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Kill Rates And Predation Patterns Of Jaguars (Panthera Onca) In The Southern Pantanal, Brazil, Sandra M. C. Cavalcanti, Eric M. Gese 2010 Utah State University, Logan, Department of Wildland Resources,

Kill Rates And Predation Patterns Of Jaguars (Panthera Onca) In The Southern Pantanal, Brazil, Sandra M. C. Cavalcanti, Eric M. Gese

USDA National Wildlife Research Center - Staff Publications

Jaguars (Panthera onca) often prey on livestock, resulting in conflicts with humans. To date, kill rates and predation patterns by jaguars have not been well documented. We studied the foraging ecology of jaguars in an area with both livestock and native prey and documented kill rates, characteristics of prey killed, patterns of predation, and the influence of prey size on the duration at kill sites and the time interval between kills. Between October 2001 and April 2004 we monitored 10 jaguars equipped with global positioning system (GPS) collars. We collected 11,787 GPS locations and identified 1,105 clusters of ...


Feral Swine Behavior Relative To Aerial Gunning In Southern Texas, Tyler A. Campbell, David Long, Bruce Leland 2010 USDA-APHIS-Wildlife Services

Feral Swine Behavior Relative To Aerial Gunning In Southern Texas, Tyler A. Campbell, David Long, Bruce Leland

USDA National Wildlife Research Center - Staff Publications

Feral swine (Sus scrofa) impact resources through their destructive feeding behavior, competition with native wildlife, and impacts to domestic animal agriculture. We studied aerial gunning on feral swine to determine if aerial gunning altered home range and core area sizes, distances between home range centroids, and distances moved by surviving individuals. We collected data before, during, and after aerial gunning in southern Texas. Using Global Positioning System collars deployed on 25 adult feral swine at 2 study sites, we found home range and core area sizes did not differ before and after aerial gunning. However, feral swine moved at a ...


The Effect Of Enclosure Type On The Behavior And Heart Rate Of Captive Coyotes, Stacey P. Brummer, Eric M. Gese, John A. Shivik 2010 USDA-APHIS-Wildlife Services

The Effect Of Enclosure Type On The Behavior And Heart Rate Of Captive Coyotes, Stacey P. Brummer, Eric M. Gese, John A. Shivik

USDA National Wildlife Research Center - Staff Publications

The potential for captivity to elicit changes in animal behavior and physiology is well known. Recent research on captive populations has examined the effect of feeding protocols, enclosure types, and enrichment programs on indices of stress and displays of species-typical behaviors. We investigated the impact of enclosure type upon captive coyotes (Canis latrans) by examining differences in coyote behavior and heart rate, among 3.3m2 kennels (K), 65.5m2 small pens (S), and 1000m2 large pens (L). Time budgets and repertoire of species-specific behaviors were compared among each enclosure type and to a sample of wild (W ...


The Economic Impacts To Commercial Farms From Invasive Monkeys In Puerto Rico, Richard M. Engeman, Jose´ E. Laborde, Bernice U. Constantin, Stephanie A. Shwiff, Parker Hall, Anthony Duffiney, Freddie Luciano 2010 USDA-APHIS-Wildlife Services

The Economic Impacts To Commercial Farms From Invasive Monkeys In Puerto Rico, Richard M. Engeman, Jose´ E. Laborde, Bernice U. Constantin, Stephanie A. Shwiff, Parker Hall, Anthony Duffiney, Freddie Luciano

USDA National Wildlife Research Center - Staff Publications

Beginning in the 1930s and continuing through the 1970s, rhesus macaques and patas monkeys were introduced to presumed secure locations, primarily coastal islets, in Puerto Rico. Escapes into the wild began almost immediately after introduction. Today the combined range of the two species covers approximately 600 km2 of southwestern Puerto Rico, where serious conflicts with agricultural interests have resulted. The Puerto Rico Department of Agriculture surveyed about 90% of commercial farmers in the range of the monkeys to begin quantifying damage by monkeys and the associated economic losses during the years 2002–2006. During that time, total economic losses ...


Management Effects On Breeding And Foraging Numbers And Movements Of Double-Crested Cormorants In The Les Cheneaux Islands, Lake Huron, Michigan, Brian S. Dorr, Tony Aderrnan, Peter H. Butchko, Scott C. Barras 2010 USDA/APHIS/WS National Wildlife Research Center

Management Effects On Breeding And Foraging Numbers And Movements Of Double-Crested Cormorants In The Les Cheneaux Islands, Lake Huron, Michigan, Brian S. Dorr, Tony Aderrnan, Peter H. Butchko, Scott C. Barras

USDA National Wildlife Research Center - Staff Publications

The yellow perch fishery of the Les Cheneaux Islands (LCl) region of Lake Huron, MI suffered a collapse in 2000, attributed in part to the increase of double-crested cormorants (Phalocrocorax auritus) in the region. A management program involving egg-oiling and lethal culling was initiated in 2004 to reduce cormorant foraging on yellow perch in the LC1. Counts of cormorant nests, nests oiled, cormorants culled, and aerial counts and telemetry surveys were used to evaluate management. Management contributed to a 74% reduction of cormorants on breeding colonies from 2004 to 2007. Cormorants used the LC1 area significantly more (P<0.05) than surrounding areas. Aerial counts of foraging cormorants declined significantly (P<0.05) over the entire survey area but not within the LCl proper. However, aerial counts of cormorants in the LCI were five-fold less than cormorant counts in the same area in 1995. Reduced cormorant numbers were attributed in part to the elimination of cormorant nesting on a large colony due to the introduction of raccoons. Although the numbers of cormorants using the LC1 did not decline, flocks were significantly smaller and more dispersed after management began. The reduced number of cormorants from 1995 levels and more dispersed foraging likely reduced predation on fish stocks including yellow perch in the LC1. Our findings indicate that the relationship between reduction in cormorant breeding numbers and reduced cormorant foraging in a given area is complex and may be influenced by density dependent factors such as intraspecific competition and quality of the forage base.


An Evaluation Of Diazacon As A Potential Contraceptive In Non-Native Rose-Ringed Parakeets, Mark Lambert, Giovanna Massel, Christi Yoder, David Cowan 2010 Food and Environment Research Agency, United Kingdom

An Evaluation Of Diazacon As A Potential Contraceptive In Non-Native Rose-Ringed Parakeets, Mark Lambert, Giovanna Massel, Christi Yoder, David Cowan

USDA National Wildlife Research Center - Staff Publications

Rose-ringed parakeets (Psittacula krameri) have become widely established outside their native range through accidental or deliberate release. Potential economic impacts on agriculture, conservation concerns, and mixed public opinion regarding the species have highlighted the need to develop effective but humane management options. Fertility control might provide such a solution if a safe and environmentally benign contraceptive was available. The chemical 20,25-diazacholesterol dihydrochloride (diazacon) has previously been used to reduce reproductive output in avian species through reduction of blood cholesterol and cholesterol-dependent reproductive hormones. We orally dosed captive rose-ringed parakeets with a solution of either 9 mg/kg or 18 ...


Antibodies To Influenza And West Nile Viruses In Horses In Mexico, M. A. Loroño-Pino, J. A. Farfan-Ale, J. E. Garcia-Rejon, M. Lin, E. Rosado-Paredes, F. I. Puerto, A. Bates, J. J. Root, A. B. Franklin, H. J. Sullivan, B. J. Blitvich 2010 Laboratorio de Arbovirologia, Centro de Investigaciones Regionales ‘Dr Hideyo Noguchi’, Universidad Autónoma de Yucatán, Mérida, Yucatán, CP 97000, Mexico

Antibodies To Influenza And West Nile Viruses In Horses In Mexico, M. A. Loroño-Pino, J. A. Farfan-Ale, J. E. Garcia-Rejon, M. Lin, E. Rosado-Paredes, F. I. Puerto, A. Bates, J. J. Root, A. B. Franklin, H. J. Sullivan, B. J. Blitvich

USDA National Wildlife Research Center - Staff Publications

INFLUENZA A virus (IAV) (family Orthomyxoviridae) is a highly infectious respiratory pathogen of birds and mammals, including human beings and horses (Palese and Shaw 2007). The virus is classified into different subtypes based on the antigenic properties of the haemagglutinin (HA) and neuraminidase (NA) proteins. Sixteen HA subtypes (H1 to H16) and nine NA subtypes (N1 to N9) have been identified (Fouchier and others 2005). Two subtypes, H3N8 and H7N7, have been isolated from horses. The H7N7 subtype was first isolated from a horse in Czechoslovakia in 1956 (Prague/56) (Sovinova and others 1958), and the H3N8 subtype was first ...


Stream Bank Soil And Phosphorus Losses Within Grazed Pasture Stream Reaches In The Rathbun Watershed In Southern Iowa, Mustafa Tufekcioglu 2010 Iowa State University

Stream Bank Soil And Phosphorus Losses Within Grazed Pasture Stream Reaches In The Rathbun Watershed In Southern Iowa, Mustafa Tufekcioglu

Graduate Theses and Dissertations

Stream bank erosion within agricultural landscapes is a major pathway for non-point source sediment and phosphorus loading to receiving waters. The objectives of this study were to: 1) compare the effect of livestock stocking rate on sediment and phosphorus loss from stream bank erosion in the Rathbun Watershed in southern Iowa; 2) assess the relationship between stream stage and stream bank soil erosion rates, and 3) evaluate the impacts of current riparian land-uses and stream morphologic characteristics at the field and catchment scale on stream bank erosion. Stream bank erosion rates over three years were estimated using the erosion pin ...


Burn Severity And Whitebark Pine (Pinus Albicaulis) Regeneration In The North Cascades, Stephanie A. (Stephanie Annie) McDowell 2010 Western Washington University

Burn Severity And Whitebark Pine (Pinus Albicaulis) Regeneration In The North Cascades, Stephanie A. (Stephanie Annie) Mcdowell

WWU Graduate School Collection

Whitebark pine (Pinus albicaulis, Engelm.) is a long-lived and slow-growing high elevation tree and a key part of subalpine communities in the North Cascades, Washington State. Whitebark pine populations in Washington are declining because of an exotic fungus, white pine blister rust (Cronartium ribicola), and successional replacement due to fire exclusion. An increase in whitebark pine seedling density could help restore populations and accelerate the process of natural selection towards rust resistance. Where whitebark pine is firedependent, fire exclusion has impeded whitebark pine regeneration. The relationship between whitebark pine regeneration and burn severity was studied in the subalpine and timberline ...


Evaluation Of High-Latitude Boreal Forest Growth Using Satellite-Derived Vegetation Indices, Logan T. Berner 2010 Western Washington University

Evaluation Of High-Latitude Boreal Forest Growth Using Satellite-Derived Vegetation Indices, Logan T. Berner

WWU Graduate School Collection

Vegetation in northern high-latitudes plays an important role in energy exchange and carbon dynamics, thereby influencing regional and global climate. Vegetation indices derived from the space-borne Advanced Very High Resolution Radiometers (AVHRR) have suggested decreased photosynthetic activity during recent decades within some continental regions of the pan-arctic boreal forests. The purpose of this research was to determine associations between the normalized difference vegetation index (NDVI), as derived by both AVHRR and Moderate Resolution Imaging Spectroradiometers (MODIS), and inter-annual variations in radial stem growth in high-latitude coniferous forests. During 2008 and 2009, tree core samples were collected at 12 sites in ...


Food Habits Of Stunted And Non-Stunted White Perch (Marone Americana), Nathan J.C. Gosch, Jeffrey R. Stittle, Kevin L. Pope 2010 Nebraska Cooperative Fish and Wildlife Research Unit

Food Habits Of Stunted And Non-Stunted White Perch (Marone Americana), Nathan J.C. Gosch, Jeffrey R. Stittle, Kevin L. Pope

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

We studied food habits of white perch (Morone americana) from two populations with different stable states (stunted [Branched Oak Lake, Nebraska] and non-stunted [Pawnee Lake, Nebraska]) to determine if change in food habits of white perch is likely to occur in situations where a stunted while perch population is altered to a non-stunted state and vice versa. Three approaches were used to quantitatively describe seasonal (spring= March-May, summer= June-August, autumn = September-November) diets of white perch - 1) frequency of occurrence, 2) percentage of composition by volume, and 3) mean stomach fullness. White perch diets were dominated by cladocerans and dipterans in ...


Methods For Assessing Fish Populations, Kevin L. Pope, Steve E. Lochmann, Michael K. Young 2010 University of Nebraska-Lincoln

Methods For Assessing Fish Populations, Kevin L. Pope, Steve E. Lochmann, Michael K. Young

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Fisheries managers are likely to assess fish populations at some point during the fisheries management process. Managers that follow the fisheries management process (see Chapter 5) might find their knowledge base insufficient during the steps of problem identification or management action and must assess a population before appropriate actions can be taken. Managers will implement some type of assessment during the evaluation step as a means of measuring progress relative to objectives. Choosing how to assess a population is an important decision because managers strive to maximize their knowledge of a population while minimizing the time and money expended to ...


A Modelling Approach To Evaluate Potential Management Actions Designed To Increase Growth Of White Perch In A High-Density Population, Christopher J. Chizinski, Kevin L. Pope, G.R. Wilde 2010 Texas Tech University

A Modelling Approach To Evaluate Potential Management Actions Designed To Increase Growth Of White Perch In A High-Density Population, Christopher J. Chizinski, Kevin L. Pope, G.R. Wilde

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

A deterministic, age-structured population model was developed to simulate potential management scenarios designed to increase growth of individuals (quantified by maximum length) in a hypothetical population of white perch, Morone americana (Gmelin). Four scenarios were developed that included non-selective mortality of adult white perch, increased mortality of age groups most influential on population growth, increased age-0 mortality and inhibiting recruitment after spawning. The greatest increase in maximum length occurred with nonselective adult mortality when population biomass was reduced by 97%; lesser increases in maximum length were achieved with the other management scenarios. Populations returned to their original state after control ...


Risk Assessment: Simultaneously Prioritizing The Control Of Invasive Plant Species And The Conservation Of Rare Plant Species, Thaddeus K. Miller, Craig R. Allen, Wayne G. Landis, James W. Merchant 2010 Univeristy of Nebraska-Lincoln

Risk Assessment: Simultaneously Prioritizing The Control Of Invasive Plant Species And The Conservation Of Rare Plant Species, Thaddeus K. Miller, Craig R. Allen, Wayne G. Landis, James W. Merchant

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

Although the consequences of the homogenization of Earth’s flora and fauna are not well understood, experts agree that biological invasions pose hazards to rare species. As a result, there is a need for a systematic approach to assess risks from invasive species. The Relative Risk Model can be adapted to assess combinations of rare species, invasive species, and regions. It also can be applied to different taxonomic groups and at different spatial scales. This flexibility makes it a promising tool for invasive species risk assessment. We used the Relative Risk Model to quantify risks posed to endangered plant species ...


Evaluating Food Availability And Nest Predation Risk As Sources Of Bias In Aural Bird Surveys, Bruce A. Robertson, Richard L. Hutto, Joseph J. Fontaine 2010 University of Montana - Missoula

Evaluating Food Availability And Nest Predation Risk As Sources Of Bias In Aural Bird Surveys, Bruce A. Robertson, Richard L. Hutto, Joseph J. Fontaine

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

The use of aural surveys to estimate population parameters is widespread in avian studies.Despite efforts to increase the efficacy of this method, the potential for ecological context to bias population estimates remains largely unexplored. For example, food availability and nest predation risk can influence singing activity independent of density and, therefore, may bias aural estimates where these ecological factors vary systematically among habitats or other categories of ecological interest. We used a natural fire event in a mixed-conifer forest that experienced variation in fire severity (low, intermediate, and high) to determine if aural surveys produce accurate density estimates of ...


Metabolic Engineering For Production Of Biorenewable Fuels And Chemicals: Contributions Of Synthetic Biology, Laura R. Jarboe, Xueli Zhang, Xuan Wang, Jonathan C. Moore, K. T. Shanmugam, Lonnie O. Ingram 2010 Iowa State University

Metabolic Engineering For Production Of Biorenewable Fuels And Chemicals: Contributions Of Synthetic Biology, Laura R. Jarboe, Xueli Zhang, Xuan Wang, Jonathan C. Moore, K. T. Shanmugam, Lonnie O. Ingram

Chemical and Biological Engineering Publications

Production of fuels and chemicals through microbial fermentation of plant material is a desirable alternative to petrochemicalbased production. Fermentative production of biorenewable fuels and chemicals requires the engineering of biocatalysts that can quickly and efficiently convert sugars to target products at a cost that is competitive with existing petrochemical-based processes. It is also important that biocatalysts be robust to extreme fermentation conditions, biomass-derived inhibitors, and their target products. Traditional metabolic engineering has made great advances in this area, but synthetic biology has contributed and will continue to contribute to this field, particularly with next-generation biofuels. This work reviews the use ...


What Are The Consequences Of Consequentiality?, Joseph Herriges, Catherine L. Kling, Chih-Chen Liu, Justin Tobias 2010 Iowa State University

What Are The Consequences Of Consequentiality?, Joseph Herriges, Catherine L. Kling, Chih-Chen Liu, Justin Tobias

Economics Publications

We investigate the extent to which dichotomous choice referenda responses are shaped by whether the individual believes the survey itself will ultimately impact policy. Using survey data from the Iowa Lakes Project, we test this supposition. Specifically, we employ a Bayesian treatment effect model in which the degree of perceived consequentiality, measured as an ordinal response, is permitted to have a structural impact on willingness to pay (WTP) for a hypothetical environmental improvement. We test whether the estimated WTP distributions are the same for each value of the ordinal response.

In our survey data, a subsample of individuals were randomly ...


Distance Software: Design And Analysis Of Distance Sampling Surveys For Estimating Population Size, Len Thomas, Stephen T. Buckland, Eric A. Rexstad, Jeff L. Laake, Samantha Strindberg, Sharon L. Hedley, Jon R.B. Bishop, Tiago A. Marques, Kenneth P. Burnham 2010 Research Unit for Wildlife Population Assessment, Centre for Research into Ecological and Environmental Modelling, University of St. Andrews, St. Andrews KY16 9LZ, UK

Distance Software: Design And Analysis Of Distance Sampling Surveys For Estimating Population Size, Len Thomas, Stephen T. Buckland, Eric A. Rexstad, Jeff L. Laake, Samantha Strindberg, Sharon L. Hedley, Jon R.B. Bishop, Tiago A. Marques, Kenneth P. Burnham

Publications, Agencies and Staff of the U.S. Department of Commerce

1. Distance sampling is a widely used technique for estimating the size or density of biological populations. Many distance sampling designs and most analyses use the software Distance.

2. We briefly review distance sampling and its assumptions, outline the history, structure and capabilities of Distance, and provide hints on its use.

3. Good survey design is a crucial prerequisite for obtaining reliable results. Distance has a survey design engine, with a built-in geographic information system, that allows properties of different proposed designs to be examined via simulation, and survey plans to be generated.

4. A first step in analysis of ...


Resource Selection By Elk In An Agro-Forested Landscape Of Northwestern Nebraska, David M. Baasch, Justin W. Fischer, Scott E. Hygnstrom, Kurt C. Vercauteren, Andrew J. Tyre, Joshua J. Millspaugh, James W. Merchant, Jerry D. Volesky 2010 University of Nebraska - Lincoln

Resource Selection By Elk In An Agro-Forested Landscape Of Northwestern Nebraska, David M. Baasch, Justin W. Fischer, Scott E. Hygnstrom, Kurt C. Vercauteren, Andrew J. Tyre, Joshua J. Millspaugh, James W. Merchant, Jerry D. Volesky

Papers in Natural Resources

In recent years, elk have begun recolonizing areas east of the Rocky Mountains that are largely agroforested ecosystems composed of privately owned land where management of elk is an increasing concern due to crop and forage depredation and interspecific disease transmission. We used a Geographic Information System, elk use locations (n = 5013), random locations (n = 25,065), discrete-choice models, and information-theoretic methods to test hypotheses about elk resource selection in an agro-forested landscape located in the Pine Ridge region of northwestern Nebraska, USA. Our objectives were to determine landscape characteristics selected by female elk and identify publicly owned land within ...


Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra 2010 University of Central Florida

Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra

Electronic Theses and Dissertations

The soil seed bank plays a dynamic role in the regeneration of plant communities after natural and anthropogenic disturbance. In this thesis, I addressed how disturbances influence the vegetation and seed bank of Florida rosemary scrub. In Chapter One I evaluated changes in species composition and spatiotemporal pattern of the vegetation and seed bank along a gradient of disturbance. During the summers and winters of 2007-2009 percent ground cover and seed bank species composition were assessed among replicates of three vegetation types subjected to minimal, moderate, and extreme anthropogenic disturbance (native rosemary scrub, degraded scrub, and agriculturally improved pasture, respectively ...


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