Rats on the run: removal of alien terrestrial predators affects bush rat behaviour

Predators can strongly influence the microhabitat use and foraging behaviour of prey. In a large-scale replicated field experiment in East Gippsland, Australia, we tested the effects of reduced alien red fox (Vulpes vulpes) and alien wild dog (Canis lupus familiaris) abundance (treatment) on native bush rat (Rattus fuscipes) behaviour. Bush rats are exposed to two main guilds of predators, namely mammalian carnivores and birds of prey. Tracking rat movements using the spool-and-line technique revealed that, in treatment sites, rats used ground cover, which provides shelter from predators, less often than at unmanipulated fox and wild dog abundance (non-treatment sites). In treatment sites, rats more frequently moved on logs where they would have been exposed to hunting foxes and dogs than in non-treatment sites. Furthermore, in treatments, rats showed a preference for understorey but not in non-treatments. Hence, bush rats adapted their behaviour to removal of alien terrestrial predators. Giving-up densities (GUDs) indicated no treatment effects on the marginal feeding rate of bush rats. Interestingly, GUDs were higher in open patches than in sheltered patches, suggesting higher perceived predation risk of bush rats during foraging at low versus high cover. The lack of treatment effects on GUDs but the clear response of bush rats to cover may be explained by the impact of predators other than foxes and wild dogs.     

Organophosphorus flame retardants and plasticizers in the atmosphere of the North Sea

Air samples collected in the German part of the North Sea from March to July 2010 were investigated for organophosphorus compounds (OPs) being applied as flame retardants and plasticizers. The ∑₈OPs concentration ranged from 110 to 1400 pg m⁻³ while tris(2-chloroisopropyl) phosphate (TCPP) dominated all samples with individual concentrations up to 1200 pg m⁻³. The highest concentrations were observed in continental air masses showing the high influence of industrialized regions including production sites on atmospheric emissions and concentrations. The occurrence of OPs even in oceanic/Arctic air masses shows that OPs can undergo long-range atmospheric transport. Dry particle-bound deposition fluxes from 9 to 240 ng m⁻² d⁻¹ for ∑₈OPs were estimated leading to a minimum annual flux of 710 ± 580 kg y⁻¹ OPs into the German North Sea. This study presents the first occurrence of OPs in the marine atmosphere together with important information on their long-range transport potential.     

Development of a Specific Anti-capsid Antibody- and Magnetic Bead-Based Immunoassay to Detect Human Norovirus Particles in Stool Samples and Spiked Mussels via Flow Cytometry

Food and Environmental Virology - Human noroviruses impose a considerable health burden globally. Here, a flow cytometry approach designed for their detection in biological waste and food samples...     

Assessing the long-term supply risks for mineral raw materials—a combined evaluation of past and future trends

This paper develops a method for identifying and assessing long-term supply risks for mineral raw materials. The method is based on a combined evaluation of past and future supply and demand trends. By analysing raw material boom and bust cycles over the past 50 years, we have quantified indicators and defined benchmarks for identifying critical market situations. By applying the method, risks for supply shortage may be identified at an early stage. In addition, a numerical evaluation model has been developed for better comparison between various mineral raw materials. Compared to other assessment methods this method uses specific benchmarks for each raw material to better assess supply risks. The method is embedded within a systematic and comprehensive analytical approach.     

Wax perception in honeybees: contact is not necessary

In social insects, much progress has been made in identifying variations in the cuticular signatures of sexes, castes, kin and reproductive status. In contrast to this, we still do not know how the receivers perceive these recognition cues. This study was designed to investigate whether honeybees use contact-chemosensory or olfactory sensilla to perceive wax components. To answer this question in a behavioral assay, we combined classical conditioning of the proboscis extension reaction and a recently established method using zinc sulfate to selectively block antennal contact-chemosensory sensilla. Comparison of the responses to sucrose, wax and geraniol before and after antennal zinc sulfate treatment revealed that the sucrose response is lost after treatment but the responses to wax and geraniol are maintained. As sucrose is perceived by the contact-chemosensory sensilla, the retention of the wax response indicates that contact-chemosensory sensilla are not necessary for wax perception.     

Optimisation of a PMAxx™-RT-qPCR Assay and the Preceding Extraction Method to Selectively Detect Infectious Murine Norovirus Particles in Mussels

Human noroviruses are a major cause for gastroenteritis outbreaks. Filter-feeding bivalve molluscs, which accumulate noroviruses in their digestive tissues, are a typical vector for human infection. RT-qPCR, the established method for human norovirus detection in food, does not allow discrimination between infectious and non-infectious viruses and can overestimate potentially infectious viral loads. To develop a more accurate method of infectious norovirus load estimation, we combined intercalating agent propidium monoazide (PMAxx™)-pre-treatment with RT-qPCR assay using in vitro-cultivable murine norovirus. Three primer sets targeting different genome regions and diverse amplicon sizes were used to compare one-step amplification of a short genome fragment to three two-step long-range RT-qPCRs (7 kbp, 3.6 kbp and 2.3 kbp amplicons). Following initial assays performed on untreated infectious, heat-, or ultraviolet-inactivated murine noroviruses in PBS suspension, PMAxx™ RT-qPCRs were implemented to detect murine noroviruses subsequent to their extraction from mussel digestive tissues; virus extraction via anionic polymer-coated magnetic beads was compared with the proteinase K-dependent ISO norm. The long-range RT-qPCR process detecting fragments of more than 2.3 kbp allowed accurate estimation of the infectivity of UV-damaged murine noroviruses. While proteinase K extraction limited later estimation of PMAxx™ pre-treatment effects and was found to be unsuited to the assay, magnetic bead-captured murine noroviruses retained their infectivity. Genome copies of heat-inactivated murine noroviruses differed by 2.3 log₁₀ between RT-qPCR and PMAxx™-RT-qPCR analysis in bivalve molluscs, the PMAxx™ pre-treatment allowing a closer approximation of infectious titres. The combination of bead-based virus extraction and PMAxx™ RT-qPCR thus provides a more accurate model for the estimation of noroviral bivalve mollusc contamination than the conjunction of proteinase K extraction and RT-qPCR and has the potential (once validated utilising infectious human norovirus) to provide an added measure of security to food safety authorities in the hazard assessment of potential bivalve mollusc contamination.

     

Domestic UNFCCC Kyoto Protocol Mechanisms Project Supply Coordination Through Tendering – Lessons from the New Zealand Experience

A United Nations Framework Convention on Climate Change (UNFCCC) Joint Implementation (JI) host country has to make sure that JI projects are additional to avoid extra costs to generate the reductions necessary to cover the deduction of Emission Reduction Units (ERUs) from the country’s Kyoto Protocol emissions budget. A tender of ERUs by the government allows to generate additional reductions beyond the ERUs issued if it thoroughly checks project additionality. The government of New Zealand is running a tender for JI projects under the title “Projects to Reduce Emissions” since 2003. In two rounds, 10 million ERUs have been awarded and several projects have already entered into contracts with European buyers. The ratio of ERUs awarded to reductions achieved was 0.8 in the second tender. However it remains to be seen whether the additionality test of this tender is sufficient to exclude clearly non-additional projects.