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Full-Text Articles in Physical Sciences and Mathematics

Nonlinear Dynamics In Ecosystem Response To Climatic Change: Case Studies And Policy Implications, Virginia R. Burkett, Douglas A. Wilcox, Wilcox Stottlemyer, Wylie Barrow, Dan Fagre, Jill Baron, Jeff Price, Jennifer L. Nielsen, Craig D. Allen, David L. Peterson, Greg Ruggerone, Thomas Doyle Sep 2005

Nonlinear Dynamics In Ecosystem Response To Climatic Change: Case Studies And Policy Implications, Virginia R. Burkett, Douglas A. Wilcox, Wilcox Stottlemyer, Wylie Barrow, Dan Fagre, Jill Baron, Jeff Price, Jennifer L. Nielsen, Craig D. Allen, David L. Peterson, Greg Ruggerone, Thomas Doyle

United States Geological Survey: Staff Publications

Many biological, hydrological, and geological processes are interactively linked in ecosystems. These ecological phenomena normally vary within bounded ranges, but rapid, nonlinear changes to markedly different conditions can be triggered by even small differences if threshold values are exceeded. Intrinsic and extrinsic ecological thresholds can lead to effects that cascade among systems, precluding accurate modeling and prediction of system response to climate change. Ten case studies from North America illustrate how changes in climate can lead to rapid, threshold-type responses within ecological communities; the case studies also highlight the role of human activities that alter the rate or direction of …


Factors Affecting Songbird Nest Survival And Brood Parasitism In The Rainwater Basin Region Of Nebraska, Max Post Van Der Burg Aug 2005

Factors Affecting Songbird Nest Survival And Brood Parasitism In The Rainwater Basin Region Of Nebraska, Max Post Van Der Burg

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Water Quality Trading: What Can We Learn From 10 Years Of Wetland Mitigation Banking?, Eric Raffini, Morgan Robertson Jul 2005

Water Quality Trading: What Can We Learn From 10 Years Of Wetland Mitigation Banking?, Eric Raffini, Morgan Robertson

United States Environmental Protection Agency: Staff Publications

In 2003 the U.S. Environmental Protection Agency issued its Water Quality Trading Policy. Water quality trading allows facilities facing high pollution-control costs to meet their regulatory requirements by purchasing environmentally equivalent or superior pollution reductions from another source, often at a lower cost. The policy, which hopes to achieve "water quality and environmental benefits greater than would otherwise be achieved under more traditional regulatory approaches," established the ground rules for trading and encourages states, interstate agencies, and tribes to develop and implement water quality trading programs for nutrients, sediments, and other pollutants. The policy generated controversy among some stakeholder groups; …


The July 2003 Dakota Hailswaths: Creation, Characteristics, And Possible Impacts, Matthew D. Parker, Ian Ratcliffe, Geoffrey M. Henebry Jul 2005

The July 2003 Dakota Hailswaths: Creation, Characteristics, And Possible Impacts, Matthew D. Parker, Ian Ratcliffe, Geoffrey M. Henebry

School of Natural Resources: Faculty Publications

The authors investigate the meteorology associated with two elongated swaths of crop damage produced by severe hailstorms that crossed North Dakota and South Dakota on 4 July and 20 July 2003. These hailswaths, which were observed in a Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) image time series, each persisted for more than a month and were associated with local temperature increases, presumably owing to the enhanced Bowen ratio over dry, crop-free ground. This paper documents the creation and evolution of the convective storms that produced the hailswaths, and then presents evidence that devegetated hailswaths may impact …


Seasonal And Interannual Varialbility In Evapotranspiration Of Native Tallgrass Prairie And Cultivated Wheat Ecosystems, By G.G. Burba, S.B. Verma, George G. Burba, Shashi B. Verma Jul 2005

Seasonal And Interannual Varialbility In Evapotranspiration Of Native Tallgrass Prairie And Cultivated Wheat Ecosystems, By G.G. Burba, S.B. Verma, George G. Burba, Shashi B. Verma

School of Natural Resources: Faculty Publications

No abstract provided.


Patterns Of Fish Use And Piscivore Abundance Within A Reconnected Saltmarsh Impoundment In The Northern Indian River Lagoon, Florida, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak Apr 2005

Patterns Of Fish Use And Piscivore Abundance Within A Reconnected Saltmarsh Impoundment In The Northern Indian River Lagoon, Florida, Philip W. Stevens, Clay L. Montague, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Nearly all saltmarshes in east-central, Florida were impounded for mosquito control during the 1960s. The majority of these marshes have since been reconnected to the estuary by culverts, providing an opportunity to effectively measure exchange of aquatic organisms. A multi-gear approach was used monthly to simultaneously estimate fish standing stock (cast net), fish exchange with the estuary (culvert traps), and piscivore abundance (gill nets and bird counts) to document patterns of fish use in a reconnected saltmarsh impoundment. Changes in saltmarsh fish abundance, and exchange of fish with the estuary reflected the seasonal pattern of marsh flooding in the northern …


Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree Apr 2005

Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree

United States Geological Survey: Staff Publications

In Nebraska, a large number (>200) of shallow sand-point and cased wells completed in coarse alluvial sediments along rivers and lakes still are used to obtain drinking water for human consumption, even though construction of sand-point wells for consumptive uses has been banned since 1987. The quality of water from shallow domestic wells potentially vulnerable to seepage from septic systems was evaluated by analyzing for the presence of tracers and multiple isotopes. Samples were collected from 26 sand-point and perforated, cased domestic wells and were analyzed for bacteria, coliphages, nitrogen species, nitrogen and boron isotopes, dissolved organic carbon (DOC), …


The Communicator, Volume [1], Issue [1], April 2005 Apr 2005

The Communicator, Volume [1], Issue [1], April 2005

The Communicator: News from the Nebraska Cooperative Fish and Wildlife Research Unit

Getting to Know Us–Valerie Egger Current Research–Craig R. Allen Landowner Incentives Program (LIP) Graduate Students (Donald (Don) Wardwell; Aaron Lotz; Elizabeth (Beth) Forbus) New Location Research (cont'd) Resilience in Ecosystems Cross-Scale Structure in Ecosystems Rainwater Basin Project Career Opportunity Events


The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak Mar 2005

The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The existing scientific literature on offshore benthic assemblages (OBA) residing along the US East and Gulf of Mexico continental shelf was reviewed. Identification was made of any associations between the dominant OBA and particular sediment types and/or bathymetry. Of special interest was the evaluation of reported effects of sand dredge/mining activities on the dominant OBA and recognition of data deficiencies. One hundred and twenty-two references were selected and classified as to type of study with pertinent results extracted. Polychaetes were predominantly cited as the principal infaunal taxa present in studies from both the Gulf of Mexico and US Atlantic coast. …


Influence Of A Hailstreak On Boundary Layer Evolution, Zewdu T. Segele, David J. Stensrub, Ian C. Ratcliffe, Geoffrey M. Henebry Jan 2005

Influence Of A Hailstreak On Boundary Layer Evolution, Zewdu T. Segele, David J. Stensrub, Ian C. Ratcliffe, Geoffrey M. Henebry

School of Natural Resources: Faculty Publications

Severe thunderstorms developed on 20 June 1997 and produced heavy precipitation, damaging winds, and large hail over two swaths in southeastern South Dakota. Calculations of fractional vegetation coverage (scaled from 0 to 1) based upon composite satellite data indicate that, within the hailstreak region, vegetation coverage decreased from 0.50 to near 0.25 owing to the damaging effects of hail on the growing vegetation. The northern edge of the larger hailstreak was located a few kilometers south of Chamberlain, South Dakota, a National Weather Service surface observation site. Hourly observations from Chamberlain and several nearby surface sites in South Dakota are …


Quality Control Of Pre-1948 Cooperative Observer Network Data, Kenneth E. Kunkel, David R. Easterling, Kenneth Hubbard, Kelly Redmond, Karen Andsager, Michael C. Kruk, Michael L. Spinar Jan 2005

Quality Control Of Pre-1948 Cooperative Observer Network Data, Kenneth E. Kunkel, David R. Easterling, Kenneth Hubbard, Kelly Redmond, Karen Andsager, Michael C. Kruk, Michael L. Spinar

School of Natural Resources: Faculty Publications

A recent comprehensive effort to digitize U.S. daily temperature and precipitation data observed prior to 1948 has resulted in a major enhancement in the computer database of the records of the National Weather Service’s cooperative observer network. Previous digitization efforts had been selective, concentrating on state or regional areas. Special quality control procedures were applied to these data to enhance their value for climatological analysis. The procedures involved a two-step process. In the first step, each individual temperature and precipitation data value was evaluated against a set of objective screening criteria to flag outliers. These criteria included extreme limits and …


Effects Of Spring Supplementary Feeding On Population Density And Breeding Success Of Released Pheasants Phasianus Colchicus In Britain, Roger A. H. Draycott, Maureen I. A. Woodburn, John P. Carroll, Rufus B. Sage Jan 2005

Effects Of Spring Supplementary Feeding On Population Density And Breeding Success Of Released Pheasants Phasianus Colchicus In Britain, Roger A. H. Draycott, Maureen I. A. Woodburn, John P. Carroll, Rufus B. Sage

School of Natural Resources: Faculty Publications

The release of hand-reared ring-necked pheasants Phasianus colchicus in summer is a common practice in Britain to increase the number of birds available to hunters in winter. The breeding success of the birds which survive the shooting season is poor. Traditionally, birds are provided with supplementary wheat grain from release until the end of the shooting season (1 February) to maintain body condition and to help hold birds in areas for hunting. During 1997- 2000 we assessed the effect of continuing supplementary feeding into spring on pheasant density and breeding success on seven private shooting estates. On each estate we …


Social Science To Improve Fuels Management: A Synthesis Of Research Relevant To Communicating With Homeowners About Fuels Management, Martha C. Monroe, Lisa Pennisi, Sarah Mccaffrey, Dennis Mileti Jan 2005

Social Science To Improve Fuels Management: A Synthesis Of Research Relevant To Communicating With Homeowners About Fuels Management, Martha C. Monroe, Lisa Pennisi, Sarah Mccaffrey, Dennis Mileti

School of Natural Resources: Faculty Publications

No abstract provided.


Discrete State-Space Approximation Of The Continuous Kalinin-Milyukov-Nash Cascade Of Noninteger Storage Elements, Jozsef Szilagyi Jan 2005

Discrete State-Space Approximation Of The Continuous Kalinin-Milyukov-Nash Cascade Of Noninteger Storage Elements, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.


Flow Routing With Unknown Rating Curves Using A State-Space Reservoir-Cascade-Type Formulation, Jozsef Szilagyi, Gabor Balint, Balazs Gauzer, Peter Bartha Jan 2005

Flow Routing With Unknown Rating Curves Using A State-Space Reservoir-Cascade-Type Formulation, Jozsef Szilagyi, Gabor Balint, Balazs Gauzer, Peter Bartha

School of Natural Resources: Faculty Publications

No abstract provided.


Effects Of Climate And Landcover Change On Stream Discharge In The Ozark Highlands, Usa, Q. Steven Hu, Gary D. Willson, Xi Chen, Adnan Adnan Jan 2005

Effects Of Climate And Landcover Change On Stream Discharge In The Ozark Highlands, Usa, Q. Steven Hu, Gary D. Willson, Xi Chen, Adnan Adnan

School of Natural Resources: Faculty Publications

Stream discharge of a watershed is affected and altered by climate and landcover changes. These effects vary depending on the magnitude and interaction of the changes, and need to be understood so that local water resource availability can be evaluated and socioeconomic development within a watershed be pursued and managed in a way sustainable with the local water resources. In this study, the landcover and climate change effects on stream discharge from the Jacks Fork River basin in the Ozark Highlands of the south-central United States were examined in three phases: site observation and data collection, model calibration and simulation, …


Some Concerns When Using Data From The Cooperative Weather Station Networks: A Nebraska Case Study, Hong Wu, Kenneth G. Hubbard, Jinsheng You Jan 2005

Some Concerns When Using Data From The Cooperative Weather Station Networks: A Nebraska Case Study, Hong Wu, Kenneth G. Hubbard, Jinsheng You

School of Natural Resources: Faculty Publications

In this study, daily temperature and precipitation amounts that are observed by the Cooperative Observer Program (COOP) were compared among geographically close stations. Hourly observations from nearby Automatic Weather Data Network (AWDN) stations were utilized to resolve the discrepancies between the observations during the same period. The statistics of maximum differences in temperature and precipitation between COOP stations were summarized. In addition, the quantitative measures of the deviations between COOP and AWDN stations were expressed by root-mean-square error, mean absolute error, and an index of agreement. The results indicated that significant discrepancies exist among the daily observations between some paired …


Steroid Hormone Levels Are Related To Choice Of Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown, Samrrah A. Raouf, Linda C. Smith, John C. Wingfield Jan 2005

Steroid Hormone Levels Are Related To Choice Of Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown, Samrrah A. Raouf, Linda C. Smith, John C. Wingfield

School of Natural Resources: Faculty Publications

One hypothesis to explain the extensive variation in colony size seen in most
taxa is that individuals sort themselves among groups based on phenotypic characteristics
that correlate with their performance in groups of different sizes. We investigated how
baseline levels of the steroid hormones, corticosterone and testosterone, were associated
with choice of colony size and the likelihood of moving to a different site in later years
in colonially nesting Cliff Swallows (Petrochelidon pyrrhonota) in southwestern Nebraska,
USA, in 2000–2004. We sampled hormone levels of birds caught at colonies and, using
mark–recapture, monitored their movement and choice of colony size …


Is Degradation A Major Problem In Semi-Desert Environments Of The Gobi Region In Southern Mongolia?, Karsten Wesche, Vroni Retzer Jan 2005

Is Degradation A Major Problem In Semi-Desert Environments Of The Gobi Region In Southern Mongolia?, Karsten Wesche, Vroni Retzer

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

This paper tests predictions derived from the non-equilibrium theory of rangeland science. Data were collected in livestock enclosures situated in the relatively moist desert steppes of the Gobi Gurvan Saykhan region of southern Mongolia from 2000 to 2003. Plant community composition and species’ richness in enclosures showed clear differences between years, but these were equally strong in ungrazed controls. Thus, changes were mainly attributed to differences in precipitation between years as opposed to grazing, as no significant effects thereof were detected. This was also confirmed by data on above-ground standing biomass. This changed tremendously over the years, with differences between …


Characterizing Moisture Regimes For Assessing Fuel Availability In North Carolina Vegetation Communities, Roberta A. Bartlette, James Reardon, Gary M. Curcio Jan 2005

Characterizing Moisture Regimes For Assessing Fuel Availability In North Carolina Vegetation Communities, Roberta A. Bartlette, James Reardon, Gary M. Curcio

JFSP Research Project Reports

In the southeastern United States prescription burning, fire danger rating and wildfire suppression strategies are constrained by limited knowledge of the influence of moisture content in live vegetation, organic soils, water table and weather. The interactive influence of these factors on fire behavior is not well studied. The 3+ year long study reported here was conducted to gain direct empirical understanding of seasonal fuel and soil moisture dynamics in shrub-dominated pocosin communities, in coastal Virginia and North Carolina, mixed hardwoods communities containing significant laurel and rhododendron understory fuels in western North Carolina and eastern Tennessee, and longleaf pine communities in …


Fuel Reduction And Restoration Of Pine/Hardwood Ecosystems Severely Impacted By The Recent Southern Pine Beetle (Dendroctonus Frontalis) Epidemic In The Southern Appalachians, James M. Vose, Katherine J. Elliott Jan 2005

Fuel Reduction And Restoration Of Pine/Hardwood Ecosystems Severely Impacted By The Recent Southern Pine Beetle (Dendroctonus Frontalis) Epidemic In The Southern Appalachians, James M. Vose, Katherine J. Elliott

JFSP Research Project Reports

As a result of this most recent SPB epidemic (1999-2003), thousands of hectares of dead pine trees have created wildfire-hazard conditions in the southern Appalachians. One of the challenges for land managers is how to return fire to these ecosystems after (1) nearly a decade of exclusion, and (2) the more recent SPB mortality enhanced fuel loads. Higher fuel loads have the potential to increase fire intensity and severity. At the extremes, fires of high intensity and severity can have a large effect on ecosystem structure and function. The objectives of our research were: (1) to quantify fuel load reduction …


Late-Holocene Flooding And Drought In The Northern Great Plains, Usa, Reconstructed From Tree Rings, Lake Sediments And Ancient Shorelines, M. D. Shapley, W. C. Johnson, D. R. Engstrom, W. R. Osterkamp Jan 2005

Late-Holocene Flooding And Drought In The Northern Great Plains, Usa, Reconstructed From Tree Rings, Lake Sediments And Ancient Shorelines, M. D. Shapley, W. C. Johnson, D. R. Engstrom, W. R. Osterkamp

United States Geological Survey: Staff Publications

During the AD 1990s the Waubay Lakes complex in eastern South Dakota experienced historically unprecedented high water levels. Property damage from this flooding led to an examination of the occurrence of past pluvial episodes and their relation to climate. A lOOO-year hydroclimate reconstruction was developed from local bur oak (Quercus macrocarpa) tree-ring records and lake-sediment cores. Analysis of lake shoreline and drainage features provides late-Quaternary geomorphic context for this high-resolution record. Tree-ring width and shell geochemistry of the ostracode Candona rawsoni show marked coherence, indicating synchronous responses to moisture balance in vegetation and lake salinity; geomorphic evidence …


Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling Jan 2005

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …


The Communicator, Volume [1], Issue [2], September 2005 Jan 2005

The Communicator, Volume [1], Issue [2], September 2005

The Communicator: News from the Nebraska Cooperative Fish and Wildlife Research Unit

People

New Assistant Unit Leader

Current Research

Landowner Incentives Program (LIP)

Amphibians in the Rainwater Basin

Resilience in Ecosystems

Cross-Scale Structure in Ecosystems

Diversity and Ecological Functions: Pollination

Future Research Projects

Impact of White Perch on Walleye

Spatial Risk Assessment of Invasive Species

Impacts on Native Species in Nebraska

Graduate Students (Donald (Don) Wardwell; Elizabeth (Beth) Forbus; Aaron Lotz)

EVENTS

Conferences/Meetings


Population Structure Of Columbia Spotted Frogs (Rana Luteiventris) Is Strongly Affected By The Landscape, W. Chris Funk, Michael S. Blouin, Paul Stephen Corn, Bryce A. Maxell, David S. Pilliod, Stephen Amish, Fred W. Allendorf Jan 2005

Population Structure Of Columbia Spotted Frogs (Rana Luteiventris) Is Strongly Affected By The Landscape, W. Chris Funk, Michael S. Blouin, Paul Stephen Corn, Bryce A. Maxell, David S. Pilliod, Stephen Amish, Fred W. Allendorf

United States Geological Survey: Staff Publications

Landscape features such as mountains, rivers, and ecological gradients may strongly affect patterns of dispersal and gene flow among populations and thereby shape population dynamics and evolutionary trajectories. The landscape may have a particularly strong effect on patterns of dispersal and gene flow in amphibians because amphibians are thought to have poor dispersal abilities. We examined genetic variation at six microsatellite loci in Columbia spotted frogs (Rana luteiventris) from 28 breeding ponds in western Montana and Idaho, USA, in order to investigate the effects of landscape structure on patterns of gene flow. We were particularly interested in addressing …


Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, Dana L. Hahn, Robert J. Dooling Jan 2005

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, Dana L. Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …


Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton Jan 2005

Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton

United States Geological Survey: Staff Publications

Examination of finfish populations for viral and bacterial pathogens is an important component of fish disease control programs worldwide. Two methods are commonly used for collecting tissue samples for bacteriological culture, the currently accepted standards for detection of bacterial fish pathogens. The method specified in the Office International des Epizooties Manual of Diagnostic Tests for Aquatic Animals permits combining renal and splenic tissues from as many as 5 fish into pooled samples. The American Fisheries Society (AFS) Blue Book/US Fish and Wildlife Service (USFWS) Inspection Manual specifies the use of a bacteriological loop for collecting samples from the kidney of …


Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins Jan 2005

Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins

United States Geological Survey: Staff Publications

Taxonomic relationships among red tree voles (Phenacomys longicaudus longicaudus, P. l. silvicola), the Sonoma tree vole (P. pomo), the white-footed vole (P. albipes), and the heather vole (P. intermedius) were examined using 664 base pairs of the mitochondrial cytochrome b gene. Results indicate specific differences among red tree voles, Sonoma tree voles, white-footed voles, and heather voles, but no clear difference between the 2 Oregon subspecies of red tree voles (P. l. longicaudus and P. l. silvicola). Our data further indicated a close relationship between tree voles and albipes, …


High Dispersal In A Frog Species Suggest That It Is Vulnerable To Habitat Fragmentation, W. Chris Funk, Allison E. Greene, Paul Stephen Corn, Fred W. Allendorf Jan 2005

High Dispersal In A Frog Species Suggest That It Is Vulnerable To Habitat Fragmentation, W. Chris Funk, Allison E. Greene, Paul Stephen Corn, Fred W. Allendorf

United States Geological Survey: Staff Publications

Global losses of amphibian populations are a major conservation concern and have generated substantial debate over their causes. Habitat fragmentation is considered one important cause of amphibian decline. However, if fragmentation is to be invoked as a mechanism of amphibian decline, it must first be established that dispersal is prevalent among contiguous amphibian populations using formal movement estimators. In contrast, if dispersal is naturally low in amphibians, fragmentation can be disregarded as a cause of amphibian declines and conservation efforts can be focused elsewhere. We examined dispersal rates in Columbia spotted frogs (Rana luteiventris) using capture– recapture analysis …


An Assessment Of Key Aspects Of Warm And Cool Season Severe Flash Flooding In The Southern Appalachians, W. M. Baldwin, R. Mahmood Jan 2005

An Assessment Of Key Aspects Of Warm And Cool Season Severe Flash Flooding In The Southern Appalachians, W. M. Baldwin, R. Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.