1,067 research outputs found
Pathogen dose infectivity curves as a method to analyze the distribution of host susceptibility : a quantitative assessment of maternal effects after food stress and pathogen exposure
Shooting our wildlife: an analysis of the law and policy governing the killing of kangaroos
Although we kill around 3 million kangaroos annually, the current widespread commercial and non-commercial killing of kangaroos has yet to be proven necessary according to this report.
Over the last decade in Australia, the Federal and State governments have approved an annual commercial kill of some four to six million kangaroos and wallabies each year. On average three million kangaroos are actually ‘harvested’/killed.2 Around three hundred thousand young at foot and 800,000 pouch young are either killed or left to die each year as collateral of the commercial industry. In addition, up to 200,000 kangaroos and wallabies are killed for non-commercial reasons each year. A further unknown number are killed without government authorisation. This is the largest land-based slaughter of wildlife in the world.
This report provides an analysis of the law and policy governing the killing of kangaroos. It provides an historical outline of kangaroo killing in Australia and examines the reasons for and against the kill. The report describes and analyses the legislative and regulatory framework governing the killing of kangaroos, in order to assist policymakers understand an area which is complex and often misunderstood.
The conclusion of this report is that the current widespread commercial and non-commercial killing of kangaroos has yet to be proven necessary. Governments do not provide any clear justification for the killing such as through a proper consideration of the reasons for and against control. State governments once treated kangaroos as agricultural pests yet today they are treated as a resource. These practices result in poor welfare outcomes for many kangaroos and joeys and may pose a risk to Australia’s sustainability
The role of inspections in the commercial kangaroo industry
This article provides an assessment of the enforcement of the law governing commercial kangaroo killing, focusing particularly upon inspectorial practices. Australias kangaroo industry is the largest commercial kill of land-based wildlife in the world. Professional shooters hunt kangaroos in rural and remote locations at night. Due to the remote and decentralised nature of the killing, the industry presents unique challenges to law enforcement agencies that are responsible for the enforcement of animal welfare standards. This article focuses upon the role that inspections have in detecting offences within the commercial kangaroo industry. It provides a comparative analysis across the states, highlighting key differences in terms of inspectorial practices and the resulting outcomes. A common theme across all of the jurisdictions is that none of the agencies responsible for enforcement regularly conduct inspections of shooters, making it impossible to ensure that these parties are complying with the National Code of Practice for the Humane Shooting of Kangaroos and Wallabies. Recommendations for reform are offered, including stronger compliance policy, higher rates of inspection, increased resourcing and the introduction of alternative methods of inspection
'Pest' and resource: A legal history of Australia's kangaroos
This paper presents an investigation into the legal history of Australias kangaroos. It aims to provide a detailed analysis of how the law and policy governing the killing of kangaroos has evolved over time in response to changing public perceptions. This history begins with the pre-European period and traces the impact of European colonisation, early growth of the commercial kangaroo industry, and the increased role of science and regulation upon kangaroos. The paper critiques the historical designation of kangaroos as `pests that need to be `managed and argues that such an approach is inconsistent with current scientific understanding. As this `pest status has fallen in importance there has been a shift in regulatory goals from damage mitigation to resource utilisation, although government planning and policy continue to cite damage mitigation alongside objectives to maintain viable populations and a sustainable and commercially viable industry. While the kangaroo industrys current focus is upon the `sustainable use of wildlife, the history of attitudes towards kangaroos as `pests is so deeply and widely entrenched that it is impossible for the industry to meet welfare standards. The article concludes that the commercial kangaroo industry does not have any clearly defined policy benefit and should be reassessed to take greater account of the impact it has on ecosystems and kangaroo welfar
Genetic Drift Shapes the Evolution of a Highly Dynamic Metapopulation
The dynamics of extinction and (re)colonization in habitat patches are characterizing features of dynamic metapopulations, causing them to evolve differently than large, stable populations. The propagule model, which assumes genetic bottlenecks during colonization, posits that newly founded subpopulations have low genetic diversity and are genetically highly differentiated from each other. Immigration may then increase diversity and decrease differentiation between subpopulations. Thus, older and/or less isolated subpopulations are expected to have higher genetic diversity and less genetic differentiation. We tested this theory using whole-genome pool-sequencing to characterize nucleotide diversity and differentiation in 60 subpopulations of a natural metapopulation of the cyclical parthenogen Daphnia magna. For comparison, we characterized diversity in a single, large, and stable D. magna population. We found reduced (synonymous) genomic diversity, a proxy for effective population size, weak purifying selection, and low rates of adaptive evolution in the metapopulation compared with the large, stable population. These differences suggest that genetic bottlenecks during colonization reduce effective population sizes, which leads to strong genetic drift and reduced selection efficacy in the metapopulation. Consistent with the propagule model, we found lower diversity and increased differentiation in younger and also in more isolated subpopulations. Our study sheds light on the genomic consequences of extinction-(re)colonization dynamics to an unprecedented degree, giving strong support for the propagule model. We demonstrate that the metapopulation evolves differently from a large, stable population and that evolution is largely driven by genetic drift.Peer reviewe
Homogenisation of nonlinear blood flow in periodic networks: the limit of small haematocrit heterogeneity
In this work we develop a homogenisation methodology to upscale mathematical
descriptions of microcirculatory blood flow from the microscale (where
individual vessels are resolved) to the macroscopic (or tissue) scale. Due to
the assumed two-phase nature of blood and specific features of red blood cells
(RBCs), mathematical models for blood flow in the microcirculation are highly
nonlinear, coupling the flow and RBC concentrations (haematocrit). In contrast
to previous works which accomplished blood-flow homogenisation by assuming that
the haematocrit level remains constant, here we allow for spatial heterogeneity
in the haematocrit concentration and thus begin with a nonlinear microscale
model. We simplify the analysis by considering the limit of small haematocrit
heterogeneity which prevails when variations in haematocrit concentration
between neighbouring vessels are small. Homogenisation results in a system of
coupled, nonlinear partial differential equations describing the flow and
haematocrit transport at the macroscale, in which a nonlinear Darcy-type model
relates the flow and pressure gradient via a haematocrit-dependent permeability
tensor. During the analysis we obtain further that haematocrit transport at the
macroscale is governed by a purely advective equation. Applying the theory to
particular examples of two- and three-dimensional geometries of periodic
networks, we calculate the effective permeability tensor associated with blood
flow in these vascular networks. We demonstrate how the statistical
distribution of vessel lengths and diameters, together with the average
haematocrit level, affect the statistical properties of the macroscopic
permeability tensor. These data can be used to simulate blood flow and
haematocrit transport at the macroscale.Comment: 34 pages, 8 figure
The expression of virulence for a mixed-mode transmitted parasite in a diapausing host
Many parasites survive harsh periods together with their hosts. Without the possibility of horizontal transmission during host diapause, parasite persistence depends entirely on host survival. We therefore hypothesize that a parasite should be avirulent during its host's diapausing stage. In contrast, the parasite may express higher virulence, i.e. parasite-induced fitness reduction of the host, during host life stages with good opportunities for horizontal transmission. Here we study the effects of a vertically and horizontally transmitted microsporidium parasite, Hamiltosporidium tvaerminnensis, on the quantity and survival of resting eggs of its host Daphnia magna. We find that the parasite did not affect egg volume, hatching success and time to hatching of the Daphnia's resting eggs, although it did strongly reduce the number of resting eggs produced by infected females, revealing high virulence during the non-diapause phase of the host's life cycle. These results also explain another aspect of this system - namely the strong decline in natural population prevalence across diapause. This decline is not caused by mortality in infected resting stages, as was previously hypothesized, but because infected female hosts produce lower rates of resting eggs. Together, these results help explain the epidemiological dynamics of a microsporidian disease and highlight the adaptive nature of life stage-dependent parasite virulenc
First impressions and perceived roles: Palestinian perceptions on foreign aid
This paper summarizes some results of a wider research on foreign aid that was conducted in the West Bank and Gaza Strip in 2010. It seeks to describe the impressions and feelings of Palestinian aid beneficiaries as well as the roles and functions they attached to foreign aid. To capture and measure local perceptions on Western assistance a series of individual in depth interviews and few focus group interviews were conducted in the Palestinian territories. The interview transcripts were processed by content analysis. As research results show — from the perspective of aid beneficiaries — foreign aid is more related to human dignity than to any economic development. All this implies that frustration with the ongoing Israeli-Palestinian conflict inevitably embraces the donor policies and practices too
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