Resource subsidies to opportunistic predators may alter natural predator–prey relationships and, in turn, have implications for how these predators affect co-occurring prey. To explore this idea, we ...compared the prey available to and eaten by a top canid predator, the Australian dingo (Canis lupus dingo), in areas with and without human-provided food. Overall, small mammals formed the majority of dingo prey, followed by reptiles and then invertebrates. Where human-provided food resources were available, dingoes ate them; 17 % of their diet comprised kitchen waste from a refuse facility. There was evidence of dietary preference for small mammals in areas where human-provided food was available. In more distant areas, by contrast, reptiles were the primary prey. The level of seasonal switching between small mammals and reptiles was also more pronounced in areas away from human-provided food. This reaffirmed concepts of prey switching but within a short, seasonal time frame. It also confirmed that the diet of dingoes is altered where human-provided food is available. We suggest that the availability of anthropogenic food to this species and other apex predators therefore has the potential to alter trophic cascades.
Hybridization between domesticated animals and their wild counterparts can disrupt adaptive gene combinations, reduce genetic diversity, extinguish wild populations and change ecosystem function. The ...dingo is a free‐ranging dog that is an iconic apex predator and distributed throughout most of mainland Australia. Dingoes readily hybridize with domestic dogs, and in many Australian jurisdictions, distinct management strategies are dictated by hybrid status. Yet, the magnitude and spatial extent of domestic dog–dingo hybridization is poorly characterized. To address this, we performed a continent‐wide analysis of hybridization throughout Australia based on 24 locus microsatellite DNA genotypes from 3637 free‐ranging dogs. Although 46% of all free‐ranging dogs were classified as pure dingoes, all regions exhibited some hybridization, and the magnitude varied substantially. The southeast of Australia was highly admixed, with 99% of animals being hybrids or feral domestic dogs, whereas only 13% of the animals from remote central Australia were hybrids. Almost all free‐ranging dogs had some dingo ancestry, indicating that domestic dogs could have poor survivorship in nonurban Australian environments. Overall, wild pure dingoes remain the dominant predator over most of Australia, but the speed and extent to which hybridization has occurred in the approximately 220 years since the first introduction of domestic dogs indicate that the process may soon threaten the persistence of pure dingoes.
In an age when large corporations dominate the economic and political landscape, it is tempting to think that their power goes largely unchecked. Originally published in 2007, Contesting the ...Corporation counters this view by showing that today's corporations are driven by political struggle, power plays and attempts to resist control. Building on a wide range of theoretical sources, Fleming and Spicer present an analysis of the different ways in which power operates within the modern workplace. They begin by building a theoretical perspective that synthesizes previous investigations of power and resistance, identifying struggle as a key concept. Each chapter illustrates a different dimension of workplace struggle through an array of original empirical studies relating to sexuality, cynicism, new social movements and new-wave trade unionism. The book concludes by demonstrating that social justice claims underlie even the most innocuous forms of resistance, helping to transform some of the largest modern corporations.
The risk of sudden infant death syndrome (SIDS) among infants who co-sleep in the absence of hazardous circumstances is unclear and needs to be quantified.
Combined individual-analysis of two ...population-based case-control studies of SIDS infants and controls comparable for age and time of last sleep.
Parents of 400 SIDS infants and 1386 controls provided information from five English health regions between 1993-6 (population: 17.7 million) and one of these regions between 2003-6 (population:4.9 million).
Over a third of SIDS infants (36%) were found co-sleeping with an adult at the time of death compared to 15% of control infants after the reference sleep (multivariate OR = 3.9 95% CI: 2.7-5.6). The multivariable risk associated with co-sleeping on a sofa (OR = 18.3 95% CI: 7.1-47.4) or next to a parent who drank more than two units of alcohol (OR = 18.3 95% CI: 7.7-43.5) was very high and significant for infants of all ages. The risk associated with co-sleeping next to someone who smoked was significant for infants under 3 months old (OR = 8.9 95% CI: 5.3-15.1) but not for older infants (OR = 1.4 95% CI: 0.7-2.8). The multivariable risk associated with bed-sharing in the absence of these hazards was not significant overall (OR = 1.1 95% CI: 0.6-2.0), for infants less than 3 months old (OR = 1.6 95% CI: 0.96-2.7), and was in the direction of protection for older infants (OR = 0.1 95% CI: 0.01-0.5). Dummy use was associated with a lower risk of SIDS only among co-sleepers and prone sleeping was a higher risk only among infants sleeping alone.
These findings support a public health strategy that underlines specific hazardous co-sleeping environments parents should avoid. Sofa-sharing is not a safe alternative to bed-sharing and bed-sharing should be avoided if parents consume alcohol, smoke or take drugs or if the infant is pre-term.
Rabbit Haemorrhagic Disease Virus (RHDV), which is a calicivirus, is used as a biocontrol agent to suppress European wild rabbit populations in Australia. The transmission of RHDV can be influenced ...by social interactions of rabbits; however, there is a paucity of this knowledge about juvenile rabbits and the roles they may play in the transmission of RHDV. We aimed to quantify the social interactions of juvenile (< 900 g) and adult (> 1200 g) rabbits in a locally abundant population in the Central Tablelands of New South Wales, Australia. Twenty-six juvenile and 16 adult rabbits were fitted with VHF proximity loggers to monitor intra- and inter-group pairings. Use of multiple warrens by these rabbits was investigated using VHF base stations at nine warrens and on foot with a hand-held Yagi antenna. Juvenile rabbits were strongly interconnected with both juveniles and adults within and outside their warren of capture, and almost all juveniles were well-connected to other individuals within their own social group. Inter-group pairings were infrequent and fleeting between adults. Both juvenile and adult rabbits used multiple warrens. However, visits to warrens outside their warren of capture, particularly those within 50 m, were more common and longer in duration in juveniles than in adults. The high connectivity of juveniles within and between warrens in close proximity increases potential pathogen exchange between warrens. Therefore, juvenile rabbits could be of greater importance in lagovirus transmission than adult rabbits. The strength of juvenile rabbit inter- and intra-group pairings, and their tendency to use multiple warrens, highlight their potential to act as ‘superspreaders’ of both infection and immunity for lagoviruses and other pathogens with similar lifecycles. Confirmation of this potential is required through examination of disease progress and rabbit age-related immune responses during outbreaks.
The simultaneous optimization of many objectives (in excess of 3), in order to obtain a full and satisfactory set of tradeoff solutions to support a posteriori decision making, remains a challenging ...problem. The concept of coevolving a family of decision-maker preferences together with a population of candidate solutions is studied here and demonstrated to have promising performance characteristics for such problems. After introducing the concept of the preference-inspired coevolutionary algorithm (PICEA), a realization of this concept, PICEA-g, is systematically compared with four of the best-in-class evolutionary algorithms (EAs); random search is also studied as a baseline approach. The four EAs used in the comparison are a Pareto-dominance relation-based algorithm (NSGA-II), an ε-dominance relation-based algorithm ε-multiobjective evolutionary algorithm (MOEA), a scalarizing function-based algorithm (MOEA/D), and an indicator-based algorithm hypervolume-based algorithm (HypE). It is demonstrated that, for bi-objective problems, all of the multi-objective evolutionary algorithms perform competitively. As the number of objectives increases, PICEA-g and HypE, which have comparable performance, tend to outperform NSGA-II, ε-MOEA, and MOEA/D. All the algorithms outperformed random search.
Camera traps are electrical instruments that emit sounds and light. In recent decades they have become a tool of choice in wildlife research and monitoring. The variability between camera trap models ...and the methods used are considerable, and little is known about how animals respond to camera trap emissions. It has been reported that some animals show a response to camera traps, and in research this is often undesirable so it is important to understand why the animals are disturbed. We conducted laboratory based investigations to test the audio and infrared optical outputs of 12 camera trap models. Camera traps were measured for audio outputs in an anechoic chamber; we also measured ultrasonic (n = 5) and infrared illumination outputs (n = 7) of a subset of the camera trap models. We then compared the perceptive hearing range (n = 21) and assessed the vision ranges (n = 3) of mammals species (where data existed) to determine if animals can see and hear camera traps. We report that camera traps produce sounds that are well within the perceptive range of most mammals' hearing and produce illumination that can be seen by many species.
Generation expansion planning consists of finding the optimal long-term plan for the construction of new generation capacity subject to various economic and technical constraints. It usually involves ...solving a large-scale, non-linear discrete and dynamic optimisation problem in a highly constrained and uncertain environment. Traditional approaches to capacity planning have focused on achieving a least-cost plan. During the last two decades however, new paradigms for expansion planning have emerged that are driven by environmental and political factors. This has resulted in the formulation of multi-criteria approaches that enable power system planners to simultaneously consider multiple and conflicting objectives in the decision-making process. More recently, the increasing integration of intermittent renewable energy sources in the grid to sustain power system decarbonisation and energy security has introduced new challenges. Such a transition spawns new dynamics pertaining to the variability and uncertainty of these generation resources in determining the best mix. In addition to ensuring adequacy of generation capacity, it is essential to consider the operational characteristics of the generation sources in the planning process. In this paper, we first review the evolution of generation expansion planning techniques in the face of more stringent environmental policies and growing uncertainty. More importantly, we highlight the emerging challenges presented by the intermittent nature of some renewable energy sources. In particular, we discuss the power supply adequacy and operational flexibility issues introduced by variable renewable sources as well as the attempts made to address them. Finally, we identify important future research directions.
Dogs (Canis familiaris) can transmit pathogens to other domestic animals, humans and wildlife. Both domestic and wild-living dogs are ubiquitous within mainland Australian landscapes, but their ...interactions are mostly unquantified. Consequently, the probability of pathogen transfer among wild-living and domestic dogs is unknown. To address this knowledge deficit, we established 65 camera trap stations, deployed for 26,151 camera trap nights, to quantify domestic and wild-living dog activity during 2 years across eight sites in north-east New South Wales, Australia. Wild-living dogs were detected on camera traps at all sites, and domestic dogs recorded at all but one. No contacts between domestic and wild-living dogs were recorded, and limited temporal overlap in activity was observed (32 %); domestic dogs were predominantly active during the day and wild-living dogs mainly during the night. Contact rates between wild-living and between domestic dogs, respectively, varied between sites and over time (range 0.003–0.56 contacts per camera trap night). Contact among wild-living dogs occurred mainly within social groupings, and peaked when young were present. However, pup emergence occurred throughout the year within and between sites and consequently, no overall annual cycle in contact rates could be established. Due to infrequent interactions between domestic and wild-living dogs, there are likely limited opportunities for pathogen transmission that require direct contact. In contrast, extensive spatial overlap of wild and domestic dogs could facilitate the spread of pathogens that do not require direct contact, some of which may be important zoonoses.
Free-roaming dogs (Canis familiaris) are common worldwide, often maintaining diseases of domestic pets and wildlife. Management of these dogs is difficult and often involves capture, treatment, ...neutering and release. Information on the effects of sex and reproductive state on intraspecific contacts and disease transmission is currently lacking, but is vital to improving strategic management of their populations. We assessed the effects of sex and reproductive state on short-term activity patterns and contact rates of free-roaming dogs living in an Australian Indigenous community. Population, social group sizes and rates of contact were estimated from structured observations along walked transects. Simultaneously, GPS telemetry collars were used to track dogs' movements and to quantify the frequency of contacts between individual animals. We estimated that the community's dog population was 326 ± 52, with only 9.8 ± 2.5% confined to a house yard. Short-term activity ranges of dogs varied from 9.2 to 133.7 ha, with males ranging over significantly larger areas than females. Contacts between two or more dogs occurred frequently, with entire females and neutered males accumulating significantly more contacts than spayed females or entire males. This indicates that sex and reproductive status are potentially important to epidemiology, but the effect of these differential contact rates on disease transmission requires further investigation. The observed combination of unrestrained dogs and high contact rates suggest that contagious disease would likely spread rapidly through the population. Pro-active management of dog populations and targeted education programs could help reduce the risks associated with disease spread.
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