Does Efficient Irrigation Technology Lead to Reduced Groundwater Extraction?: Empirical Evidence

Policies that encourage the use of more efficiency irrigation technology are often viewed as effective, politically feasible methods to reduce the consumptive use of water for agricultural production. Despite their widespread use, these policies have not been subject to empirical evaluation. In this article, we evaluate the effect on groundwater extraction of a widespread conversion from traditional center pivot irrigation systems to higher efficiency dropped-nozzle center pivot systems that has occurred in western Kansas. State and national cost-share programs subsidized the conversion. We find that the programs have not had the intended effect; the shift to more efficient irrigation technology has not decreased the amount of water applied to a given crop, and has actually increased groundwater extraction through changing cropping patterns.irrigation efficiency, groundwater management, irrigation technology, Environmental Economics and Policy, Land Economics/Use,

Risk factors associated with Rift Valley fever epidemics in South Africa in 2008-11.

Rift Valley fever (RVF) is a zoonotic and vector-borne disease, mainly present in Africa, which represents a threat to human health, animal health and production. South Africa has experienced three major RVF epidemics (1950-51, 1973-75 and 2008-11). Due to data scarcity, no previous study has quantified risk factors associated with RVF epidemics in animals in South Africa. Using the 2008-11 epidemic datasets, a retrospective longitudinal study was conducted to identify and quantify spatial and temporal environmental factors associated with RVF incidence. Cox regressions with a Besag model to account for the spatial effects were fitted to the data. Coefficients were estimated by Bayesian inference using integrated nested Laplace approximation. An increase in vegetation density was the most important risk factor until 2010. In 2010, increased temperature was the major risk factor. In 2011, after the large 2010 epidemic wave, these associations were reversed, potentially confounded by immunity in animals, probably resulting from earlier infection and vaccination. Both vegetation density and temperature should be considered together in the development of risk management strategies. However, the crucial need for improved access to data on population at risk, animal movements and vaccine use is highlighted to improve model predictions

Effects of “The Blob” on profitability in the West Coast Pacific whiting fishery

The Pacific whiting fishery is one of the most economically important fisheries on the West Coast of the United States, with around $50 million in annual landings. In general, the fishery is highly profitable. “The Blob”, or the large mass of warm water in the Northeastern Pacific Ocean, was first detected in 2013 and persisted through mid-2016. It was the “largest marine heatwave ever recorded”. The Blob has been associated with low primary productivity, an unprecedented toxic algal bloom that caused the largest-ever closure of the Dungeness crab fishery, unusual sea bird, whale, and sea lion mortality events, and warm-water species being detected in the northern California Current region. These anomalous ocean conditions had large and unexpected effect on the West Coast Pacific whiting fishery as well. This paper evaluates the socioeconomic impacts that The Blob had on the Pacific whiting fishery in 2104 and, primarily, 2015. Vessel-level profitability was between 41% and 76% lower than in 2015. We explore the drivers of this decline. Attainment of the TAC by each sector was extremely low in 2015; attainment is normally near 100% in the Pacific whiting fishery. CPUE was between 75% and 84% lower than normal in the second half of 2015, leading to higher search costs and leading to some vessels to stop fishing completely (the number of hauls by the at-sea mothership sector was 55% lower than normal in 2015). We quantify the effects of each factor on annual profitability and economic stability

Risk Taking and Fishing Safety: Evaluation Efforts by the National Marine Fisheries Service

When fisheries management creates the incentive to “race for fish”, a fishing season can be reduced to only a few days and involve around-the-clock fishing in life-threatening weather conditions. Catch shares management, or the individual allocation of tradeable fishing quota, can improve safety by reducing economic incentives to fish as rapidly as possible. This presentation will discuss the modeling framework and established research that will serve as the basis for a series of case studies and a meta-analysis. The framework relies on identifying behavior that is "risky", and modeling the effects that the policy has on risk-taking. In this case, we use the propensity to fish in poor weather conditions as a proxy for risk. One published case study shows that catch shares reduced fishing in poor weather by 79%

Climate Change and Fisher Behavior in the Bering Sea Pollock Fishery

One component of the Bering Sea Integrated Ecosystem Research Project (BSIERP) is a spatial economic model that predicts changes in fishing activity in the Bering Sea pollock fishery that may result from climate change. Models such as the one employed here have been used in the Bering Sea and elsewhere to model how fishers make decisions about where to fish. Commercial fishers choose different areas to fish based on observable and unobservable characteristics of the area and the fisher. We commonly model location choice as a function of the expected revenue in an area, fuel and fish prices, distance to an area, vessel characteristics, and to a more limited degree, institutional and environmental conditions. In the Bering Sea pollock fishery, climate variables affect many aspects of the fishing decision. Key among these aspects is the role that climate has on fish location and abundance and the impact that weather plays in daily participation and location choices for smaller vessels. In this paper, we develop a model of the AFA pollock catcher processor fleet. The spatial economic model can incorporate climate data (e.g., ice cover, SST, wind) into the model, permitting us to determine the relative impact of observable contemporaneous environmental conditions on location choices. We also develop a framework to include predictions of changing pollock abundance in the model, which will allow us to estimate fisher responses to scenarios developed by oceanographic and ecosystem modelers involved in Bering Sea project. We also discuss similar modeling of the other sectors of the pollock fishery and the Pacific cod fishery

Modelling the transmission dynamics of H9N2 avian influenza viruses in a live bird market

H9N2 avian influenza viruses (AIVs) are a major concern for the poultry sector and human health in countries where this subtype is endemic. By fitting a model simulating H9N2 AIV transmission to data from a field experiment, we characterise the epidemiology of the virus in a live bird market in Bangladesh. Many supplied birds arrive already exposed to H9N2 AIVs, resulting in many broiler chickens entering the market as infected, and many indigenous backyard chickens entering with pre-existing immunity. Most susceptible chickens become infected within one day spent at the market, owing to high levels of viral transmission within market and short latent periods, as brief as 5.3 hours. Although H9N2 AIV transmission can be substantially reduced under moderate levels of cleaning and disinfection, effective risk mitigation also requires a range of additional interventions targeting markets and other nodes along the poultry production and distribution network

Transmission potential of Rift Valley fever virus over the course of the 2010 epidemic in South Africa.

A Rift Valley fever (RVF) epidemic affecting animals on domestic livestock farms was reported in South Africa during January-August 2010. The first cases occurred after heavy rainfall, and the virus subsequently spread countrywide. To determine the possible effect of environmental conditions and vaccination on RVF virus transmissibility, we estimated the effective reproduction number (Re) for the virus over the course of the epidemic by extending the Wallinga and Teunis algorithm with spatial information. Re reached its highest value in mid-February and fell below unity around mid-March, when vaccination coverage was 7.5%-45.7% and vector-suitable environmental conditions were maintained. The epidemic fade-out likely resulted first from the immunization of animals following natural infection or vaccination. The decline in vector-suitable environmental conditions from April onwards and further vaccination helped maintain Re below unity. Increased availability of vaccine use data would enable evaluation of the effect of RVF vaccination campaigns

Status Quo of Progress Testing in Veterinary Medical Education and Lessons Learned

Progress testing is an assessment tool for longitudinal measurement of increase in knowledge of a specific group, e.g., students, which is well-known in medical education. This article gives an overview of progress testing in veterinary education with a focus on the progress test of the German-speaking countries. The "progress test veterinary medicine" (PTT) was developed in 2013 as part of a project by the Competence Centre for E-Learning, Didactics and Educational Research in Veterinary Medicine-a project cooperation of all German-speaking institutes for veterinary medicine in Germany, Austria, and Switzerland. After the end of the project, the PTT was still continued at six locations, at each of the five German schools for veterinary medicine and additionally in Austria. Further changes to the PTT platform and the analysis were carried out to optimize the PTT for continuing to offer the test from 2017 to 2019. The PTT is an interdisciplinary, formative electronic online test. It is taken annually and is composed of 136 multiple-choice single best answer questions. In addition, a "don't know" option is given. The content of the PTT refers to the day 1 competencies described by the European Association of Establishments for Veterinary Education. The platform Q-Exam (R) Institutions (IQuL GmbH, Bergisch Gladbach, Germany) is used for creating and administrating the PTT questions, the review processes and organizing of the online question database. After compiling the test by means of a blueprint, the PTT file is made available at every location. After the last PTT in 2018, the link to an evaluation was sent to the students from four out of these six partner Universities. The 450 analyzed questionnaires showed that the students mainly use the PTT to compare their individual results with those of fellow students in the respective semester. To conclude our study, a checklist with our main findings for implementing progress testing was created