Protocols for listing threatened species can forecast extinction

Risk‐ranking protocols are used widely to classify the conservation status of the world's species. Here we report on the first empirical assessment of their reliability by using a retrospective study of 18 pairs of bird and mammal species (one species extinct and the other extant) with eight different assessors. The performance of individual assessors varied substantially, but performance was improved by incorporating uncertainty in parameter estimates and consensus among the assessors. When this was done, the ranks from the protocols were consistent with the extinction outcome in 70–80% of pairs and there were mismatches in only 10–20% of cases. This performance was similar to the subjective judgements of the assessors after they had estimated the range and population parameters required by the protocols, and better than any single parameter. When used to inform subjective judgement, the protocols therefore offer a means of reducing unpredictable biases that may be associated with expert input and have the advantage of making the logic behind assessments explicit. We conclude that the protocols are useful for forecasting extinctions, although they are prone to some errors that have implications for conservation. Some level of error is to be expected, however, given the influence of chance on extinction. The performance of risk assessment protocols may be improved by providing training in the application of the protocols, incorporating uncertainty in parameter estimates and using consensus among multiple assessors, including some who are experts in the application of the protocols. Continued testing and refinement of the protocols may help to provide better absolute estimates of risk, particularly by re‐evaluating how the protocols accommodate missing data.     

Ecological Risk Assessment for Terrestrial Ecosystems: The Summary of Discussions and Recommendations from the Adelaide Workshop (April 2004)

The Ecological Risk Assessment (ERA) workshop focused on the anthropogenic contaminants in the terrestrial environment, addressing various components of the ERA process. These included sources, exposure pathways, bioavailability, and toxicity to receptor organisms as well as risk communication. It was concluded that although the overseas experience on ERA for terrestrial ecosystems (e.g., International Standards or guidelines from the European Union and the United States) is very useful, it is not directly applicable to Australia due to the differences in receptor organisms, contaminants, soil, and environmental conditions. Workshop discussions stressed on the need for making ERA locally relevant (in terms of choice of receptor organisms, sampling strategy, and bioavailability considerations). The workshop discussions highlighted the need of better appreciation of both the similarities and the clear differences between aquatic and terrestrial ERAs. The availability of reliable data, problems with databases, estimation of bioavailability, and extrapolations from laboratory to field were noted among the key limitations. ERA—being inherently complex and involving a range of environmental compartments, target receptor, and exposure pathways—at a minimum requires a multidisciplinary approach to address the complexities. Bringing a multidisciplinary team together often proves a major challenge in ERA. The delegates called for continued efforts in this area and formation of a network or working group in Australia.     

Bioavailability of Soil-borne Chemicals: A Regulatory Perspective

U.S. Environmental Protection Agency (USEPA) risk assessment guidance documents dating back to 1989 have articulated the principles for incorporating information on bioavailability into the risk assessment process. However, in the interim period both the methods for obtaining media or route specific measures of bioavailability and the corresponding guidance to incorporate these data have languished. Presently, USEPA is developing guidance to address both of these concerns. This article outlines the broad framework for systematically evaluating the role of bioavailability in site-specific risk assessment from a regulatory perspective. At the same time, in appreciation of the vast horizon of uncharted territory ahead, the focus of USEPA's draft guidance, and consequently this report, is on bioavailability adjustments for soil-borne metals. The article describes a two-stage process. The first stage outlines a paradigm for screening sites to determine if generating site-specific data on the bioavailability of a metal in soil is of technical utility and economically justifiable. The second stage focuses on the collection, analysis, and incorporation of these data into the risk assessment for decision-making purposes.     

An economic theory of patient decision-making

Patient autonomy, as exercised in the informed consent process, is a central concern in bioethics. The typical bioethicist's analysis of autonomy centers on decisional capacity--finding the line between autonomy and its absence. This approach leaves unexplored the structure of reasoning behind patient treatment decisions. To counter that approach, we present a microeconomic theory of patient decision-making regarding the acceptable level of medical treatment from the patient's perspective. We show that a rational patient's desired treatment level typically departs from the level yielding an absence of symptoms, the level we call ideal. This microeconomic theory demonstrates why patients have good reason not to pursue treatment to the point of absence of physical symptoms. We defend our view against possible objections that it is unrealistic and that it fails to adequately consider harm a patient may suffer by curtailing treatment. Our analysis is fruitful in various ways. It shows why decisions often considered unreasonable might be fully reasonable. It offers a theoretical account of how physician misinformation may adversely affect a patient's decision. It shows how billing costs influence patient decision-making. It indicates that health care professionals' beliefs about the 'unreasonable' attitudes of patients might often be wrong. It provides a better understanding of patient rationality that should help to ensure fuller information as well as increased respect for patient decision-making.     

Taking a trip to the shelf: Behavioral decisions are mediated by the proximity to foraging habitats in the black‐legged kittiwake

For marine top predators like seabirds, the oceans represent a multitude of habitats regarding oceanographic conditions and food availability. Worldwide, these marine habitats are being altered by changes in climate and increased anthropogenic impact. This is causing a growing concern on how seabird populations might adapt to these changes. Understanding how seabird populations respond to fluctuating environmental conditions and to what extent behavioral flexibility can buffer variations in food availability can help predict how seabirds may cope with changes in the marine environment. Such knowledge is important to implement proper long‐term conservation measures intended to protect marine predators. We explored behavioral flexibility in choice of foraging habitat of chick‐rearing black‐legged kittiwakes Rissa tridactyla during multiple years. By comparing foraging behavior of individuals from two colonies with large differences in oceanographic conditions and distances to predictable feeding areas at the Norwegian shelf break, we investigated how foraging decisions are related to intrinsic and extrinsic factors. We found that proximity to the shelf break determined which factors drove the decision to forage there. At the colony near the shelf break, time of departure from the colony and wind speed were most important in driving the choice of habitat. At the colony farther from the shelf break, the decision to forage there was driven by adult body condition. Birds furthermore adjusted foraging behavior metrics according to time of the day, weather conditions, body condition, and the age of the chicks. The study shows that kittiwakes have high degree of flexibility in their behavioral response to a variable marine environment, which might help them buffer changes in prey distribution around the colonies. The flexibility is, however, dependent on the availability of foraging habitats near the colony.     

‘They should hire the one with the best score’: White sensitivity to qualification differences in affirmative action hiring decisions

This paper uses innovative survey questions from the 1998 Detroit Area Study to examine how whites communicate their views about racial matters across three affirmative action hiring scenarios. Results suggest that most whites prefer explanations for not hiring blacks based on the abstract and decontextualized application of the principles of liberalism. Justifications that were initially offered emphasizing qualification thresholds, broad criteria, and contextual concerns, usually in support of hiring the black applicant, were largely withdrawn when the scenario was changed from one with equal scores to one with scores slightly favouring the white applicant. Concrete and contextualized concerns about workforce homogeneity and the slightness of score differences were raised in a conciliatory manner when scores were equal, but then were seldom maintained when scores favoured the white candidate. Whites also more readily voiced opposition when the reason for hire was changed from ‘diversity’ to ‘make up for past discrimination’, offering ‘reasonable’ responses about ‘the past is the past’ that don't deny concrete historical events, but dismiss their connection to today's racial order. Taken together, the evidence suggests that the language of universalism and minimization of racism allow most whites to communicate their views about affirmative action using rhetorical strategies that seem reasonable and moral.     

The development and nature of the ordinary/extraordinary means distinction in the Roman Catholic tradition

In the Roman Catholic tradition the nature of the ordinary/extraordinary means distinction is best understood in light of its historical development. The moralist tradition that reared and nurtured this distinction implicitly developed a set of general criteria to distinguish the extraordinary from the ordinary. These criteria, conjoined with the context within which they were understood, can play an important role in refereeing the contemporary debate over the aggressiveness of medical treatment and the extent of one's moral obligation.     

To what extent can ecosystem services motivate protecting biodiversity?

Society increasingly focuses on managing nature for the services it provides people rather than for the existence of particular species. How much biodiversity protection would result from this modified focus? Although biodiversity contributes to ecosystem services, the details of which species are critical, and whether they will go functionally extinct in the future, are fraught with uncertainty. Explicitly considering this uncertainty, we develop an analytical framework to determine how much biodiversity protection would arise solely from optimising net value from an ecosystem service. Using stochastic dynamic programming, we find that protecting a threshold number of species is optimal, and uncertainty surrounding how biodiversity produces services makes it optimal to protect more species than are presumed critical. We define conditions under which the economically optimal protection strategy is to protect all species, no species, and cases in between. We show how the optimal number of species to protect depends upon different relationships between species and services, including considering multiple services. Our analysis provides simple criteria to evaluate when managing for particular ecosystem services could warrant protecting all species, given uncertainty. Evaluating this criterion with empirical estimates from different ecosystems suggests that optimising some services will be more likely to protect most species than others.     

Effects of macroparasites on the energy allocation of reproducing small mammals

Reproduction, including lactation, is the most costly activity in terms of energy expenditure in female mammals. Consequently, the energy requirements of the reproducing female may not be met at this time, especially if other energy demanding activities are occurring concomitantly. Such activities could be the activation and maintenance of an immune system in response to parasitic infestation. These protective processes are energetically demanding and require trade-off decisions among competing energy demands. In the case of a reproducing mammal, the trade-offs occur mainly between defence against parasites and reproductive costs of the host. In this paper, I discuss the effects of macroparasites on the energy allocation of reproducing small mammals.