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Waldo Lake Research In 2003, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Rich Miller, Laura Johnson, Robert Leslie Annear May 2004

Waldo Lake Research In 2003, Mark D. Sytsma, John Rueter, Richard Petersen, Roy Koch, Scott A. Wells, Rich Miller, Laura Johnson, Robert Leslie Annear

Civil and Environmental Engineering Faculty Publications and Presentations

This report summarizes the first year of an effort to develop a more complete understanding of the physical, chemical, and biological characteristics that drive the ecological processes of Waldo Lake. Modern limnology recognizes the importance of watershed processes as well as in- lake processes in lake ecosystem functioning. Therefore, the approach included consideration of watershed hydrology and forcing functions that determine hydrodynamics of the system as well physical and chemical factors that may be important in regulating primary production in the lake. Data collected since 1998 was summarized and bathymetry of the basin was mapped using state-of-the-art digital depth sounding …


Habitat Preferences Of Four Species Of Lizards Found At The Las Vegas Springs Preserve, Scott Garncarz May 2004

Habitat Preferences Of Four Species Of Lizards Found At The Las Vegas Springs Preserve, Scott Garncarz

UNLV Theses, Dissertations, Professional Papers, and Capstones

Developing an understanding of the habitat usage of reptiles is important when trying to develop a management or restoration plan that is compatible with what is known of the reptile species that are being investigated. There are many lizard species found in the Mojave Desert, but there are only four known to inhabit the Las Vegas Springs Preserve (LVSP) in Las Vegas, Nevada. In the LVSP, sites are going to be restored with native Mojave Desert vegetation. Since there are many habitat types in the Mojave Desert, we must determine which types would be best suited for the four species …


Quantifying Losses Of Understory Forage In Aspen Stands On The Dixie And Fishlake National Forests, Barton R. Stam May 2004

Quantifying Losses Of Understory Forage In Aspen Stands On The Dixie And Fishlake National Forests, Barton R. Stam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The West has lost up to 60% of its historic aspen stands over the last century, probably as a result of the successional tendency of aspen to be replaced by coniferous species in the absence of periodic fires. One of several major impacts of this change is the loss of understory forage as conifer canopy cover increases. I measured understory biomass in aspen stands ranging from 0% to 81 % absolute conifer cover in the canopy and found that understory production declines exponentially as conifers replace aspen. I also did an economic analysis to determine the value of the forage …


Response Of A Peatland Ecosystem To Stratospheric Ozone Reduction In Tierra Del Fuego, Thomas Matthew Robson May 2004

Response Of A Peatland Ecosystem To Stratospheric Ozone Reduction In Tierra Del Fuego, Thomas Matthew Robson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tierra del Fuego, at the southernmost tip of South America, is influenced by ozone depletion. The landscape of southern and western Tierra de! Fuego is dominated by peatlands; they are important locally and in the context of global climate change, because they store large quantities of organic carbon.

To determine the influence of solar ultraviolet-B radiation (UV-B) on a Tierra de! Fuego peatland, we selectively filtered solar UV-Bin ten pairs of plots. Polyfluorine filters were used to create the Near-Ambient-UV-B Treatment (90% solar UV-B), and polyester filters to create the Reduced-UV-B Treatment ( 17% solar UV-B). These filters were first …


Watershed Management To Control Pollution In The Ayuquila River, Jalisco, Mexico, Luis Manuel Martinez Rivera May 2004

Watershed Management To Control Pollution In The Ayuquila River, Jalisco, Mexico, Luis Manuel Martinez Rivera

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ayuquila River watershed is important to western Mexico because of its biodiversity, physiography, fisheries resources, and water production. However, human activities are continuingly affecting natural resources within the basin. Soil erosion, as result of land use change, agriculture in steep land, extensive grazing activities and forest fires; and water diversion and pollution of the Ayuquila River are two relevant issues that have affected the natural resources of this watershed.

This river system plays an important role in wildlife conservation, containing 29 fish species, of which 12 are found inside the BRSM. The River also contains nine species of crustacean, …


Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix, Spencer M. Steinberg Apr 2004

Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix, Spencer M. Steinberg

Separations Campaign (TRP)

The recovery of iodine released during the processing of used nuclear fuel poses a significant challenge to the transmutation of radioactive iodine. During the first two years of this program the use of Fullerene Containing Carbon (FCC) compounds and Natural Organic Matter (NOM) as potential sorbents for iodine release from the reprocessing of nuclear fuel was examined. This work also included the development of bench-scale testing capabilities at UNLV to allow the testing of the FCC and NOM materials in a simulated process off-gas environment. In the final year of the project we will complete studies of FCC and NOM …


Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy Apr 2004

Use Of Positron Annihilation Spectroscopy For Stress-Strain Measurements, Ajit K. Roy

Transmutation Sciences Materials (TRP)

The purpose of this collaborative research project involving the University of Nevada Las Vegas (UNLV) and Idaho State University (ISU) is to evaluate the feasibility of determining residual stresses of welded, bent (three-point-bend), and cold-worked engineering materials using a new nondestructive technique based on positron annihilation spectroscopy (PAS). The proposed technique is to use γ-rays from a small MeV electron linear accelerator (Linac) to generate positrons inside the test sample via 2 pair production. This method can be used for materials characterization and investigation of defects in thick samples that usually cannot be accomplished by conventional positron technique or other …


Water Current, Volume 36, No. 2. Spring 2004 Apr 2004

Water Current, Volume 36, No. 2. Spring 2004

Water Current Newsletter

Contents

• June Tour Focuses on Competing Uses for Platte River Water and Basin Development by Steve Ress

• First Water Law, Policy and Science Conference Sets the Bar High by Steve Ress

• From the Director

• Meet the Faculty

• Helping Small Towns Reduce Arsenic in Drinking Water by Steve Ress

• GIS mapping tool helps officials track livestock diseases by Steve Ress

• News from the Water Sciences Laboratory

• Involve Public in Hard Decisions Regarding Science and Policy, Agency head Says by George Green

• Pederson and Graduate Student Stay Busy Chasing Waterfalls

Water News Briefs


Floodplain Habitat Restoration At Thunder Ranch, Utah, U.S. Department Of The Interior, Bureau Of Reclamation Apr 2004

Floodplain Habitat Restoration At Thunder Ranch, Utah, U.S. Department Of The Interior, Bureau Of Reclamation

All U.S. Government Documents (Utah Regional Depository)

The Upper Colorado River Endangered Fish Recovery Program (Recovery Program) is proposing to restore endangered fish habitat at 330 acres of Green River bottomlands located on the Thunder Ranch near Jensen, Utah. The Recovery Program acquired a total of 455 acres of easement from Thunder Ranch to protect and improve floodplain habitat for the benefit of endangered Colorado River fishes. The project area is located adjacent to the Green River within an old meander river channel. Several ponds and wetlands exist in the project area, but are isolated from the Green River by an earth-filled levee. By notching the existing …


Using The Trees To Understand The Forest: Evaluating The Risks Of The Panama Canal Amplification Project, Caroline Gross Apr 2004

Using The Trees To Understand The Forest: Evaluating The Risks Of The Panama Canal Amplification Project, Caroline Gross

Independent Study Project (ISP) Collection

For over a decade, the Panama Canal Authority (ACP) and its United States predecessor have contemplated a Canal Amplification Project to allow larger boats to pass through the Panama Canal. This project, as it is currently understood, would involve the construction of a new, “third” set of locks with greater capacity, the widening of channels within the Canal, and the flooding of approximately 45,000 hectares of land currently occupied by campesinos/as. Since the passage of a 1999 law that expanded the definition of the Panama Canal Watershed by 63 percent, some campesinos/as have united to oppose the flooding of their …


Draft Aquaculure Plan For Exmouth Gulf, Department Of Fisheries Apr 2004

Draft Aquaculure Plan For Exmouth Gulf, Department Of Fisheries

Fisheries Management Papers

The Plan’s objective is to provide a sound strategy for developing future aquaculture activities in Exmouth Gulf, while at the same time conserving the unique environment of Exmouth Gulf for present and future generations, and minimising conflict with existing and future users of Exmouth Gulf.


Draft Aquaculture Plan For Shark Bay., Department Of Fisheries Apr 2004

Draft Aquaculture Plan For Shark Bay., Department Of Fisheries

Fisheries Management Papers

The Department of Fisheries has prepared this draft aquaculture plan for Shark Bay to provide an agreed framework for future management of aquaculture. The final plan will assist prospective aquaculturists in preparing proposals and will guide the Department of Fisheries in the decision making process for aquaculture licence and lease applications. The plan identifies constraints to aquaculture development and areas where aquaculture may occur. It also identifies species that may be used for aquaculture development. Implementation of this plan will ensure that aquaculture can occur in a sustainable manner, while retaining the unique features of Shark Bay.


A Spatial Analysis Of The Impact Of Development On Wetland Habitat In Mount Pleasant, South Carolina, Jenna Medlin Apr 2004

A Spatial Analysis Of The Impact Of Development On Wetland Habitat In Mount Pleasant, South Carolina, Jenna Medlin

Masters Theses & Specialist Projects

In response to growing concerns over wetland habitat loss and the associated impact on water resources, federal and state legislation has been enacted to protect vulnerable wetland habitats from the impacts of humans. In order to examine the efficacy of current coastal resource policy and its implementation, a study was conducted in Mount Pleasant, South Carolina, a coastal city of the Atlantic, focusing on the quantification of wetland habitat change over time within a specific area of interest. The study incorporated an assessment of the effects of escalating population pressures and subsequent urban development on local wetland habitats due to …


Fisheries Occasional Publication No. 6 - Anglers Guide To Assessing Reproductive Stage In Fish, Kim Smith, Mike Mackie, Department Of Fisheries Western Australia Apr 2004

Fisheries Occasional Publication No. 6 - Anglers Guide To Assessing Reproductive Stage In Fish, Kim Smith, Mike Mackie, Department Of Fisheries Western Australia

Fisheries Occasional Publications

What is a gonad?

"Gonad" is a general term for a reproductive organ, and is used to describe both ovaries and testes. In male and female fish, the gonad is an elongated organ lying along the upper wall of the gut cavity (i.e. running immediately under the vertebral column). The gonad gonad has 2 lobes. Both lobes are attached to the body near the anus and extend forward inside the gut cavity.

As fish gonads ripen, they become larger, heavier and change colour. Immature and undeveloped adult gonads are very small, strap-like in shape, pinkish in colour and translucent (i.e. …


Scwds Briefs: Volume 20, Number 1 (April 2004) Apr 2004

Scwds Briefs: Volume 20, Number 1 (April 2004)

Southeastern Cooperative Wildlife Disease Study: Publications


• First Culture of the STARI Agent for Lyme disease, caused by Borrelia burgdorferi sensulato, the most common tick-borne disease of humans worldwide and the most frequently reported vector-borne disease in the United States.
• Unusual wild elk mortality that began in late January to early February 2004 in the Red Rim area southwest of Rawlings, Wyoming, has been preliminarily diagnosed as lichen (Xanthoparmelia chlorochroa) toxicosis.
• During 2003, hemorrhagic disease (HD) was documented in seven states through virus isolation at SCWDS. Most of our isolations were associated with an outbreak in western Idaho and adjoining eastern Washington. Both epizootic …


Factors Influencing Seagrass Recovery In Feather Sound, Tampa Bay, Florida, Feather Sound Seagrass Recovery Workgroup Apr 2004

Factors Influencing Seagrass Recovery In Feather Sound, Tampa Bay, Florida, Feather Sound Seagrass Recovery Workgroup

Reports

This document is a summary of the findings and recommendations of the Feather Sound Seagrass Recovery Workgroup.

In response to nutrient load reductions and resulting clearer water, seagrasses have expanded significantly in many areas of Tampa Bay since the mid-1980s. However, the recovery rate and expansion of seagrasses in several areas, especially in the Feather Sound region of Old Tampa Bay, have been much slower. This project was designed to examine factors that may be affecting seagrass recovery and growth in the Feather Sound region compared to three other areas of Old Tampa Bay.


The Effects Of Off-Road Vehicle Use In Desert Tortoise (Gopherus Agassizii) Habitats, Brent D. Clark Apr 2004

The Effects Of Off-Road Vehicle Use In Desert Tortoise (Gopherus Agassizii) Habitats, Brent D. Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

The desert tortoise (Gopherus agassizii) populations have been in decline and have been placed on the endangered species list. No single factor is ultimately responsible for the tortoise decline. It is a combination of events that collectively have a negative impact. I chose to focus my study on only one factor, off-road vehicles. By evaluating the damage done to the terrain by off-road vehicles, a better understanding of their impact on the tortoise populations can be assessed and protective measures taken.

The amount of available vegetation does not seem to play a role in their decisions of which plants to …


Defining Soil Type And Habitat Characteristics Of The Arctomecon Californica, Philip S. Childers Apr 2004

Defining Soil Type And Habitat Characteristics Of The Arctomecon Californica, Philip S. Childers

UNLV Theses, Dissertations, Professional Papers, and Capstones

A. californica can be considered a rare endemic species, which is believed to be restricted by unique soil relationships. These relationships make the species vulnerable to anthropogenic habitat disturbance. Although A. californica is listed as critically endangered by the state of Nevada, further research is needed before the species can be listed as federally endangered or threatened. This study used primary observational data and secondary GIS compatible data to characterize A. californica habitat. Representative sampling techniques were used to select observations from derived soil types. Although a majority of A. californica populations were found to occur in gypsic soil types, …


Adult Male Emigration And A Female-Based Social Organization In Swift Foxes, Vulpes Velox, Jan F. Kamler, Warren B. Ballard, Eric M. Gese, Robert L. Harrison, Seija Karki, Kevin Mote Apr 2004

Adult Male Emigration And A Female-Based Social Organization In Swift Foxes, Vulpes Velox, Jan F. Kamler, Warren B. Ballard, Eric M. Gese, Robert L. Harrison, Seija Karki, Kevin Mote

United States Department of Agriculture Wildlife Services: Staff Publications

Members of the family Canidae are distinguished from other carnivore families by pair bonding and male care of the young. Because of the importance of food provisioning and territorial defiance by males, social structure among canids is shared or even dominated by males. However, small, insectivorous species of canids show little male parental care, although whether social structure differs from other canids is unknown. We combined data from three independent research projects on a small canid, the swift fox, to help elucidate the social organization of this species. Based on data on movements of 35 adult mated pairs and the …


Embryonic Responses To Variation In Oviductal Oxygen In The Lizard Sceloporus Undulatus From New Jersey And South Carolina, Usa, Scott L. Parker, Robin M. Andrews, Tom Mathies Apr 2004

Embryonic Responses To Variation In Oviductal Oxygen In The Lizard Sceloporus Undulatus From New Jersey And South Carolina, Usa, Scott L. Parker, Robin M. Andrews, Tom Mathies

United States Department of Agriculture Wildlife Services: Staff Publications

Viviparity in reptiles is hypothesized to evolve in cold climates at high latitudes and high elevations through selection for progressively longer periods of egg retention. Oxygen consumption of embryos increases during development and therefore longer periods of egg retention should be associated with maternal or embryonic features that enhance embryonic oxygen availability. We tested the hypotheses that embryos of the oviparous lizard Sceloporus undulatus from a high-latitude population in New Jersey are oviposited at more advanced developmental stages and have a higher growth rate at low oxygen partial pressures (pO2) than embryos from a low-latitude population …


Management Of Vegetation To Reduce Wildlife Hazards At Airports, Brian E. Washburn, Thomas W. Seamans Apr 2004

Management Of Vegetation To Reduce Wildlife Hazards At Airports, Brian E. Washburn, Thomas W. Seamans

United States Department of Agriculture Wildlife Services: Staff Publications


Wildlife-aircraft collisions (wildlife strikes) pose a serious safety risk to aircraft. Wildlife strikes cost civil and military aviation at least S490 million annually in the United States (Cleary et al. [I]). Over 46,500 wildlife strikes with civil aircraft were reported to the U.S. Federal Aviation Administration (FAA) during 1990-2002 (Cleary et al. 111). Aircraft collisions with birds accounted for 97% of the reported strikes, whereas strikes with mammals and reptiles were 3% and Larus spp.), waterfowl such as Canada geese (Branta canadensis), raptors (hawks and owls), and blackbirds (Ictennae)/starlings (Sturnus vulgaris) are the species presently of …


A Comparison Of Anuran Species Richness Between Primary And Secondary Forest In São Francisco Do Pará, Michael Reichert Apr 2004

A Comparison Of Anuran Species Richness Between Primary And Secondary Forest In São Francisco Do Pará, Michael Reichert

Independent Study Project (ISP) Collection

Deforestation in the Amazon has become a serious conservation issue. The process of destruction of primary forest results in the creation of secondary forest that differs from primary forest in a number of important ways. Anurans (frogs and toads) are one group that may be affected by the loss of primary forest and creation of secondary forest areas, and are an important focus for conservation efforts. Previous studies on anuran reactions to loss of primary forest have been few and inconclusive. This study examined anuran species richness in an area of primary and secondary forest in order to determine whether …


Coyote Depredation Management: Current Methods And Research Needs, Brian R. Mitchell, Michael M. Jaeger, Reginald H. Barrett Mar 2004

Coyote Depredation Management: Current Methods And Research Needs, Brian R. Mitchell, Michael M. Jaeger, Reginald H. Barrett

United States Department of Agriculture Wildlife Services: Staff Publications

This paper examines the severity of livestock depredation by coyotes (Canis latrans), reviews evidence implicating breeding (or “alpha”) coyotes in the majority of incidents, evaluates currently used depredation control techniques, and suggests directions for future research. Nonlethal control ranges from varied animal husbandry practices to coyote behavioral modification or sterilization. These methods show significant promise but have not been proven effective in controlled experiments. Therefore, many livestock producers rely on lethal control, and most employ nonselective strategies aimed at local population reduction. Sometimes this approach is effective; other times it is not. This strategy can fail because the …


Efficacy Of Aircraft Landing Lights In Stimulating Avoidance Behavior In Birds, Bradley F. Blackwell, Glen E. Burnhardt Mar 2004

Efficacy Of Aircraft Landing Lights In Stimulating Avoidance Behavior In Birds, Bradley F. Blackwell, Glen E. Burnhardt

United States Department of Agriculture Wildlife Services: Staff Publications

Aircraft collisions with wildlife (primarily birds) are costly in terms of injury or loss of human life, loss of the animals involved, damage to property and business, and the use of lethal control of wildlife at airports worldwide. One potential nonlethal technique to reduce bird–aircraft collisions—pulsed white and wavelength-specific aircraft-mounted light—has been considered for nearly 3 decades, but the efficacy of the technique has not been evaluated quantitatively. We tested the hypothesis that during daylight, captive birds exposed to an approaching ground-based vehicle exhibiting pulsing 250-W white aircraft landing lights would initiate avoidance behavior more quickly than birds experiencing an …


Proximate Cues For Ovarian Recrudescence And Ovulation In The Brown Treesnake (Boiga Irregularis) Under Laboratory Conditions, Tom Mathies, Elizabeth A. Franklin, Lowell A. Miller Mar 2004

Proximate Cues For Ovarian Recrudescence And Ovulation In The Brown Treesnake (Boiga Irregularis) Under Laboratory Conditions, Tom Mathies, Elizabeth A. Franklin, Lowell A. Miller

United States Department of Agriculture Wildlife Services: Staff Publications

The reproductive biology of the brown treesnake (Boiga irregularis), an invasive tropical species known primarily for the extensive ecological damage it has caused on the island of Guam (Savidge 1987), is poorly understood. This is not for lack of sampling effort by researchers-it is simply because reproduction apparently occurs in all months of the year (Rodda et al. 1999) and periodic sampling in such systems cannot detect the phenology of major reproductive events (e.g., ovarian recrudescence, ovulation, oviposition) and other important life history attributes (e.g., frequency of reproduction). In such systems, repeated observations of individuals may be the …


Rocky Mountain Wolf Recovery 2004 Annual Report Mar 2004

Rocky Mountain Wolf Recovery 2004 Annual Report

Rocky Mountain Wolf Recovery: Annual Reports

The gray wolf (Canis lupus) population in the Northern Rocky Mountain (NRM) states (Idaho, Montana, and Wyoming) continued to increase in distribution and numbers (Figure 1, Tables 4a, 4b). Estimates of wolf numbers at the end of 2004 were 452 wolves in the Central Idaho Recovery Area (CID), 324 in the Greater Yellowstone Recovery Area (GYA), and 59 in the Northwest Montana Recovery Area (NWMT) for a total of 835 wolves (Figure 1, Table 4a). By state boundaries, there were an estimated 422 wolves in the state of Idaho, 260 in Wyoming and 153 in Montana (Table 4b). …


Draft Plan Of Management For The Kalbarri Blue Holes Fish Habitat Protection Area., Department Of Fisheries Mar 2004

Draft Plan Of Management For The Kalbarri Blue Holes Fish Habitat Protection Area., Department Of Fisheries

Fisheries Management Papers

The overall objective of the proposed FHPA and the associated Plan of Management is to conserve and protect a portion of the near-shore reef ecosystem in the vicinity of the Blue Holes, and to manage activities within the area, to promote the observation and protection of fish living within the area. Strong community commitment has already been demonstrated, and this is crucial in the implementation of the proposed management plan


Fish Stock And Fishery Enhancement In Western Australia. A Summary Report., Department Of Fisheries Mar 2004

Fish Stock And Fishery Enhancement In Western Australia. A Summary Report., Department Of Fisheries

Fisheries Management Papers

This summary paper provides an overview of the key proposals set out in the full policy discussion paper, Fisheries Management Paper No 175. It does not discuss the theoretical background for the framework presented and therefore readers interested in such discussion are directed to Fisheries Management Paper No 175.

Both papers have been prepared to encourage public involvement in the development of policy for stock enhancement within Western Australian waters. Stock enhancement can involve an existing fishery or creation of a new fishery through the translocation of fish. It affects both public and private waters.


Coyote Attacks: An Increasing Suburban Problem, Robert M. Timm, Rex O. Baker, Joe R. Bennett, Craig C. Coolahan Mar 2004

Coyote Attacks: An Increasing Suburban Problem, Robert M. Timm, Rex O. Baker, Joe R. Bennett, Craig C. Coolahan

Vertebrate Pest Conference Proceedings: 21st (2004)

Coyote attacks on humans and pets have increased within the past 5 years in California. We discuss documented occurrences of coyote aggression and attacks on people, using data from USDA Wildlife Services, the California Department of Fish & Game, and other sources. Forty-eight such attacks on children and adults were verified from 1998 through 2003, compared to 41 attacks during the period 1988 through 1997; most incidents occurred in Southern California near the suburban-wildland interface. Attack incidents are typically preceded by a sequence of increasingly bold coyote behaviors, including: nighttime coyote attacks on pets; sightings of coyotes in neighborhoods at …


Refuge Update – March/April 2004, Volume 1, Number 2 Mar 2004

Refuge Update – March/April 2004, Volume 1, Number 2

RefugeUpdate (USFWS-NWRS)

Table of Contents:
An Encyclopedia for the Refuge, page 4
Awarded for Excellence, page 5
MBNA Donates for Refuge System Projects, page 16
The Thoughts of a Detailee, page 19