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Full-Text Articles in Natural Resource Economics

Plains Zebra (Equus Quagga) Behaviour In A Restored Population Reveals Seasonal Resource Limitations, Charli De Vos, Alison J. Leslie, Jason I. Ransom Jan 2020

Plains Zebra (Equus Quagga) Behaviour In A Restored Population Reveals Seasonal Resource Limitations, Charli De Vos, Alison J. Leslie, Jason I. Ransom

United States National Park Service: Publications

A once abundant species, plains zebra (Equus quagga), is declining across much of sub-Saharan Africa. Reintroduction efforts at Majete Wildlife Reserve, Malawi, have resulted in rapid population increases, but little is known about how such populations resemble natural populations socially or behaviourally, and what those attributes may reveal about restoration success. Incorporating behavioural knowledge into conservation efforts is an important tool for managing the effects of habitat fragmentation and resource competition. The aim of this study was to quantify the daylight time budget of both family and bachelor bands of reintroduced plains zebra to determine if such behaviours …


Predicting Livestock Depredation Risk By African Lions (Panthera Leo) In A Multi-Use Area Of Northern Tanzania, K. Beattie, E. R. Olson, B. Kissui, A. Kirschbaum, C. Kiffner Jan 2020

Predicting Livestock Depredation Risk By African Lions (Panthera Leo) In A Multi-Use Area Of Northern Tanzania, K. Beattie, E. R. Olson, B. Kissui, A. Kirschbaum, C. Kiffner

United States National Park Service: Publications

Human-wildlife conflicts, especially those involving large carnivores, are of global conservation and livelihood concern and require effective and locally-adapted prevention measures. Risk of lion attack on livestock (i.e. depredation) may vary seasonally and may be associated with variation in wild prey abundance or landscape characteristics. To test these competing hypotheses, we used a resource selection approach, and determined whether prey catchability (indicated by geo-spatial variables), or prey availability (indicated by modeled abundance recorded via camera traps) explained spatial and seasonal variation in livestock depredation risk by African lions on Manyara Ranch Conservancy, a multi-use area in northern Tanzania. Seasonal variation …


An Exploratory Study On The Managerial Competencies Of First-Line Managers In A Philippine University, Alyssa Kaye S. Mojar, Dinah Pura T. Depositario Jan 2020

An Exploratory Study On The Managerial Competencies Of First-Line Managers In A Philippine University, Alyssa Kaye S. Mojar, Dinah Pura T. Depositario

Journal of Economics, Management and Agricultural Development

Faculty and researchers, mostly well-trained, usually fill managerial positions at universities. Still, they do not have formal management training. This qualitative study examined the managerial competencies of 11 university firstline managers. Using Kurz and Bartram’s Great Eight Competency Theory (2002) for the thematic analysis of the interview transcripts, most of the respondents exhibited all eight competencies. However, they differed in terms of manifestations. A typology of academic administrators was developed based on the eight competencies, namely: (1) delegator, (2) accommodator, (3) director, and (4) initiator. Further quantitative research is recommended to refine this typology. Likewise, to develop current and potential …


Intercropping For Water Conservation: Environmental And Economic Implications Of A Sustainable Farming Practice In California's Central Valley, Sophie Baker Jan 2020

Intercropping For Water Conservation: Environmental And Economic Implications Of A Sustainable Farming Practice In California's Central Valley, Sophie Baker

Scripps Senior Theses

California’s agricultural sector is the biggest water consumer in the state and faces intense pressure to reduce its overall water usage. Industrialized monoculture systems dominate the industry and often disregard long-term environmental and economic externalities for short-term profit maximization. To maintain longstanding food security and economic stability as well as protect the state’s water supply, it is critical that these systems transition to more sustainable and resilient production mechanisms. As an alternative to monoculture, intercropping affords greater potential to conserve water, protect soil quality, and increase crop yields, among other metrics of sustainability. However, there has been much controversy over …


Family Forest Owners Satisfaction With Timber Transactions, Jeffrey M. Lee Jan 2020

Family Forest Owners Satisfaction With Timber Transactions, Jeffrey M. Lee

Graduate Theses, Dissertations, and Problem Reports (ETD)

Forest industries in the eastern U.S. rely heavily on family forest owners to supply fiber needs for their mills. As of 2017, 79 percent of West Virginia is classified as forestland and of this roughly 86.5 percent is privately owned. With such a heavy reliance on wood from private forest lands, family forest owner satisfaction is extremely important if companies want to continue harvesting or working with these landowners in the future.

Timber transactions are complex. No two timber transactions are exactly the same. They often involve many different parties apart from the landowner. Site conditions, land cover, and landowner …


Ecosystem Services And Disservices Of Mangrove Forests And Salt Marshes, Daniel A. Friess, Erik S. Yando, Jahson B. Alemu I, Lynn-Wei Wong, Sasha D. Soto, Natasha Bhatia, S. J. Hawkins (Ed.), A. L. Allcock (Ed.), A. E. Bates (Ed.), A.J. Evans (Ed.), L. B. Firth (Ed.), C. D. Mcquaid (Ed.), B. D. Russell (Ed.), I. P. Smith (Ed.), S. E. Swearer (Ed.), P. A. Todd (Ed.) Jan 2020

Ecosystem Services And Disservices Of Mangrove Forests And Salt Marshes, Daniel A. Friess, Erik S. Yando, Jahson B. Alemu I, Lynn-Wei Wong, Sasha D. Soto, Natasha Bhatia, S. J. Hawkins (Ed.), A. L. Allcock (Ed.), A. E. Bates (Ed.), A.J. Evans (Ed.), L. B. Firth (Ed.), C. D. Mcquaid (Ed.), B. D. Russell (Ed.), I. P. Smith (Ed.), S. E. Swearer (Ed.), P. A. Todd (Ed.)

Biological Sciences Faculty Publications

Coastal wetlands such as mangrove forests and salt marshes provide a range of important benefits to people, broadly defined as ecosystem services. These include provisioning services such as fuelwood and food, regulating services such as carbon sequestration and wave attenuation, and various tangible and intangible cultural services. However, strong negative perceptions of coastal wetlands also exist, often driven by the perceived or actual ecosystem disservices that they also produce. These can include odour, a sense of danger, and their real or perceived role in vector and disease transmission (e.g. malaria). This review provides an introduction to the ecosystem services and …


Direct And Indirect Effects Of Temperature And Prey Abundance On Bald Eagle Reproductive Dynamics, Joshua H. Schmidt, Judy Putera, Tammy L. Wilson Dec 2019

Direct And Indirect Effects Of Temperature And Prey Abundance On Bald Eagle Reproductive Dynamics, Joshua H. Schmidt, Judy Putera, Tammy L. Wilson

United States National Park Service: Publications

Understanding the mechanisms by which populations are regulated is critical for predicting the effects of large-scale perturbations. While discrete mortality events provide clear evidence of direct impacts, indirect pathways are more difficult to assess but may play important roles in population and ecosystem dynamics. Here, we use multi-state occupancy models to analyze a long-term dataset on nesting bald eagles in south-central Alaska with the goal of identifying both direct and indirect mechanisms influencing reproductive output in this apex predator. We found that the probabilities of both nest occupancy and success were higher in the portion of the study area where …


Plant Community Composition And Structure Monitoring At Wind Cave National Park, 2019 Data Report, Theresa L. Schaffner, Daniel J. Swanson, Stephanie L. Rockwood Dec 2019

Plant Community Composition And Structure Monitoring At Wind Cave National Park, 2019 Data Report, Theresa L. Schaffner, Daniel J. Swanson, Stephanie L. Rockwood

United States National Park Service: Publications

Abstract

This report presents the results of the Northern Great Plains Inventory and Monitoring Network (NGPN) and Northern Great Plains Fire Ecology Program (NGPFire) vegetation monitoring at Wind Cave National Park (WICA) in 2019. This was the ninth year of combined monitoring efforts.

Crew members from NGPN visited 18 long-term monitoring plots to collect data representing the plant communities at WICA. The NGPFire program collected pre- and post-burn data from an additional 37 plant community and forest structure monitoring plots. This work is part of a long-term monitoring effort designed to evaluate the condition of the vegetation community and understand …


Vegetation Classification And Mapping, Missouri National Recreational River, Tom Baldvins, Matt Ley, David Jones, Joe Stevens, Hannah Pilkington Dec 2019

Vegetation Classification And Mapping, Missouri National Recreational River, Tom Baldvins, Matt Ley, David Jones, Joe Stevens, Hannah Pilkington

United States National Park Service: Publications

Executive Summary

The vegetation inventory project at Missouri National Recreational River (MNRR) classified and mapped vegetation within the park administrative boundary and estimated thematic map accuracy quantitatively. The project was conducted over a four year period from the summer of 2015 to the winter of 2019.

The project follows guidance provided by the National Park Service (NPS) Vegetation Mapping Inventory (VMI) Program. The overall process includes initial planning and scoping, imagery procurement, field data collection, data analysis, imagery interpretation and classification, and accuracy assessment. The initial planning and scoping meetings to support study plan development took place in December, 2009, …


Natural Resource Condition Assessment, Homestead National Monument Of America, David S. Jones, Roy Cook, John Sovell, Christopher Herron, Jay Benner, Karin Decker, Andrew Beavers, Johannes Beebee, David Weinzimmer Dec 2019

Natural Resource Condition Assessment, Homestead National Monument Of America, David S. Jones, Roy Cook, John Sovell, Christopher Herron, Jay Benner, Karin Decker, Andrew Beavers, Johannes Beebee, David Weinzimmer

United States National Park Service: Publications

Executive Summary

The National Park Service (NPS) Natural Resource Condition Assessment (NRCA) Program administered by the NPS Water Resources Division evaluates current conditions for important natural resources and resource indicators using primarily existing information and data. NRCAs also report on trends in resource condition when possible, identify critical data gaps, and characterize a general level of confidence for study findings. This NRCA complements historic resource assessments, is multi-disciplinary in scope, employs a hierarchical indicator framework, identifies and develops reference conditions/values for comparison against current conditions, and emphasizes spatial evaluation of conditions and GIS (map) products.

Congress established the Homestead National …


Plant Community Composition And Structure Monitoring At Agate Fossil Beds National Monument, 2019 Data Report, Molly B. Davis Dec 2019

Plant Community Composition And Structure Monitoring At Agate Fossil Beds National Monument, 2019 Data Report, Molly B. Davis

United States National Park Service: Publications

Abstract

This report presents the results of vegetation monitoring efforts in 2019 at Agate Fossil Beds National Monument (AGFO) by the Northern Great Plains Inventory and Monitoring Network (NGPN) and the Northern Great Plains Fire Ecology Program (NGPFire). This was the ninth year of combined monitoring efforts.

In 2019, crew members from NGPN visited 6 long-term plant community monitoring (PCM) plots to collect data on the upland mixed-grass prairie plant communities at AGFO. This work is part of a long-term monitoring program established to better understand the condition of the vegetation community and how it changes over time. NGPN staff …


Interpreting Potential Groundwater Policies Through Modeling Of Market And Non-Market Benefits And Costs, Grant H. West Dec 2019

Interpreting Potential Groundwater Policies Through Modeling Of Market And Non-Market Benefits And Costs, Grant H. West

Graduate Theses and Dissertations

Current policies leveraging financial incentives and improved irrigation efficiency to mitigate groundwater scarcity have not proven to curtail trends of resource depletion. Groundwater benefits cannot be appropriately valued solely on market forces, and so deeper policy consideration is warranted under a framework that considers the importance of groundwater across all its values to society. Understanding time preferences for groundwater management and preferences for alternative policies is vital to inform efficient policies. Furthermore, climate change remains politically controversial yet has important consequences for critical groundwater resources and their sustainable long-term management. Proliferating policy narratives concerning climate change could influence the way …


Material And Seismic Assessment Of The Great House At Casa Grande Ruins National Monument, Arizona, Douglas W. Porter, Anjali Mehrotra, Matthew J. Dejong, Angelyn Bass, Matthew Guebard, John Ochsendorf Nov 2019

Material And Seismic Assessment Of The Great House At Casa Grande Ruins National Monument, Arizona, Douglas W. Porter, Anjali Mehrotra, Matthew J. Dejong, Angelyn Bass, Matthew Guebard, John Ochsendorf

United States National Park Service: Publications

The authors characterized earthen wall materials and plasters in a mid-fourteenth-century Hohokam great house at Casa Grande Ruins National Monument (Arizona) and assessed the seismic susceptibility of its puddled earth walls. Characterization included determining the microstructure, microcomposition, porosity, aggregate mineralogy, and identification of phases in the binding matrix for each of 36 samples and reconstructing plaster technologies, including material selection, preparation, and application sequences. Findings support the ideas that earthen materials were manipulated to optimize their performance to suit the unique site conditions and needs of the ancient people using the structure and included finishes that were unusual in southwestern …


Exposure And Potential Effects Of Pesticides And Pharmaceuticals In Protected Streams Of The Us National Park Service Southeast Region, Paul M. Bradley, Kristin M. Romanok, Jeffrey R. Duncan, William A. Battaglin, Jimmy M. Clark, Michelle L. Hladik, Bradley J. Huffman, Luke R. Iwanowicz, Celeste A. Journey, Kelly L. Smalling Nov 2019

Exposure And Potential Effects Of Pesticides And Pharmaceuticals In Protected Streams Of The Us National Park Service Southeast Region, Paul M. Bradley, Kristin M. Romanok, Jeffrey R. Duncan, William A. Battaglin, Jimmy M. Clark, Michelle L. Hladik, Bradley J. Huffman, Luke R. Iwanowicz, Celeste A. Journey, Kelly L. Smalling

United States National Park Service: Publications

Globally, protected areas offer refugia for a broad range of taxa including threatened and endangered species. In the United States (US), the National Park Service (NPS) manages public lands to preserve biodiversity, but increasing park visitation and development of surrounding landscapes increase exposure to and effects from bioactive contaminants. The risk (exposure and hazard) to NPS protected-stream ecosystems within the highly urbanized southeast region (SER) from bioactive contaminants was assessed in five systems based on 334 pesticide and pharmaceutical analytes in water and 119 pesticides in sediment. Contaminant mixtures were common across all sampled systems, with approximately 24% of the …


Satellite-Based Decadal Change Assessments Of Pan-Arctic Environments, Liza K. Jenkins, Tom Barry, Karl R. Bosse, William S. Currie, Tom Christensen, Sara Longan, Robert A. Shuchman, Danielle Tanzer, Jason J. Taylor Nov 2019

Satellite-Based Decadal Change Assessments Of Pan-Arctic Environments, Liza K. Jenkins, Tom Barry, Karl R. Bosse, William S. Currie, Tom Christensen, Sara Longan, Robert A. Shuchman, Danielle Tanzer, Jason J. Taylor

United States National Park Service: Publications

Remote sensing can advance the work of the Circumpolar Biodiversity Monitoring Program through monitoring of satellite-derived terrestrial and marine physical and ecological variables. Standardized data facilitate an unbiased comparison across variables and environments. Using MODIS standard products of land surface temperature, percent snow-covered area, NDVI, EVI, phenology, burned area, marine chlorophyll, CDOM, sea surface temperature, and marine primary productivity, significant trends were observed in almost all variables between 2000 and 2017. Analysis of seasonal data revealed significant breakpoints in temporal trends. Within the terrestrial environment, data showed significant increasing trends in land surface temperature and NDVI. In the marine environment, …


Sustainable Growth Through Value Chain Development In The Blue Economy : A Case Study Of The Port Of Walvis Bay, Tangeni Haimbala Nov 2019

Sustainable Growth Through Value Chain Development In The Blue Economy : A Case Study Of The Port Of Walvis Bay, Tangeni Haimbala

World Maritime University Dissertations

No abstract provided.


Potentials And Challenges For Egypt To Achieve Blue Growth : An Sdg 14 Perspective, Mamdouh Awad Abdelrahman Shahhat Nov 2019

Potentials And Challenges For Egypt To Achieve Blue Growth : An Sdg 14 Perspective, Mamdouh Awad Abdelrahman Shahhat

World Maritime University Dissertations

No abstract provided.


Vegetation Classification And Mapping, Niobrara National Scenic River, Tom Baldvins, Matt Ley, Joe Stevens, David Jones, Hannah Pilkington Nov 2019

Vegetation Classification And Mapping, Niobrara National Scenic River, Tom Baldvins, Matt Ley, Joe Stevens, David Jones, Hannah Pilkington

United States National Park Service: Publications

Executive Summary

The vegetation inventory project at Niobrara National Scenic River (NIOB) classified and mapped vegetation within the park administrative boundary and estimated thematic map accuracy quantitatively. The project was conducted over a four year period from the summer of 2015 to the winter of 2019. Located in north-central Nebraska, approximately 76 miles of the park is designated as a wild and scenic river. The vast majority of land within the NIOB administrative boundary is private or state-owned.

The project follows guidance provided by the National Park Service (NPS) Vegetation Mapping Inventory (VMI) Program. The overall process includes initial planning …


Natural Resource Condition Assessment, Tallgrass Prairie National Preserve, David S. Jones, Roy Cook, John Sovell, Christopher Herron, Jay Benner, Karin Decker, Andrew Beavers, Johannes Beebee, David Weinzimmer, Rob Schorr Nov 2019

Natural Resource Condition Assessment, Tallgrass Prairie National Preserve, David S. Jones, Roy Cook, John Sovell, Christopher Herron, Jay Benner, Karin Decker, Andrew Beavers, Johannes Beebee, David Weinzimmer, Rob Schorr

United States National Park Service: Publications

Executive Summary

The National Park Service (NPS) Natural Resource Condition Assessment (NRCA) Program administered by the NPS Water Resources Division evaluates current conditions for important natural resources and resource indicators using primarily existing information and data. NRCAs also report on trends in resource condition when possible, identify critical data gaps, and characterize a general level of confidence for study findings. This NRCA complements historic resource assessments, is multi-disciplinary in scope, employs a hierarchical indicator framework, identifies and develops reference conditions/values for comparison against current conditions, and emphasizes spatial evaluation of conditions and GIS products.

Created in 1996, Tallgrass Prairie National …


Relationships Between Soil Macroinvertebrates And Nonnative Feral Pigs (Sus Scrofa) In Hawaiian Tropical Montane Wet Forests, Nathaniel H. Wehr, Creighton M. Litton, Noa K. Lincoln, Steven C. Hess Oct 2019

Relationships Between Soil Macroinvertebrates And Nonnative Feral Pigs (Sus Scrofa) In Hawaiian Tropical Montane Wet Forests, Nathaniel H. Wehr, Creighton M. Litton, Noa K. Lincoln, Steven C. Hess

United States National Park Service: Publications

Abstract Nonnative feral pigs (Sus scrofa) are recognized throughout the New World as a highly significant introduced species in terms of ecosystem alteration. Similarly, nonnative soil macroinvertebrates (e.g. earthworms, ground beetles) invade and alter the structure and function of native habitats globally. However, the relationship between feral pigs and soil macroinvertebrates remains largely unknown. This study analyzed relationships between these taxa using nine sites located inside and outside of feral pig management units representing a * 25 year chronosequence of removal in tropical montane wet forests in Hawai‘i. Soil macroinvertebrates were sampled from plots categorized as: actively trampled by feral …


Investing In The New Blue Economy: The Changing Role Of International Development Organizations In Catalyzing Private Sector Investment In Support Of Regional Strategic Action Programmes For The Sustainable Development Of Coasts And Oceans, Ryan Whisnant, Veerle Vandeweerd Oct 2019

Investing In The New Blue Economy: The Changing Role Of International Development Organizations In Catalyzing Private Sector Investment In Support Of Regional Strategic Action Programmes For The Sustainable Development Of Coasts And Oceans, Ryan Whisnant, Veerle Vandeweerd

Journal of Ocean and Coastal Economics

Over the last 20 years, governments sharing common coastal and ocean ecosystems have developed and agreed on concrete regional action programs to stop and, in some cases, reverse a trend of deteriorating coastal and ocean resources. Implementation of these action programs requires significant investments by the public and private sectors alike, with the potential for substantial economic growth and enhanced social well-being. For this to happen, new institutional arrangements, technologies, and financial vehicles and asset classes are needed to mainstream innovative “blue economy” projects that have the potential to transition economies and communities to more sustainable development paths.

This paper …


Blue Economy And Climate Change: Bangladesh Perspective, Subrata Sarker, Firdaus Ara Hussain, Mohammad Assaduzzaman, Pierre Failler Oct 2019

Blue Economy And Climate Change: Bangladesh Perspective, Subrata Sarker, Firdaus Ara Hussain, Mohammad Assaduzzaman, Pierre Failler

Journal of Ocean and Coastal Economics

Blue Economy is related to economic growth through the sustainable utilization of ocean resources with technological inputs to improve livelihoods. Economically important coastal and marine resources are the main components of the Blue Economy for Bangladesh. These resources are categorized into living, non-living, renewable resources and trade and commerce. As Bangladesh is vulnerable to climate change, related extreme events are making the coastal and marine resources vulnerable which may hamper the smooth Blue Economy development in Bangladesh. Climate change extreme events include warming trend, cyclone, sea level rise, droughts, erosion, tidal surge, saline water intrusion, flood, change in precipitation trend …


Juvenile Hawksbill Residency And Habitat Use Within A Caribbean Marine Protected Area, Thomas H. Selby, Kristen M. Hart, Brian J. Smith, Clayton G. Pollock, Zandy Hillis-Starr, Madan K. Oli Oct 2019

Juvenile Hawksbill Residency And Habitat Use Within A Caribbean Marine Protected Area, Thomas H. Selby, Kristen M. Hart, Brian J. Smith, Clayton G. Pollock, Zandy Hillis-Starr, Madan K. Oli

United States National Park Service: Publications

Understanding the spatial ecology of highly mobile marine vertebrates is necessary for informing conservation and management strategies aimed at protecting such species. Buck Island Reef National Monument (BIRNM), off the coast of St. Croix, US Virgin Islands, harbors critical foraging habitat for Critically Endangered juvenile hawksbills Eretmochelys imbricata that exhibit high site fidelity until sexual maturation. Using an array of fixed passive acoustic receivers that covered over 20.2 km2 at its largest configuration and in-water biannual sampling, we analyzed residency patterns and habitat use of 29 hawksbills. High recapture rates allowed for long- term data collection for some individuals, with …


Assessing The Implications Of A Tidal Barrage Power Plant In Hvalfjörður, Iceland, Olive M. Colangelo Oct 2019

Assessing The Implications Of A Tidal Barrage Power Plant In Hvalfjörður, Iceland, Olive M. Colangelo

Independent Study Project (ISP) Collection

As climate change continues to threaten the future state of our world, we are searching for measures to take for mitigation. Among these measures, the most talked about method is the development of renewable energies. Great amounts of attention is paid to solar and wind power, but relatively little effort is given to researching the possibilities of ocean energy, particularly tidal barrage energy. This study assesses the possibility of a tidal barrage plant in Hvalfjörður, Iceland. This hypothetical power plant in Hvalfjörður would have an installed capacity of 840MWh and could produce 613GWh per year. This is less than 0.01% …


Nonlinear Reaction–Diffusion Process Models Improve Inference For Population Dynamics, Xinyi Lu, Perry J. Williams, Mevin B. Hooten, James A. Powell, Jamie N. Womble, Michael R. Bower Sep 2019

Nonlinear Reaction–Diffusion Process Models Improve Inference For Population Dynamics, Xinyi Lu, Perry J. Williams, Mevin B. Hooten, James A. Powell, Jamie N. Womble, Michael R. Bower

United States National Park Service: Publications

Partial differential equations (PDEs) are a useful tool for modeling spatiotemporal dynamics of ecological processes. However, as an ecological process evolves, we need statistical models that can adapt to changing dynamics as new data are collected. We developed a model that combines an ecological diffusion equation and logistic growth to characterize colonization processes of a population that establishes long-term equilibrium over a heterogeneous environment. We also developed a homogenization strategy to statistically upscale the PDE for faster computation and adopted a hierarchical framework to accommodate multiple data sources collected at different spatial scales. We highlighted the advantages of using a …


Permafrost Hydrology Drives The Assimilation Of Old Carbon By Stream Food Webs In The Arctic, Jonathan A. O’Donnell, Michael P. Carey, Joshua C. Koch, Xiaomei Xu, Brett A. Poulin, Jennifer Walker, Christian E. Zimmerman Sep 2019

Permafrost Hydrology Drives The Assimilation Of Old Carbon By Stream Food Webs In The Arctic, Jonathan A. O’Donnell, Michael P. Carey, Joshua C. Koch, Xiaomei Xu, Brett A. Poulin, Jennifer Walker, Christian E. Zimmerman

United States National Park Service: Publications

Permafrost thaw in the Arctic is mobilizing old carbon (C) from soils to aquatic ecosystems and the atmosphere. Little is known, however, about the assimilation of old C by aquatic food webs in Arctic watersheds. Here, we used C isotopes (d13C, D14C) to quantify C assimilation by biota across 12 streams in arctic Alaska. Streams spanned watersheds with varying permafrost hydrology, from ice-poor bedrock to ice-rich loess (that is, yedoma). We measured isotopic content of (1) C sources including dissolved organic C (DOC), dissolved inorganic C (DIC), and soil C, and (2) stream biota, including benthic biofilm and macroinvertebrates, and …


Social Interactions Do Not Drive Territory Aggregation In A Grassland Songbird, S.K. Winnicki, S.M. Munguia, E.J. Williams, W.A. Boyle Aug 2019

Social Interactions Do Not Drive Territory Aggregation In A Grassland Songbird, S.K. Winnicki, S.M. Munguia, E.J. Williams, W.A. Boyle

United States National Park Service: Publications

Understanding the drivers of animal distributions is a fundamental goal of ecology and informs habitat management. The costs and benefits of colonial aggregations in animals are well established, but the factors leading to aggregation in territorial animals remain unclear. Territorial animals might aggregate to facilitate social behavior such as (1) group defense from predators and/or parasites, (2) cooperative care of offspring, (3) extra-pair mating, and/or (4) mitigating costs of extra-pair mating through kin selection. Using experimental and observational methods, we tested predictions of all four hypotheses in a tallgrass prairie in northeast Kansas, United States. Grasshopper Sparrow (Ammodramus savannarum) males …


Vegetation Monitoring At Homestead National Monument Of America, Nebraska, 1998–2017, Sherry A. Leis Aug 2019

Vegetation Monitoring At Homestead National Monument Of America, Nebraska, 1998–2017, Sherry A. Leis

United States National Park Service: Publications

Executive Summary

The Heartland Inventory and Monitoring Network has sampled permanent monitoring sites in three vegetation community types (restored prairie, successional forest, and bur oak forest) at Homestead National Monument of America since 1998 (includes nine sample years). Network scientists record each species, aerial cover estimates of ground flora, diameter at breast height of midstory and overstory trees, and tree regeneration frequency (tree seedlings and saplings) within these permanent sites.

The park has experienced similar periods of drought and wetness through the monitoring record. Ground cover estimates indicate that prairie litter and bare ground are negatively related; prescribed fire cycles …


Evaluating Oyster Aquaculture’S Cost-Effectiveness As A Nitrogen Removal Best Management Practice – A Case Study Of The Delaware Inland Bays, Jefferson F. Flood Jun 2019

Evaluating Oyster Aquaculture’S Cost-Effectiveness As A Nitrogen Removal Best Management Practice – A Case Study Of The Delaware Inland Bays, Jefferson F. Flood

Journal of Ocean and Coastal Economics

Disease and overfishing have led to a dramatic decline in wild populations and subsequent harvests of the eastern oyster Crassostrea virginica over the past few decades in Delaware and other states along the Atlantic Coast. However, in addition to their value as food to consumers, oysters, whether wild populations or cultured stocks, can provide ecosystem services such as nutrient removal, which may result in localized water quality improvements. Consequently, recent policies in Delaware have sought to establish and grow an oyster aquaculture industry. However, a key challenge to achieving efficient levels of industry growth and water quality improvements is that …


Bird Monitoring At Homestead National Monument Of America, Nebraska, Status Report 2009–2017, David G. Peitz, Lloyd W. Morrison, Kristen L. Mecke Jun 2019

Bird Monitoring At Homestead National Monument Of America, Nebraska, Status Report 2009–2017, David G. Peitz, Lloyd W. Morrison, Kristen L. Mecke

United States National Park Service: Publications

Executive Summary

In 2009, the Heartland Inventory Monitoring Network initiated breeding bird surveys on Homestead National Monument of America, Nebraska, to address two objectives: (1) to monitor changes in bird community composition and abundance, and (2) to improve our understanding of relationships between breeding birds and habitat, and the effects of management actions on those relationships. This report evaluates trends in the park’s breeding bird populations in the context of trends observed within the North American Bird Conservation Initiative’s (NABCI) Central Mixed Grass Prairie Bird Conservation Region, the region in which the park is located. By doing so, we can …