Analysis of Regional Scale Risk of Whirling Disease in Populations of Colorado and Rio Grande Cutthroat Trout Using a Bayesian Belief Network Model

Introduction and spread of the parasite Myxobolus cerebralis, the causative agent of whirling disease, has contributed to the collapse of wild trout populations throughout the intermountain west. Of concern is the risk the disease may have on conservation and recovery of native cutthroat trout. We employed a Bayesian belief network to assess probability of whirling disease in Colorado River and Rio Grande cutthroat trout (Oncorhynchus clarkii pleuriticus and Oncorhynchus clarkii virginalis, respectively) within their current ranges in the southwest United States. Available habitat (as defined by gradient and elevation) for intermediate oligochaete worm host, Tubifex tubifex, exerted the greatest influence on the likelihood of infection, yet prevalence of stream barriers also affected the risk outcome. Management areas that had the highest likelihood of infected Colorado River cutthroat trout were in the eastern portion of their range, although the probability of infection was highest for populations in the southern, San Juan subbasin. Rio Grande cutthroat trout had a relatively low likelihood of infection, with populations in the southernmost Pecos management area predicted to be at greatest risk. The Bayesian risk assessment model predicted the likelihood of whirling disease infection from its principal transmission vector, fish movement, and suggested that barriers may be effective in reducing risk of exposure to native trout populations. Data gaps, especially with regard to location of spawning, highlighted the importance in developing monitoring plans that support future risk assessments and adaptive management for subspecies of cutthroat trout.     

The Predicament of Population Aging: A Review Essay*

Ken Dychtwald, Age Power: How the 21st Century Will Be Ruled by the New Old Richard Leete (ed.), Dynamics of Values in Fertility Change Donald T. Critchlow, Intended Consequences: Birth Control, Abortion, and the Federal Government in Modern America Bernard Jeune and James W. Vaupel (eds.), Validation of Exceptional Longevity     

History lessons: inequality,diversity and the national curriculum

This article explores the continued importance of teaching a diverse curriculum at a time when issues of racial and ethnic equality and diversity have been increasingly sidelined in the political discussion around ‘British’ values and identities, and how these should be taught in schools. The 2014 History National curriculum, in particular, provoked widespread controversy around what British history is, who gets included in this story and how best to engage young people in increasingly diverse classrooms with the subject. The new curriculum provides both opportunities for, and constraints on, addressing issues of racial and ethnic equality and diversity, but how these are put into practice in an increasingly fragmented school system remains less clear. Drawing on the findings of two research projects in schools across England and Wales, this article examines the challenges and opportunities facing teachers and young people in the classroom in the teaching and learning of diverse British histories. We argue that it is not only the content of what children and young people are taught in schools that is at issue, but how teachers are supported to teach diverse curricula effectively and confidently.     

Ascertaining the effect of planned organizational change on the work environment

In a dynamic environment, organizations often are required to effect major changes in operations. The success of such changes invariably depends upon numerous factors one of which is how the change affects the work environment. Therefore, in planning organizational change it is important to consider the work environment and to objectively evaluate changes in the work environment in a timely fashion so that corrective actions may be formulated if needed. Such framing and monitoring of the organizational change facilitates successful implementation of the organizational change. This paper suggests a measure which may be used in evaluating an organization's work environment. A case is discussed.     

Growing the Volunteer Pool: Identifying Non-Volunteers Most Likely to Volunteer

There are ongoing management and societal challenges affecting volunteering participation. These place a premium on organizations identifying individuals that currently do not volunteer but have the willingness and capacity to do so, the “Potentials”. Supplementing the limited non-volunteer literature, we seek to quantify this potential volunteer pool using constructs aligned to the willingness, capability and availability dimensions from Meijs et al.’s (Volunt Action 8:36–54, 2006) volunteerability framework. Using binary logistic regression testing with a nationally representative sample of Australian volunteers and non-volunteers, we found partial support for the framework’s willingness and capability dimensions determining volunteer status. We then applied a predictive equation to the non-volunteer sample to calculate their percentage likelihood of volunteering, to identify a cohort of “Potential” volunteers. Further testing revealed statistically significant differences between this cohort compared to other non-volunteers based on various interventions for promoting volunteering. The implications of our novel study and an associated research agenda are discussed.