The consequences of climate-driven stop-over sites changes on migration schedules and fitness of Arctic geese

1. How climatic changes affect migratory birds remains difficult to predict because birds use multiple sites in a highly interdependent manner. A better understanding of how conditions along the flyway affect migration and ultimately fitness is of paramount interest.

2. Therefore, we developed a stochastic dynamic model to generate spatially and temporally explicit predictions of stop-over site use. For each site, we varied energy expenditure, onset of spring, intake rate and day-to-day stochasticity independently. We parameterized the model for the migration of pink-footed goose Anser brachyrhynchus from its wintering grounds in Western Europe to its breeding grounds on Arctic Svalbard.

3. Model results suggested that the birds follow a risk-averse strategy by avoiding sites with comparatively high energy expenditure or stochasticity levels in favour of sites with highly predictable food supply and low expenditure. Furthermore, the onset of spring on the stop-over sites had the most pronounced effect on staging times while intake rates had surprisingly little effect.

4. Subsequently, using empirical data, we tested whether observed changes in the onset of spring along the flyway explain the observed changes in migration schedules of pink-footed geese from 1990 to 2004. Model predictions generally agreed well with empirically observed migration patterns, with geese leaving the wintering grounds earlier while considerably extending their staging times in Norway.

Stoichiometry of endothermy : shifting the quest from nitrogen to carbon

For many animals, notably herbivores, plants are often an inadequate food source given the low content of protein and high content of C-rich material. This conception is mainly based on studies on ectotherms. The validity of this conception for endotherms is unclear given their much higher carbon requirements for maintenance energy metabolism than ectotherms. Applying stoichiometric principles, we hypothesized that endotherms can cope with diets with much higher (metabolizable) carbon to nitrogen ratios than ectotherms. Using empirical data on birds, eutherian mammals, marsupials and reptiles, we compiled and compared measurements and allometric equations for energy metabolism as well as nitrogen requirements. Our analysis supports our hypothesis that plants, and especially their leaves, are generally sufficiently rich in nitrogen to fulfil protein demands in endotherms, at least during maintenance conditions, but less so in ectotherms. This has important implications with respect to community functioning and the evolution of endothermy.

Intake rates, stochasticity, or onset of spring : what aspects of food availability affect spring migration patterns in Pink-footed Geese Anser brachyrhynchus?

Long-distance bird migration consists of several flight episodes interrupted by a series of resting and refuelling periods on stopover sites. We assessed the role of food availability as the determinant of staging decisions focusing on the following three aspects of food availability: intake rates, stochasticity in intake rates and onset of spring. Using stochastic dynamic modelling, we investigated their impact on staging times and expected fitness. Subsequently, we compared relations in the use of the stopover sites as predicted by the model with empirical data of the Svalbard-breeding population of Pink-footed Goose Anser brachyrhynchus collected in the period 1990–2002. Our results indicate that, for the case of Pink-footed Geese, spring phenology determines a major part of the migration schedule. In contrast to our expectations, intake rates were generally only of minor importance; however, when approaching the breeding grounds their significance increased. Expected fitness at arrival on the breeding grounds showed that the geese can compensate for changes in a broad range of food availability and also cope with varying degrees of stochasticity. However, declining intake rates at the last stopover site or very late onsets of spring clearly decreased fitness. As predicted by the model, the use of stopover sites was interdependent – from empirical data we derived negative relationships between the staging durations of subsequent sites. These results lend credit to an integrated spatially explicit approach focussing on multiple stopover site characteristics when attempting to improve our understanding of bird migration.

Exhaled air temperature as a function of ambient temperature in flying and resting ducks

Exhaled air temperature (T exh) has a paramount effect on respiratory water loss during flight. For migratory birds, low T exh potentially reduces water loss and increases flight range. However, only three studies provide empirical data on T exh during flight. The aim of this study was to record T exh of birds during rest and flight at a range of controlled ambient temperatures (T amb). One wigeon and two teal flew a total of 20 times in a wind tunnel at T amb ranging from 1° to 24°C. T exh during flight did not differ between the two species and was strongly correlated with T amb (T exh=1.036 T amb + 13.426; R²=0.58). In addition, body temperature had a weak positive effect on T exh. At a given T amb, T exh was about 5°C higher during flight than at rest.

Productive pedagogies : is it an intelligible language for preservice teachers?

Australian teacher educators and teachers have become increasingly familiar with the notion of ‘Productive Pedagogies’, itself the product of longitudinal research on school reform recently undertaken in Queensland, Australia (Lingard et al., 2001a, , 2001b) . One of its strengths has been its efficacy for in-service teachers to use as a language to talk about their pedagogical work and hence a way of reclaiming some of the ground on what constitutes good teaching. In part, this can be attributed to the numerous observations of teachers’ classroom practice that informed the construction of Productive Pedagogies (PPs). That is, many teachers understand these as naming what ‘good’ teachers have always done. In this paper the value of PPs as a metalanguage for developing pre-service teachers’ knowledge and understanding of teaching is examined; whether PPs is a language that is intelligible for pre-service teachers without access to this prior teacher knowledge or whether its elements and dimensions merely constitute an isolated vocabulary. A case study of four pre-service teachers provides the context for this exploration and its empirical data. Drawing on their fieldwork observations of teaching practice, voiced in the language of PPs, the paper argues that PPs language is indeed useful in the development of pre-service teachers’ understanding of teaching, particularly in assisting them to name evidence of teachers’ recognition of and engagement with difference.

Discriminating ethics

This article examines ethics in work organization and in academic, particularly Critical Management Studies, research. It is centred on empirical data exploring the actions of three employees of a higher education institution who variously failed to resist and/or colluded in the sex discrimination of a colleague.We bring ethics to bear in our analysis of these data in three ways. First, reflecting upon our own methodology, we highlight the difficulties of balancing competing ethical responsibilities when engaging in critical research in contexts defined by adversarial relationships. Second, we highlight how research subjects, who we interpret as exercising problematic agency, draw upon discourses of care, friendship and responsibility to discursively construct their behaviour as moral. Third, drawing upon feminist theory, we reflect upon the ethical warrant of academic critiques of research subjects’ agency. Our analysis raises unsettling implications both for the ethics of Critical Management Studies research and for the function of ethics in organizations.We end by being as concerned by the capacity of ethical discourse to enable and legitimize discrimination as we are reassured by its utility to enable us to discriminate right from wrong behaviour in organizations.

Identifying the extent, motivations and barriers to outsourcing of accounting services

In this paper we analyse the oursourcing of accounting services. The extent to which firms are currently outsourcing, or considering outsourcing such services, and the motivations and barriers associated with outsourcing are identified. Empirical data from a random sample of accounting firms are used in this analysis. Data indicate that the majority of accounting firms are either currently outsourcing or considering outsourcing and that they exopect the volume of oursourced services to increase. In contrast to the scholarly literature advocating labor arbitrage as the primary driver for organizations choosing to outsource, in this study it was found that the main factors underpinning the decision to outsource were the expediting of service delivary to clients, and to enable the firm to focus on its core competencies.

Researching Moslem-Christian marriages : extrapolating from mixed-faith couples towards the practices of Convivencia

Moslem–Christian marriage can be seen as a kind of ‘testing place’ for examining and appreciating the practices of difference. This article offers a summary from a recent local research project which investigated these relationships (Ata, 2003). The empirical data from the study was ‘milled’ for its potential to inform practice, a process that generated four themes that practitioners may find useful in their attempts to design practice approaches that are sensitive to alternative anthropologies. Beginning from the contention that the otherness of those for whom we work can be a mirror for our own cultural and practice assumptions, we extrapolate from these themes to practise with other examples of diversity. It is argued that our efforts to practise with diverse populations will be unengaging, even colonising, unless we are able to denaturalise our own positions.

Comparison theory in economic psychology regarding the easterlin paradox and decreasing marginal utility : a critique

This paper challenges the assumption within Economics that the relationship between money and subjective wellbeing is determined by processes of cognitive comparison. An alternative explanation for such well known phenomena as the Easterlin Paradox and Decreasing Marginal Utility are provided through a consideration of affect. The theoretical basis for such explanations relies on theory from Psychology usually overlooked by Economists, such as affect heuristics and Subjective Wellbeing Homeostasis. The presented evidence for this alternative source of explanation melds psychological theory with empirical data. It is concluded that affective processes offer a coherent alternative explanation for the phenomena under discussion.

Consideration of selflessness and self-interest in outsourcing decisions

Purpose – The paper aims to discuss the need to balance selflessness and self-interest issues in outsourcing decisions. This discussion is timely given the tensions that currently exist between those who want off-shore outsourcing to continue as a means for increasing international trade, and those who only want to conduct business on-shore.

Design/methodology/approach – A conceptual approach has been taken in this paper in order to highlight key considerations for ethical decision-making with respect to off-shore outsourcing.

Findings – Considerations of selflessness and self-interest are embedded in outsourcing decisions. It is recommended that a balance between making profits and fulfilling social responsibilities is required, ideally, at each stage of decision-making. Hence, managers should think critically about the reasons behind off-shore outsourcing decisions, the process of arriving at decisions, and the impact of their decisions on stakeholders.

Research limitations/implications – This is a conceptual paper and further empirical data to validate the stages of decision-making framework are required.

Practical implications – Failure to take into account the selflessness and self-interest outcomes of off-shore outsourcing could potentially off-set strategic gains by leading to negative media publicity for a company.

Social implications – Ethical considerations as part of outsourcing decisions should result in a transparent, fair and more humane working environment for both the host and the home country representatives involved in the process.

Originality/value – This paper presents an original framework of selflessness and self-interest considerations when making off-shore outsourcing decisions. Both Eastern and Western business perspectives have been incorporated as part of the decision-making framework.

Examining the aesthetic dimensions of teaching : relationships between teacher knowledge, identity and passion

Having an appreciation for the subject, their students and what the subject can offer their students has both cognitive and emotional dimensions for teachers. This paper uses empirical data to explore the efficacy of a Deweyan inspired framework called “Aesthetic Understanding” to scrutinise relationships between teacher knowledge, identity and passion. The paper uses case study data of three teachers of maths and/or science generated from a video study to illustrate the relationships between the three elements of Aesthetic Understanding. The need to value the aesthetic dimensions of teaching when examining the subject-specific nature of secondary teaching is discussed.

The capacity of criminal sanctions to shape the behaviour of offenders : specific deterrence doesn’t work, rehabilitation might and the implications for sentencing

There is a considerable gap between the law and knowledge regarding the efficacy of state-imposed sanctions to achieve several key sentencing objectives. Two sentencing objectives which often carry considerable weight in the sentencing calculus are rehabilitation and specific deterrence, despite the fact that neither has been proven to be attainable. This article examines the empirical data on whether specific deterrence and rehabilitation are attainable, and consequently whether they should be retained or abolished as sentencing objectives.

Creating high challenge/high support academic environments through constructive alignment: student outcomes

Higher education needs to provide challenging yet supportive learning environments catering for students with diverse academic needs. There is also an emphasis on using student-driven outcome measures to determine teaching effectiveness. How can these measures be used to reflect upon and evaluate teaching initiatives? Using an undergraduate occupational therapy programme as the site for exploration, this article reports on an application of constructive alignment principles and describes how available empirical data were used to explore student outcomes. A comparison was made between student evaluations and academic grades prior to, and after the implementation of the initiative. Results provide evidence of improvement in student satisfaction and academic grades as a result of implementing constructive alignment. Whilst it is acknowledged that changes in academic grades and student evaluations can be attributed to a number of factors, findings of this study support a view that constructive alignment facilitates students' learning and experiences.

The effect of mathematical games on on-task behaviours in the primary classroom

A challenge for primary classroom teachers is to maintain students’ engagement with learning tasks while catering for their diverse needs, capabilities and interests. Multiple pedagogical approaches are employed to promote on-task behaviours in the mathematics classroom. There is a general assumption by educators that games ignite children’s on-task behaviours, but there is little systemically researched empirical data to support this claim. This paper compares students’ on-task behaviours during non-digital game-playing lessons compared with non-game-playing lessons. Six randomly selected grade 5 and 6 students (9–12 year olds) were observed during ten mathematics lessons. A total of 2,100 observations were recorded via an observational schedule and analysed by comparing the percentage of exhibited behaviours. The study found the children spent 93 % of the class-time exhibiting on-task engagement during the game-playing lessons compared with 72 % during the non-game-playing lessons. The game-playing lessons also promoted greater incidents of student talk related to the mathematical task (34 %) compared with the non-game playing lessons (11 %). These results support the argument that games serve to increase students’ time-on-task in mathematics lessons. Therefore, it is contended that use of games explicitly addressing the mathematical content being taught in a classroom is one way to increase engagement and, in turn, potential for learning.

Modeling of a stereo vision system using a genetic algorithm based fuzzy linear regression

In this paper a fuzzy linear regression (FLR) model integrated with a genetic algorithm (GA) is proposed. The proposed GA-FLR model is applied to modeling of a stereo vision system. A set of empirical data from stereo vision object measurement is collected based on the full factorial design technique. Three regression models, namely ordinary least-squares regression (OLS), FLR, and GA-FLR, are developed, and with their performances compared. The results show that the proposed GA-FLR model performs better than OLS and FLR in modeling of a stereo vision system.