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Exposure Of U.S. National Parks To Land Use And Climate Change 1900-2100, Andrew J. Hansen, Cory Davis, Jessica Haas, David M. Theobald, John E. Gross, William B. Monahan, Tom Olliff, Steven W. Running Apr 2014

Exposure Of U.S. National Parks To Land Use And Climate Change 1900-2100, Andrew J. Hansen, Cory Davis, Jessica Haas, David M. Theobald, John E. Gross, William B. Monahan, Tom Olliff, Steven W. Running

Ecosystem and Conservation Sciences Faculty Publications

Many protected areas may not be adequately safeguarding biodiversity from human activities on surrounding lands and global change. The magnitude of such change agents and the sensitivity of ecosystems to these agents vary among protected areas. Thus, there is a need to assess vulnerability across networks of protected areas to determine those most at risk and to lay the basis for developing effective adaptation strategies. We conducted an assessment of exposure of U.S. National Parks to climate and land use change and consequences for vegetation communities. We first defined park protected-area centered ecosystems (PACEs) based on ecological principles. We then …


Growing Pains Or Opportunities? A Customer Survey Of Three Farmers' Markets In One Rural Community, Randall K. Wilson, Paul A. Di Salvo, Claire E. Quinn, Suzanne T. Englot, Julia P. Mitchell Apr 2014

Growing Pains Or Opportunities? A Customer Survey Of Three Farmers' Markets In One Rural Community, Randall K. Wilson, Paul A. Di Salvo, Claire E. Quinn, Suzanne T. Englot, Julia P. Mitchell

Environmental Studies Faculty Publications

The continued growth of farmers' markets is presenting new challenges to Extension. As the number of markets expands, how can Extension help those in the same community work together for mutual benefit? The study reported here examined similarities and differences among customers attending three different farmers' markets within a single locality in Gettysburg, Pennsylvania. Based on 370 customer surveys, study results underscore the diversity of markets operating within the same community and provide insights into ways Extension might assist markets to work together to expand their shared customer base, increase revenues, and better serve local residents.


Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2012, Daniel M. Dauer, Todd A. Egerton, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Cindy Johnson Apr 2014

Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2012, Daniel M. Dauer, Todd A. Egerton, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Cindy Johnson

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 …


Demographic Survey Of The Sohisika (Schizolaena Tampoketsana) At Ankafobe, Madagascar, James Lucas Apr 2014

Demographic Survey Of The Sohisika (Schizolaena Tampoketsana) At Ankafobe, Madagascar, James Lucas

Independent Study Project (ISP) Collection

No abstract provided.


Pollution In Stone Town’S Coastal Waters: An Assessment Of Environmental Influences On Fecal Contamination, Socorro Lopez Apr 2014

Pollution In Stone Town’S Coastal Waters: An Assessment Of Environmental Influences On Fecal Contamination, Socorro Lopez

Independent Study Project (ISP) Collection

Urbanized areas in Tanzania, including Zanzibar Town on Unguja, are struggling to deal with the large amount of waste generated by growing populations and increasing tourist industries. In 2010, the waters surrounding Stone Town, a subsection of Zanzibar Town, were found to be highly polluted by fecal waste. This study attempted to determine whether pollution has lessened or worsened in the past four years. Furthermore, environmental components of the coastal area, particularly tides, were tested in order to determine whether they had an impact on pollution in the waters. Using the membrane filtration method, mean enterococci were quantified in two …


Mama Nyani: A Study Of The Correlation Of Behaviors And Habitat In Papio Anubis, Madison Beran Apr 2014

Mama Nyani: A Study Of The Correlation Of Behaviors And Habitat In Papio Anubis, Madison Beran

Independent Study Project (ISP) Collection

As the population in Tanzania continues to grow more people are in search of jobs. In Northern Tanzania a village named Mto Wa Mbu is conveniently located directly adjacent to Lake Manyara National Park. With its good location and weather for crops, many people have moved there in hopes to earn some money from the 1 million tourists that visit Tanzania per year. As more people move to Mto Wa Mbu the pressure between animals and the people has increased. With the national park directly across the street from housing both animals and people can easily access each other’s homes. …


Pollution In Stone Town’S Coastal Waters: An Assessment Of Environmental Influences On Fecal Contamination, Socorro Lopez Apr 2014

Pollution In Stone Town’S Coastal Waters: An Assessment Of Environmental Influences On Fecal Contamination, Socorro Lopez

Independent Study Project (ISP) Collection

Urbanized areas in Tanzania, including Zanzibar Town on Unguja, are struggling to deal with the large amount of waste generated by growing populations and increasing tourist industries. In 2010, the waters surrounding Stone Town, a subsection of Zanzibar Town, were found to be highly polluted by fecal waste. This study attempted to determine whether pollution has lessened or worsened in the past four years. Furthermore, environmental components of the coastal area, particularly tides, were tested in order to determine whether they had an impact on pollution in the waters. Using the membrane filtration method, mean enterococci were quantified in two …


The Invading Fly: Innovative Pest Management Solutions For Control Of Bactrocera Invadens In Pemba, Zanzibar, Mccall Calvert, Lindsay Gucker Apr 2014

The Invading Fly: Innovative Pest Management Solutions For Control Of Bactrocera Invadens In Pemba, Zanzibar, Mccall Calvert, Lindsay Gucker

Independent Study Project (ISP) Collection

An integrated pest management study was conducted targeting the invasive fruit fly, Bactrocera invadens, on the island of Pemba, Zanzibar. Male annihilation technique (MAT) traps were set in geographically dispersed sites featuring mango fruit hosts. Three locally sourced essential oils,eucalyptus citriodora, clove and lemongrass were tested against the standard attractant methyl eugenol. Rainfall quantities at each site were collected and interviews with local farmers were conducted on the subject of B. invadens infestation and management. Over the course of the two week study, April 2nd to April 18th, 2014, methyl eugenol baited traps had an …


The Status Of Coastal Birds On Uzi Island: A Coastal Survey Of Birds And Their Interactions With Fishermen And Seaweed Farmers, Anna Curtis-Heald Apr 2014

The Status Of Coastal Birds On Uzi Island: A Coastal Survey Of Birds And Their Interactions With Fishermen And Seaweed Farmers, Anna Curtis-Heald

Independent Study Project (ISP) Collection

Birds are useful environmental indicators and play important roles in the lives of people. A survey of coastal birds was completed around the shores of Uzi Island, Zanzibar. Intertidal flats surveyed at low tide proved to be the most diverse. Mangrove habitat surveyed at high tide was less diverse, yet a mangrove island hosted an abundance of roosting birds.

Although the coastal bird species found on Uzi are of “Least Concern” according to IUCN ratings, conservation of bird habitat, such as mangroves, is a vital step in maintaining biodiversity. Human subjects reported that fishermen and seaweed farmers do not disturb …


From Holy To Holistic: Working Towards Integrated Management Of The Bagmati River Corridor, Lauren Platman Apr 2014

From Holy To Holistic: Working Towards Integrated Management Of The Bagmati River Corridor, Lauren Platman

Independent Study Project (ISP) Collection

The Bagmati and its tributaries have been an integral part of the Kathmandu Valley civilization. The river not only became a source of sustenance for the Valley's population but also gained religious-cultural significance. However, rapid urbanization and increasing industrial activities have transformed this once pristine river into an open sewer. Governmental organizations, NGOs, and community members are working towards improving the conditions of the Bagmati River through restoration projects and public awareness campaigns. Because of the large number of actors, collaboration on projects is vital in order to avoid duplication or conflict. After nearly thirty years of failed restoration projects …


Trail Degradation In Parque Internacional La Amistad: An Intersection Of Design, Management And Use, Jordan Stark Apr 2014

Trail Degradation In Parque Internacional La Amistad: An Intersection Of Design, Management And Use, Jordan Stark

Independent Study Project (ISP) Collection

National parks are created and used for a variety of purposes but are primarily important for the conservation of natural resources and use by visitors. While park use is meant to be non-destructive, human interaction causes changes in ecosystems, leading to conflicts between these goals. Here, I examine the causes of trail degradation and impacts on surrounding forests in Parque Internacional la Amistad (PILA), Panama. This park is a world heritage site with the primary goal of preserving some of the world’s most diverse ecosystems including rare and endangered species. However, the park entrance in Las Nubes, Cerro Punta receives …


Effectiveness Of Air Sealing Measures And Other Energy Retrofit Measures In Lafayette Energy Improvement Program, Jia Ye Apr 2014

Effectiveness Of Air Sealing Measures And Other Energy Retrofit Measures In Lafayette Energy Improvement Program, Jia Ye

Open Access Theses

From September 2011 to March 2013, the City of Lafayette, IN implemented Lafayette Improvement Program. The goal of this project was to "increase energy efficiency of existing homes through retrofitting, thereby lowering the costs of home ownership within the Vinton and Glen Acres Neighborhood Target Area (The City of Lafayette, 2011)." Energy audit companies carried out before blower door test and after blower door test to identify air tightness of subjects. This paper finds out there was an improvement in air tightness in the population of 85 houses and the degree of improvement was between 16.85% and 17.85%.

Change point …


Temperature And Relative Humidity Effects On Water Loss And Hemolymph Osmolality Of Littoraria Angulifera (Lamarck, 1822), Phillip J. Rose Apr 2014

Temperature And Relative Humidity Effects On Water Loss And Hemolymph Osmolality Of Littoraria Angulifera (Lamarck, 1822), Phillip J. Rose

Theses and Dissertations - UTB/UTPA

Desiccation stress is considered to be one of the more significant determining factors that influence how organisms are distributed in the marine littoral. Gastropods living above the high tide mark, referred to as eulittoral fringe gastropods are not wetted as regularly and face unpredictable and prolonged periods of emersion. Consequently, adaptations displayed by eulittoral fringe gastropods are aimed at minimizing water loss and surviving prolonged periods of desiccation stress. Littoraria angulifera, is a tropically distributed marine eulittoral fringe gastropod. Because L. angulifera spends a majority of its time emersed there was interest in studying how the weight loss and hemolymph …


The Effects Of Predator Cues On Vertical Foraging Habits In The White-Footed Mouse (Peromyscus Leucopus), Caitlin Stark Apr 2014

The Effects Of Predator Cues On Vertical Foraging Habits In The White-Footed Mouse (Peromyscus Leucopus), Caitlin Stark

All Student Theses and Dissertations

Predation risk can have a strong influence on foraging behavior. I hypothesized that 1) Peromyscus leucopus would climb trees and forage at greater heights if there is coyote urine present and 2) if there are owl pellets present, P. leucopus would avoid foraging at that tree. To explore these hypotheses, giving-up densities (GUDs) were measured by using foraging trays mounted on trees in an oak forest located in eastern Will County Illinois. Data was analyzed using repeated measures MANOVA. Scent was the only significant difference during owl pellet treatments (P=0.0471, df=1). A significant difference was found between scent (P=0.0183, df=1), …


Determination Of The Ecological Condition Of Benthic Communities Affected By Polycyclic Aromatic Hydrocarbons In The Elizabeth River, Chesapeake Bay, Usa, Adam M. Webb Apr 2014

Determination Of The Ecological Condition Of Benthic Communities Affected By Polycyclic Aromatic Hydrocarbons In The Elizabeth River, Chesapeake Bay, Usa, Adam M. Webb

Biological Sciences Theses & Dissertations

The Southern Branch of the Elizabeth River, a tributary of Chesapeake Bay, has historically been polluted with hydrocarbon based industrial by-products. My study compared benthic community condition from two locations in the Southern Branch: the subtidal region near Money Point, historically affected by pollution of polycyclic aromatic hydrocarbons (PAHs), to a subtidal region near Blows Creek on the opposite shore that is putatively designated as unimpacted by P AH contamination. Samples from both study sites in the Southern Branch were compared to the benthic community condition of samples from the same habitat type designations collected as part of the Chesapeake …


Benthic And Planktonic Microalgal Community Structure And Primary Productivity In Lower Chesapeake Bay, Matthew Reginald Semcheski Apr 2014

Benthic And Planktonic Microalgal Community Structure And Primary Productivity In Lower Chesapeake Bay, Matthew Reginald Semcheski

Biological Sciences Theses & Dissertations

Microalgal populations are trophically important to a variety of micro- and macroheterotrophs in marine and estuarine systems. In Chesapeake Bay, microalgae facilitate the survival and development of ecologically and economically relevant fauna, including shellfish and finfish populations. While regarded as significant components of coastal environments, microphytobenthic communities are historically understudied. In Chesapeake Bay, the importance of phytoplankton to the ecosystem is understood, but the contribution of microphytobenthos remains unclear. This project surveys intertidal microphytobenthic communities, in relation to phytoplankton communities, around lower Chesapeake Bay describing the taxonomic makeup of these populations, coupled with quantification of cell abundance, biomass, and primary …


The Fierce Green Fire: Vol. 4 Issue 18, Wofford College Environmental Studies Program Mar 2014

The Fierce Green Fire: Vol. 4 Issue 18, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Lead (Pb) Contamination Of Water Drawn From Pitcher Pumps In Eastern Madagascar, David Bradlee Akers Mar 2014

Lead (Pb) Contamination Of Water Drawn From Pitcher Pumps In Eastern Madagascar, David Bradlee Akers

USF Tampa Graduate Theses and Dissertations

Access to safe water supply--a major determinant of public health--is less than 50% in Madagascar, and access to piped, treated water remains out of reach financially for many in the urban and peri-urban areas where available. The Self-supply option of the Pitcher Pump has been meeting the need for household water in coastal areas of Madagascar since the early 1960s and has proven a sustainable option for many. These pumps make use of leaded components in the construction, however, which may pose a health risk for heavy metal intoxication and therefore cause the water to be unsafe for drinking and …


Assessing The Homogenization Of Urban Land Management With An Application To Us Residential Lawn Care, Colin Polsky, J. Morgan Grove, Chris Knudson, Peter M. Groffman, Neil D. Bettez, Jeannine Cavender-Bares, Sharon J. Hall, James B. Heffernan, Sarah E. Hobbie, Kelli L. Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Laura A. Ogden, Jarlath O'Neil-Dunne, Diane E. Pataki, Rinku Roy Chowdhury, Meredith K. Steele Mar 2014

Assessing The Homogenization Of Urban Land Management With An Application To Us Residential Lawn Care, Colin Polsky, J. Morgan Grove, Chris Knudson, Peter M. Groffman, Neil D. Bettez, Jeannine Cavender-Bares, Sharon J. Hall, James B. Heffernan, Sarah E. Hobbie, Kelli L. Larson, Jennifer L. Morse, Christopher Neill, Kristen C. Nelson, Laura A. Ogden, Jarlath O'Neil-Dunne, Diane E. Pataki, Rinku Roy Chowdhury, Meredith K. Steele

Environmental Science and Management Faculty Publications and Presentations

Changes in land use, land cover, and land management present some of the greatest potential global environmental challenges of the 21st century. Urbanization, one of the principal drivers of these transformations, is commonly thought to be generating land changes that are increasingly similar. An implication of this multiscale homogenization hypothesis is that the ecosystem structure and function and human behaviors associated with urbanization should be more similar in certain kinds of urbanized locations across biogeophysical gradients than across urbanization gradients in places with similar biogeophysical characteristics. This paper introduces an analytical framework for testing this hypothesis, and applies the framework …


Sustainable Energy And Nutrient Recovery From Swine Waste, Adib Amini Mar 2014

Sustainable Energy And Nutrient Recovery From Swine Waste, Adib Amini

USF Tampa Graduate Theses and Dissertations

Swine production represents approximately 40% of the world's meat production, and swine wastes contain high concentrations of organic matter, nitrogen (N) and phosphorus (P). Swine production is intensifying as meat demand increases and concentrated animal feeding operations (CAFOs) are becoming increasingly common, making it difficult to treat the waste generated. A system for holistic treatment of swine waste produced in CAFOs was investigated in this study that sustainably generates energy and recovers N and P as saleable fertilizers. The system uses anaerobic digestion (AD) for methane production and solids stabilization, followed by precipitation of struvite (MgNH4PO4*6H2O) and recovery of N …


Co2 Recycling Using Microalgae For The Production Of Fuels, Michael H. Wilson, John Groppo, Andrew Placido, S. Graham, S. A. Morton Iii, Eduardo Santillan-Jimenez, Aubrey Shea, Mark Crocker, Czarena Crofcheck, Rodney Andrews Mar 2014

Co2 Recycling Using Microalgae For The Production Of Fuels, Michael H. Wilson, John Groppo, Andrew Placido, S. Graham, S. A. Morton Iii, Eduardo Santillan-Jimenez, Aubrey Shea, Mark Crocker, Czarena Crofcheck, Rodney Andrews

Center for Applied Energy Research Faculty and Staff Publications

CO2 capture and recycle using microalgae was demonstrated at a coal-fired power plant (Duke Energy’s East Bend Station, Kentucky). Using an in-house designed closed loop, vertical tube photobioreactor, Scenedesmus acutus was cultured using flue gas as the CO2 source. Algae productivity of 39 g/(m2 day) in June–July was achieved at significant scale (18,000 L), while average daily productivity slightly in excess of 10 g/(m2 day) was demonstrated in the month of December. A protocol for low-cost algae harvesting and dewatering was developed, and the conversion of algal lipids—extracted from the harvested biomass—to diesel-range hydrocarbons via catalytic …


The Fierce Green Fire: Vol. 4 Issue 17, Wofford College Environmental Studies Program Mar 2014

The Fierce Green Fire: Vol. 4 Issue 17, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Lifeblood Of The Earth: Nuwuvi (Southern Paiute) Hydrological Knowledge And Perceptions Of Restoration In Two Southern Nevada Protected Areas, Kendra Lesley Wendel Mar 2014

Lifeblood Of The Earth: Nuwuvi (Southern Paiute) Hydrological Knowledge And Perceptions Of Restoration In Two Southern Nevada Protected Areas, Kendra Lesley Wendel

Dissertations and Theses

In the arid landscapes of the southern Great Basin and northern Mojave Desert, issues surrounding water resource management are often politically contentious. Nuwuvi (Southern Paiute) have known and managed these resources for thousands of years prior to Euro-American arrival in the region. A variety of factors, including federal policies that resulted in the creation of reservations and forced placement in boarding schools, as well as contemporary resource commodification, have influenced Nuwuvi knowledge and practice.

In this thesis, I examined the character of Nuwuvi ethnohydrological knowledge, including management knowledge, of two protected areas: Spring Mountains National Recreation Area (SMNRA), managed by …


Coastal And Ocean Economic Summaries Of The Coastal States 2014, Pat Johnston Mar 2014

Coastal And Ocean Economic Summaries Of The Coastal States 2014, Pat Johnston

Publications

The following summaries of the ocean and coastal economies were prepared by the National Ocean Economics Program as a companion the State of the U.S. Ocean and Coastal Economies 2014. The U.S. report, its appendices, and these state summary reports are available on the NOEP website at www.OceanEconomics.org/download.


The Fierce Green Fire: Vol. 4 Issue 16, Wofford College Environmental Studies Program Mar 2014

The Fierce Green Fire: Vol. 4 Issue 16, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Similar Resilience Attributes In Lakes With Different Management Practices, Didier L. Baho, Stina Drakare, Richard K. Johnson, Craig R. Allen, David G. Angeler Mar 2014

Similar Resilience Attributes In Lakes With Different Management Practices, Didier L. Baho, Stina Drakare, Richard K. Johnson, Craig R. Allen, David G. Angeler

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Liming has been used extensively in Scandinavia and elsewhere since the 1970s to counteract the negative effects of acidification. Communities in limed lakes usually return to acidified conditions once liming is discontinued, suggesting that liming is unlikely to shift acidified lakes to a state equivalent to pre-acidification conditions that requires no further management intervention. While this suggests a low resilience of limed lakes, attributes that confer resilience have not been assessed, limiting our understanding of the efficiency of costly management programs. In this study, we assessed community metrics (diversity, richness, evenness, biovolume), multivariate community structure and the relative resilience of …


The Fierce Green Fire: Vol. 4 Issue 15, Wofford College Environmental Studies Program Mar 2014

The Fierce Green Fire: Vol. 4 Issue 15, Wofford College Environmental Studies Program

The Fierce Green Fire

No abstract provided.


Productivity And Carbon Dioxide Exchange Of Leguminous Crops: Estimates From Flux Tower Measurements, Tagir Gilmanov, John M. Baker, Carl J. Bernacchi, David P. Billesbach, George G. Burba, Saulo Castro, Jiquan Chen, Werner Eugster, Marc L. Fischer, John A. Gamon, Maheteme T. Gebremedhin, Aaron J. Glenn, Timothy J. Griffis, Jerry L. Hatfield, Mark W. Heuer, Daniel M. Howard, Monique Y. Leclerc, Henry W. Loescher, Oliver Marloie, Tilden P. Meyers, Albert Olioso, Rebecca L. Phillips, John H. Prueger, R. Howard Skinner, Andrew E. Suyker, Mario Tenuta, Bruce K. Wylie Mar 2014

Productivity And Carbon Dioxide Exchange Of Leguminous Crops: Estimates From Flux Tower Measurements, Tagir Gilmanov, John M. Baker, Carl J. Bernacchi, David P. Billesbach, George G. Burba, Saulo Castro, Jiquan Chen, Werner Eugster, Marc L. Fischer, John A. Gamon, Maheteme T. Gebremedhin, Aaron J. Glenn, Timothy J. Griffis, Jerry L. Hatfield, Mark W. Heuer, Daniel M. Howard, Monique Y. Leclerc, Henry W. Loescher, Oliver Marloie, Tilden P. Meyers, Albert Olioso, Rebecca L. Phillips, John H. Prueger, R. Howard Skinner, Andrew E. Suyker, Mario Tenuta, Bruce K. Wylie

School of Natural Resources: Faculty Publications

Net CO2 exchange data of legume crops at 17 flux tower sites in North America and three sites in Europe representing 29 site-years of measurements were partitioned into gross photosynthesis and ecosystem respiration by using the nonrectangular hyperbolic lightresponse function method. The analyses produced net CO2 exchange data and new ecosystem-scale ecophysiological parameter estimates for legume crops determined at diurnal and weekly time steps. Dynamics and annual totals of gross photosynthesis, ecosystem respiration, and net ecosystem production were calculated by gap filling with multivariate nonlinear regression. Comparison with the data from grain crops obtained with the same method …


Comparative Efficiency And Driving Range Of Light- And Heavy-Duty Vehicles Powered With Biomass Energy Stored In Liquid Fuels Or Batteries, Mark Laser, Lee R. R. Lynd Mar 2014

Comparative Efficiency And Driving Range Of Light- And Heavy-Duty Vehicles Powered With Biomass Energy Stored In Liquid Fuels Or Batteries, Mark Laser, Lee R. R. Lynd

Dartmouth Scholarship

This study addresses the question, "When using cellulosic biomass for vehicular transportation, which field-to-wheels pathway is more efficient: that using biofuels or that using bioelectricity?" In considering the question, the level of assumed technological maturity significantly affects the comparison, as does the intended transportation application. Results from the analysis indicate that for light-duty vehicles, over ranges typical in the United States today (e.g., 560-820 miles), field-to-wheels performance is similar, with some scenarios showing biofuel to be more efficient, and others indicating the two pathways to be essentially the same. Over the current range of heavy-duty vehicles, the field-to-wheels efficiency is …


Nestling Sex Ratios Do Not Support Long-Term Parity In Two Species With Different Life-History Strategies, Noah G. Perlut, Steven E. Travis, Catherine A. Dunbar, Allan M. Strong, Derek M. Wright Mar 2014

Nestling Sex Ratios Do Not Support Long-Term Parity In Two Species With Different Life-History Strategies, Noah G. Perlut, Steven E. Travis, Catherine A. Dunbar, Allan M. Strong, Derek M. Wright

Environmental Studies Faculty Publications

To maximize fitness, breeding adults may respond to environmental processes by adjusting their progeny’s sex ratios. R. A. Fisher in 1930 hypothesized that frequency-dependent selection would result in equal investment in sons and daughters over the long term, yielding a balanced sex ratio if the costs of raising a son and daughter are equal. Diverse hypotheses have tried to explain population and brood-by-brood deviations from this mean as well as annual variation by focusing on adult sex ratios, resources, abiotic conditions, and female and male quality. We collected data in 2002-2010 to explore population-level variation in nestling sex ratios in …