recorded increased California spiny lobster abundance after 1989 with evidence of increased larval settlement beginning ...


Black Bears (Ursus Americanus) As A Novel Potential Predator Of Agassiz’S Desert Tortoises (Gopherus Agassizii) At A California Wind Energy Facility, Jeffrey Lovich, David Delaney, Jessica Briggs, Mickey Agha, Meaghan Austin, Jason Reece 2014 Occidental College

Black Bears (Ursus Americanus) As A Novel Potential Predator Of Agassiz’S Desert Tortoises (Gopherus Agassizii) At A California Wind Energy Facility, Jeffrey Lovich, David Delaney, Jessica Briggs, Mickey Agha, Meaghan Austin, Jason Reece

Bulletin of the Southern California Academy of Sciences

Black bears (Ursus americanus) and Agassiz’s desert tortoises (Gopherus agassizii) rarely interact due to substantial differences in their preferred habitats. In this paper we report a mother and cub black bear investigating an occupied tortoise burrow in a wind energy generation facility in the San Bernardino Mountains northwest of Palm Springs, California. While predation was not observed, bears are known to eat various turtle species around the world on an opportunistic basis. Given the proclivity of black bears to adopt specialized dietary opportunities on a learned, individual basis, the potential exists for predation on desert tortoises. Since black bears ...


Flight Initiation Distance Differs Between Populations Of Western Fence Lizards (Sceloporus Occidentalis) At A Rural And An Urban Site, Elizabeth K. Grolle, Michelle C. Lopez, Marina M. Gerson 2014 Occidental College

Flight Initiation Distance Differs Between Populations Of Western Fence Lizards (Sceloporus Occidentalis) At A Rural And An Urban Site, Elizabeth K. Grolle, Michelle C. Lopez, Marina M. Gerson

Bulletin of the Southern California Academy of Sciences

Abstract.—Flight initiation distance (FID) is the distance to which a predator is permitted to approach before the prey initiates flight behavior. This can be influenced by factors including predator density and distance to cover. We measured flight initiation distances in two populations of Western fence lizards (Sceloporus occidentalis), one in a rural and one in an urban environment. Lizards at the rural site initiated flight at significantly longer distances than those at the urban site. These results support the prediction that lizard behavior can be influenced by differences in human exposure and predator recognition in their environments. Lizards develop ...


Coastal Range And Movements Of Common Bottlenose Dolphins (Tursiops Truncatus) Off California And Baja California, Mexico, Alice Hwang, Richard H. Defran, Maddalena Bearzi, Daniela Maldini, Charles A. Saylan, Aimée R. Lang, Kimberly J. Dudzik, Oscar R. Guzòn-Zatarain, Dennis L. Kelly, David W. Weller 2014 Occidental College

Coastal Range And Movements Of Common Bottlenose Dolphins (Tursiops Truncatus) Off California And Baja California, Mexico, Alice Hwang, Richard H. Defran, Maddalena Bearzi, Daniela Maldini, Charles A. Saylan, Aimée R. Lang, Kimberly J. Dudzik, Oscar R. Guzòn-Zatarain, Dennis L. Kelly, David W. Weller

Bulletin of the Southern California Academy of Sciences

Range and movement data from boat-based photo-identification surveys of Pacific coast common bottlenose dolphins (Tursiops truncatus), carried out over a 6-yr period from 1996 to 2001, were collated and analyzed. Primary data sources were from surveys carried out in four Southern California Bight study areas: Ensenada (12 surveys), San Diego (95 surveys), Santa Monica Bay (170 surveys) and Santa Barbara (61 surveys). Additional data from surveys in Monterey Bay between 1990 and 1993 (84 surveys) were also included in some analyses. Photographic matches between the San Diego, Santa Monica Bay and Santa Barbara study areas ranged from a low of ...


An Evaluation Of The Relative Performance Of Diploid Versus Triploid Brook Trout With Consideration Of The Influence Of Lake Characteristics, Andy Dean 2014 Utah State University

An Evaluation Of The Relative Performance Of Diploid Versus Triploid Brook Trout With Consideration Of The Influence Of Lake Characteristics, Andy Dean

All Graduate Theses and Dissertations

Triploid (sterile) trout potentially offer a more risk-averse option for stocking popular non-native sport fish; however the relative performance (e.g., survival and growth) of triploid versus diploid fish in natural settings is not well understood. I evaluated the relative performance of triploid versus diploid brook trout (Salvelinus fontinalis) stocked in high mountain Uinta lakes in response to food availability and lake morphology. I chose a set of 9 lakes that included a range of elevation and lake morphology. I observed no difference in CPUE or relative weight (Wr) of both types of trout in all lakes. Food availability ...


The Role Of Nitrogen And Phosphorus In The Growth, Toxicity, And Distribution Of The Toxic Cyanobacteria, Microcystis Aeruginosa, James Parrish 2014 University of San Francisco

The Role Of Nitrogen And Phosphorus In The Growth, Toxicity, And Distribution Of The Toxic Cyanobacteria, Microcystis Aeruginosa, James Parrish

Master's Projects

Microcystis aeruginosa is among the most common harmful algal-blooming species in the world. Potent microcystins released by M. aeruginosa have been linked to liver failure and death in aquatic mammals, like the endangered California sea otter, and provide a serious public health risk to humans. Once characterized as a freshwater problem, M. aeruginosa is expanding on a global scale, making persistent returns in freshwater, brackish, and coastal marine ecosystems. Though commonly observed dominating aquatic ecosystems in low N:P atomic ratios less than 44:1, the reliability of N:P ratios as a tool for managing and predicting M. aeruginosa ...


A Longitudinal View Of Primate Life In Two American Laboratories, Jonathan Balcombe 2014 Humane Society Institute for Science and Policy

A Longitudinal View Of Primate Life In Two American Laboratories, Jonathan Balcombe

Animal Research, Testing, and Experimentation

If representative of other facilities, our findings uncover serious welfare concerns for the wellbeing of primates kept in American research facilities. These animals face regular or chronic sources of pain and distress including noxious experimental and non‐experimental events and illness and injury; and severe and prolonged social disruptions. Pain relief is meager by comparison to that normally provided to humans, despite legislative requirements to minimize pain and distress and assume similarity to humans in terms of ability to experience pain and distress. Living environments are usually confinement indoors to a metal cage, often alone, and often with a minimum ...


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