1,363 research outputs found
Predicting spatial spread of rabies in skunk populations using surveillance data reported by the public
Background:
Prevention and control of wildlife disease invasions relies on the ability to predict spatio-temporal dynamics and understand the role of factors driving spread rates, such as seasonality and transmission distance. Passive disease surveillance (i.e., case reports by public) is a common method of monitoring emergence of wildlife diseases, but can be challenging to interpret due to spatial biases and limitations in data quantity and quality.
Methodology/Principal findings:
We obtained passive rabies surveillance data from dead striped skunks (Mephitis mephitis) in an epizootic in northern Colorado, USA. We developed a dynamic patch-occupancy model which predicts spatio-temporal spreading while accounting for heterogeneous sampling. We estimated the distance travelled per transmission event, direction of invasion, rate of spatial spread, and effects of infection density and season. We also estimated mean transmission distance and rates of spatial spread using a phylogeographic approach on a subsample of viral sequences from the same epizootic. Both the occupancy and phylogeographic approaches predicted similar rates of spatio-temporal spread. Estimated mean transmission distances were 2.3 km (95% Highest Posterior Density (HPD95): 0.02, 11.9; phylogeographic) and 3.9 km (95% credible intervals (CI95): 1.4, 11.3; occupancy). Estimated rates of spatial spread in km/year were: 29.8 (HPD95: 20.8, 39.8; phylogeographic, branch velocity, homogenous model), 22.6 (HPD95: 15.3, 29.7; phylogeographic, diffusion rate, homogenous model) and 21.1 (CI95: 16.7, 25.5; occupancy). Initial colonization probability was twice as high in spring relative to fall.
Conclusions/Significance:
Skunk-to-skunk transmission was primarily local (< 4 km) suggesting that if interventions were needed, they could be applied at the wave front. Slower viral invasions of skunk rabies in western USA compared to a similar epizootic in raccoons in the eastern USA implies host species or landscape factors underlie the dynamics of rabies invasions. Our framework provides a straightforward method for estimating rates of spatial spread of wildlife diseases
Let\u27s Get Ethical, A Look at the New Ethics Reform in the Commonwealth of Virginia
In April of 2015, the Virginia General Assembly returned to Richmond for its annual veto session, with the main focus on putting the finishing touches on ethics reform.1 After lengthy debate and a number of amendments, the omnibus ethics bill passed the House and the Senate unanimously. House and Senate Members from both political parties touted the accomplishment as a significant step forward, as did Governor McAuliffe who called the legislation a “victory for transparency and accountability.”
This Article will argue the cases of Delegate Phil Hamilton and former Governor Bob McDonnell provide a framework for analyzing whether the new statutory scheme is likely to prove effective in preventing undue influence and corruption in state government. Part II outlines the cases of Dele- gate Hamilton and Governor McDonnell in detail. Part III discusses ethics reform in Virginia including legislation passed in the 2015 General Assembly session. Part IV concludes the article
Efficiency of different spatial and temporal strategies for reducing vertebrate pest populations
Understanding effectiveness of control strategies of pest species is fundamental for planning efficient and cost-effective management programs. In addition to culling rates, there are many potential factors that can determine efficiency of different management strategies, including demographic processes such as immigration rates, birth dynamics, and spatial ecology. We developed a stochastic, data-based simulation model of feral swine population dynamics which accounted for social dynamics in space. We tested the impacts of different spatio-temporal management strategies (i.e., culling rates, timing of culling during the year, spatial pattern of culling and strength of a barrier to immigration) on population response and efficiency. The spatial culling strategy dramatically impacted efficiency of control – using zonation required removal of fewer pigs (up to 46% less) to achieve similar reductions compared with other spatial strategies. Also, our spatially-explicit model predicted that lower culling intensities could be used to achieve population reductions when zonation was applied relative to predictions from harvesting theory based on simple logistic models. As culling intensity increased (≥50% of target population annually) and the target population reached low density (\u3c5% of original density), effects of spatial strategy became less pronounced relative to immigration barrier effects. Lastly, for the same level of moderate culling effort, prioritization of culling during the low-birthing period generally resulted in faster population reduction to near zero abundance relative to prioritization during the high-birthing period, or spreading the work over a year period, but the significance of this effect depended on the spatial culling strategy and culling intensity. Our results imply that continually updating knowledge of current abundance during management may not only be important for determining culling quotas, but also for updating and optimizing management strategies. When the management goal is maximum population control, consideration of birth and spatial dynamics can increase return on management effort and bring to light management inefficiencies
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BIBFRAME beginnings at UT Austin
Slides from a panel discussion presented at the 2016 Texas Conference on Digital Libraries Special Forum: Exploring Linked Data for Libraries, which took place May 24, 2016.Staff from UT Libraries, the Harry Ransom Center, and the Tarlton Law Library have been collaborating in discussion group activities during the last year to develop knowledge and skills in anticipation of life after MARC, investigating the brave new world of linked data in libraries with a focus on the Library of Congress Bibliographic Framework (BIBFRAME) initiative.
Our group efforts to better understand BIBFRAME and linked data for libraries include in-depth discussions of current literature, webcasts, and presentations; strategic application of Zepheira’s Practical Practitioner training; and hands-on experimentation transforming local metadata in various formats for various resource types to BIBFRAME. Our analysis of the resulting transformations has helped us gain insight on mapping complexities, data loss, false transformations, potential new metadata displays, and the limitations of the tools involved. The experimentation process overall has afforded us the opportunity to ask targeted questions about what is needed to move towards linked data and to gain a better view of the frontier of Technical Services staff skillsets.
In this panel presentation, we’ll share details about our approaches to maximizing the group learning experience, and lessons learned from grappling with new concepts, data models, terminology, and tools. Representatives from our experimentation teams will report on the initial experience of transforming MARC and non-MARC data sets to BIBFRAME, and what we see as emerging questions and next steps.UT Librarie
Interspecific oral rabies vaccine bait competition in the Southeast United States
The United States Department of Agriculture’s National Rabies Management Program (NRMP) has coordinated the use of oral rabies vaccination (ORV) to control the spread of raccoon rabies virus variant west of the Appalachian Mountains since 1997. Working with state and local partners, the NRMP deploys ORV baits containing a rabies vaccine, primarily targeting raccoon populations (Procyon lotor). Bait competition between raccoons and non-target species may limit the effectiveness of ORV programs, but the extent of bait competition remains poorly quantified, particularly in the southeastern United States. We placed placebo ORV baits in bottomland hardwood (n = 637 baits) and upland pine (n = 681 baits) habitats in South Carolina, USA during August- December 2019 and used remote cameras to examine bait competition between raccoons and non-target species. The estimated proportion of bait consumed by raccoons was 18.8 ± 2.1% in bottomland hardwood and 11.6 ± 2.1% in upland pine habitats. Vertebrate competition appeared to have a minimal effect on raccoon uptake as estimated consumption did not exceed 5% for any species or 8% of bait uptake events cumulatively. We estimated that raccoons were the primary consumer of baits in bottomland hardwood, whereas invertebrates were the primary consumer in upland pine (26.7 ± 1.3% of baits). Our results indicate a need to closely consider the effects of invertebrates on bait consumption to minimize their potential impact on ORV bait uptake by target species. Uptake probabilities by raccoons were relatively low but not primarily driven by competition with vertebrates. As such, strategies to increase the specificity of raccoon uptake may be needed to enhance the effectiveness of ORV baiting programs
Costs and effectiveness of damage management of an overabundant species (\u3ci\u3eSus scrofa\u3c/i\u3e) using aerial gunning
Context. Management of overabundant or invasive species is a constant challenge because resources for management are always limited and relationships between management costs, population density and damage costs are complex and difficult to predict. Metrics of management success are often based on simple measures, such as counts, which may not be indicative of impacts on damage reduction or cost-effectiveness under different management plans.
Aims. The aims of this study were to evaluate the effectiveness of aerial gunning for the management of wild pigs (Sus scrofa), and to evaluate how cost-effectiveness would vary under different relationships between levels of damage and densities of wild pigs.
Methods. Repeated reduction events were conducted by aerial gunning on three consecutive days at three study sites. Using a removal model, the proportion of the population removed by each flight was estimated and population modelling was used to show the time it would take for a population to recover. Three possible damage–density relationships were then used to show the level of damage reduction (metric of success) from different management intensities and levels of population recovery, and these relationships were expressed in terms of total costs (including both damage and management costs).
Key results. Populations were typically reduced by ~31% for the first flight, ~56% after two flights and ~67% after three flights. When the damage relationship suggests high damage even at low densities, the impact of one, two or three flights would represent a reduction in damage of 2%, 19% and 60% respectively after 1 year. Different damage relationships may show considerable damage reduction after only one flight. Removal rates varied by habitat (0.05 per hour in open habitats compared with 0.03 in shrubby habitats) and gunning team (0.03 versus 0.05).
Conclusions. Monitoring the efficacy of management provides critical guidance and justification for control activities. The efficacy of different management strategies is dependent on the damage–density relationship and needs further study for effective evaluation of damage reduction efforts.
Implications. It is critically important to concurrently monitor density and damage impacts to justify resource needs and facilitate planning to achieve a desired damage reduction goal
RACCOON (\u3ci\u3ePROCYON LOTOR\u3c/i\u3e) RESPONSE TO ONTARIO RABIES VACCINE BAITS (ONRAB) IN ST. LAWRENCE COUNTY, NEW YORK, USA
Oral rabies vaccination (ORV) campaigns have been conducted annually in the US over the past two decades to prevent raccoon (Procyon lotor) rabies, which is enzootic along the eastern region of the country from southeastern Canada to Alabama. Because raccoon rabies has been eliminated from neighboring Canadian provinces, continued detection of the variant in the US is of concern due to the potential for infected raccoons to cross the border via the St. Lawrence River. Ontario Rabies Vaccine Baits (ONRAB) containing a live, recombinant human adenovirus expressing the rabies virus glycoprotein have been under experimental use in the US since 2011. We distributed ONRAB in St. Lawrence County, New York, from 2013 to 2015 as part of field trials to evaluate serologic responses in raccoons. Prior to ONRAB distribution, rabies virus neutralizing antibody (RVNA) seroprevalence in raccoons was 45.2% (183 of 405) and increased to 57.7% (165 of 286) after 3 yr of ONRAB baiting. Postbait RVNA seroprevalence increased each year, with a lower response observed in juvenile compared with adult raccoons. The pre-ONRAB seroprevalence detected in 2013 was relatively high and was likely impacted both by elevated rabies activity in the county and the use of ORV with a different vaccine bait for 14 consecutive years prior to our study. Tetracycline biomarker prevalence increased from 1.4% prior to ONRAB baiting to 51.3% from 2013 to 2015, demonstrating bait palatability to raccoons. These data complemented related field trials conducted in West Virginia and the northeastern US
Exercise augments the nocturnal prolactin rise in exercise-trained men
The objective of this study was to profile over a 24 h period the prolactin responses of exercise-trained men on a day involving rest with no exercise in comparison to a day involving exercise training sessions
Detection and persistence of environmental DNA from an invasive, terrestrial mammal
Invasive Sus scrofa, a species commonly referred to as wild pig or feral swine, is a destructive invasive species with a rapidly expanding distribution across the United States. We used artificial wallows and small waterers to determine the minimum amount of time needed for pig eDNA to accumulate in the water source to a detectable level. We removed water from the artificial wallows and tested eDNA detection over the course of 2 weeks to understand eDNA persistence. We show that our method is sensitive enough to detect very low quantities of eDNA shed by a terrestrial mammal that has limited interaction with water. Our experiments suggest that the number of individuals shedding into a water system can affect persistence of eDNA. Use of an eDNA detection technique can benefit management efforts by providing a sensitive method for finding even small numbers of individuals that may be elusive using other methods
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