Intra-sexual variability in feeding behaviour of a mountain ungulate: size matters

Many studies comparing the behaviour of individuals of different genders or species showed that animal body mass and forage quality/quantity are key elements of the foraging ecology of herbivores. Since body mass could also influence the animal’s sensitivity to predation risk, its vigilance behaviour should consequently be affected. Alpine ibex (Capra ibex) is characterised by a strong dimorphism among males of different ages, thus representing an ideal case study for testing the Jarman-Bell principle, avoiding possibly misleading effects resulting from the comparison between different species or genders. We analysed the fine-scale foraging behaviour of male ibex in order to assess the effect of body mass and the effects of vegetation quality/quantity on both foraging and vigilance behaviour. Our results showed that smaller males were more selective than larger ones, on account of their lower capability of digesting plant. Smaller males scanned the environment more frequently than larger ones. Male ibex grazed more selectively in sites with high quality forage and their bite rate increased as forage biomass decreased. Vigilance frequency increased with increasing forage biomass as, under these circumstances, ibex are able to prolong anti-predator vigilance while chewing bites that have already been cropped. Our findings highlight the effects of body mass per se on both foraging and anti-predator behaviours in herbivores, thus supporting the Jarman-Bell principle. Foraging can arguably be considered a very flexible behaviour with high evolutionary relevance as it enables herbivores to optimally adjust their total energy intake under varying conditions of food resources.     

Mediating male–male interactions: the role of the UV blue crest coloration in blue tits

Badges of status, usually color patches, are hypothesized to serve as important signals within natural populations by communicating an individual’s fighting ability or aggressiveness before an interaction ever takes place. These signals, which may evolve via sexual and/or social selection, mediate intra-specific competition by influencing the outcome or escalation of contests between individuals. The last 10 years saw the rise of interest in the role of ultraviolet (UV)-based coloration in intra-sexual communication. However, the rare experimental studies that tested this hypothesis found opposite results, which may originate from the different methodological procedures used to assess the badge of status theory. We present here the results of an experiment testing whether male blue tits (Cyanistes caeruleus) respond differently to unfamiliar conspecifics presenting contrasted UV crest coloration. In an aviary, we simultaneously presented two caged blue tits with enhanced (UV+) or reduced (UV−) crest coloration to a focal bird. We found that focal males acted more aggressively towards the UV− males than UV+ males. In addition, focal males fed more often close to males that were similar in brightness or duller than themselves. We conclude that, in blue tits, UV blue crest coloration affects both social and aggressive responses towards unfamiliar individuals, and thus it has some properties of a badge of status.     

Closing the Incentive Gap: The Role of Public and Private Actors in Governing Indonesia's Tuna Fisheries

Indonesia is one of the world's largest tuna producing countries, yet regulatory oversight remains weak and management is poor. Incentive-based approaches are a way to improve state-based resource management, but they often require strong government regulation. In this paper, we use principal–agent theory and the notion of the ‘incentive gap’ to explore how incentives could be brought to bear in Indonesia through a combination of private and public actors. With a shared fish stock like tuna, we argue that a double principal–agent problem emerges, where information, asymmetries between various players complicate management. We focus on the problems of adverse selection and moral hazard in three different tuna fisheries in Indonesia to identify the nature of the incentive gap, and comment on the mix of public and private actors currently engaged in tuna fishery governance towards reducing the gap. The double principal–agent problem is a useful yet underutilized framework to understand the dynamics of shared stocks management. In this first application to a developing country fishery, we conclude that information asymmetries cannot be overcome without the involvement of private actors, who are increasingly becoming important in aligning regional and global objectives with those of fishers themselves.     

Understanding climate,adapting to change: indigenous cultural values and climate change impacts in North Queensland

Many authors have suggested that Indigenous communities are especially vulnerable to the direct and indirect impacts of climate change, yet there remains a paucity of fine-grained geographic data on the particular impacts of climate change on specific places and on local communities, especially Australian Indigenous communities. While there are some recent studies being undertaken with Australia's Torres Strait Island people, our research takes up the issues of vulnerability and resilience with two Indigenous communities from different environments on the mainland in North Queensland. They are the Aboriginal peoples of the rainforest and reef environments of the Wet Tropics and the Aboriginal people of the discontiguous rainforest, grasslands, dry forests and marine environments of Cape York. The results demonstrate variability in their understandings of climate change and in their capacities to anticipate and manage its impacts, while at the same time illustrating some common held themes about environmental and cultural values, observed environmental change, attributions of cause and effect, and of climate in general.     

Mothers living with contamination of perfluoroalkyl substances: an assessment of the perceived health risk and self-reported diseases

Environmental Science and Pollution Research - Widespread contamination of the superficial, drinking, and groundwater by perfluoroalkyl substances (PFASs) was discovered in the Veneto Region...     

Biodegradation of LDPE/Modified Starch Blends Sterilized with Gamma Radiation

Blends of LDPE/modified starch were prepared, sterilized by gamma radiation and investigated with respect to their microbial degradation by a mixture of fungal strains in liquid medium after 90 days, was analyzed by carbon dioxide (CO₂) production (Sturm test). Biodegradation of blends was evaluated by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction; mechanical testing, scanning electron microscopy (SEM). The biodegradation of LDPE/modified starch blends was attributed to microbiological attack, with alterations in the chemical structure of the blend with an increase in the carbonyl and vinyl indices and the appearance of new crystalline symmetry generating a crystalline domain not existing before in the blend and decrease in the mechanical properties.     

Trust and distrust in safety leadership: Mirror reflections?

Although research shows that employees’ trust and distrust in management influences their safety behavior, less is known about how these attitudes develop. Based on two-factor models of trust, we hypothesize that distinct trustworthiness qualities precede the development of employees’ trust and distrust in their supervisors. Eighty-five UK construction employees responded to a paired comparison test of trustworthiness qualities, which provided 56 and 53 consistent rankings for trust and distrust, respectively. Consistent with our hypotheses, integrity (measured through honesty) was found to be the most important attitude in the development of both trust and distrust, while a reversed ordering of importance emerged for ability (measured through competence) and benevolence (measured through concern) in the development of trust and distrust. In all cases, only a small number of qualities were most important in the development of each attitude. We discuss how safety initiatives that focus on trust might gain by addressing the qualities that we identify.