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Many cavity nesters add volatile plants with medicinal properties to their nests. In Australia, eucalyptus and tea-trees are highly volatile plants, which have antiparasitic and antimicrobial properties. Here, we tested whether scents of eucalypt (Eucalyptus polybractea) and tea tree (Melaleuca alternifolia) essential oils can attract birds to newly installed nest boxes. Twenty-four nest boxes received three scent treatments (eucalypt, tea tree, control) for 10 days each using a Latin-square design. Bird visitation was recorded using camera traps. Eastern Rosellas (Platycercus eximius) visited the nest boxes the most (1,454 visits) and were therefore the focus of the study. Eastern Rosellas did not change their behaviours in response to the eucalypt scent in nest boxes: there was no difference in visitation, duration of visits or nest box inspection behaviour between nest boxes with eucalypt scent and those with the control scent. However, Eastern Rosellas visited nest boxes with tea tree scent less frequently and spent less time at these boxes than those with the control scent. The mean time that Eastern Rosellas spent inspecting boxes slightly increased over the 10-day period following scent placement at boxes with control and eucalypt scents, while it sharply decreased at boxes with tea tree scent. This is the first study demonstrating that an Australian bird detected and behaved differently in response to plant volatiles. The use of scents may offer opportunities to not only attract, but potentially also deter certain birds from using particular hollows. [ABSTRACT FROM AUTHOR]

Simple Summary: Insects, including dung beetles, rely on volatile cues to locate food and mates. However, the antennal responses of dung beetles to dung headspace volatiles have received minimal attention. To address this gap, we conducted a scanning electron microscopy study to examine the density distribution of three types of antennal sensilla in three introduced dung beetle species found in Australia: Geotrupes spiniger, Bubas bison and Onitis aygulus. The gross morphology of the antennal sensilla of these species is described here for the first time. Notably, we observed distinct patterns of sensilla trichodea, sensilla basiconica and sensilla chaetica on the proximal and distal surfaces of three lamellae in their antennal clubs. Furthermore, using electroantennography, we investigated the olfactory responses of these dung beetles to ten selected dung volatiles and mixtures of the same volatiles. The test chemicals evoked differential antennal responses in all three test species. The results are discussed in relation to the distribution and density of the antennal sensilla and the potential role of dung headspace volatiles in dung preference by these dung beetles. Overall, our findings indicate the possibility of using EAG-active compounds to attract dung beetles in the field. Locating sporadically distributed food resources and mate finding are strongly aided by volatile cues for most insects, including dung beetles. However, there is limited information on the olfactory ecology of dung beetles. We conducted a scanning electron microscopy study on the morphology and distribution of the antennal sensilla of three introduced dung beetle species in Australia: Geotrupes spiniger (Coleoptera: Geotrupidae), Bubas bison and Onitis aygulus (Coleoptera: Scarabaeidae). Three main morphological types of antennal sensilla were identified: sensilla trichodea (ST), sensilla basiconica (SB) and sensilla chaetica (SCh). Distinct variations of SB distribution were observed in B. bison and G. spiniger and on different lamellar surfaces in both sexes of all three species. Sexual dimorphism in antennal sensilla distribution or their abundance was not evident. To complement the morphological characterisation of sensilla, electroantennography (EAG) was carried out to construct EAG response profiles of the three species to selected dung volatiles. An initial study revealed that antennae of all species were sensitive to a mix of phenol, skatole, indole, p-cresol, butanone and butyric acid, common components of livestock dung headspace. In addition to these six compounds, dimethyl sulfide, dimethyl disulfide, eucalyptol and toluene were tested for antennal activity. All compounds evoked measurable EAG responses, confirming antennal sensitivity. Geotrupes spiniger exhibited significant responses to all the compounds compared to the control, whereas B. bison and O. aygulus only responded to a subset of compounds. A comparison of relative EAG amplitudes revealed highly significant responses to p-cresol in G. spiniger and to skatole in B. bison. Geotrupes spiniger displayed differential responses to all the compounds. Pooled EAG data suggest highly significant differences in responses among the three species and among compounds. Our findings suggest that a blend of volatiles may offer potential for the trapping of dung beetles, thereby avoiding the use of dung baits that are inconvenient, inconsistent and may pose a threat to farm biosecurity. [ABSTRACT FROM AUTHOR]

The Queensland fruit fly (Bactrocera tryoni) is a major polyphagous pest widespread in Australia and several Pacific Islands. Bacteria present on the host plant phyllosphere supply proteins, essential for egg development and female sexual maturity. We investigated the role of microbial volatile organic compounds (MVOCs) emitted by Enterobacteriaceae commonly found on the host plant and in the fly gut in attracting virgin females. Bacteria were cultured on artificial media and natural fruits, at various pH, and MVOCs were collected using different headspace volatile absorbent materials. The olfactory responses of virgin females to bacterial MVOCs were assessed via electrophysiology and behavioral assays. The production of MVOCs was strongly influenced qualitatively by the bacterial strain and the type of media, and it semi-quantitatively varied with pH and time. MVOCs emitted by Klebsiella oxytoca invoked the strongest antennal response and were the most attractive. Among the identified compounds triggering an olfactory response, D-limonene and 2-nonanone were both significantly behaviorally attractive, whereas phenol, nonanal, isoamyl alcohol, and some pyrazines appeared to be repulsive. This study deepens our understanding of the chemical ecology between fruit flies and their bacterial symbionts and paves the way for novel synthetic lures based on specifically MVOCs targeting virgin females. [ABSTRACT FROM AUTHOR]

An important but understudied modality for eavesdropping between predators and prey is olfaction, especially between non-mammalian vertebrate predators and their prey. Here we test three olfactory eavesdropping predictions involving an apex reptilian predator, the sand goanna Varanus gouldii, and several species of its small mammalian prey in arid central Australia: 1) small mammals will recognize and avoid the odour of V. gouldii; 2) V. gouldii will be attracted to the odour of small mammals, especially of species that maximize its energetic returns; and 3) small mammals will be less mobile and will show higher burrow fidelity where V. gouldii is absent compared with where it is present. As expected, we found that small mammals recognized and avoided faecal odour of this goanna, feeding less intensively at food patches where the odour of V. gouldii was present than at patches with no odour or a pungency control odour. Varanus gouldii also was attracted to the odour of small mammals in artificial burrows and dug more frequently at burrows containing the odour of species that were energetically profitable than at those of species likely to yield diminishing returns. Our third prediction received mixed support. Rates of movement of three species of small mammals were no different where V. gouldii was present or absent, but burrow fidelity in two of these species increased as expected where V. gouldii had been removed. We conclude that olfaction plays a key role in the dynamic interaction between V. gouldii and its mammalian prey, with the interactants using olfaction to balance their respective costs of foraging and reducing predation risk. We speculate that the risk of predation from this apex reptilian predator drives the highly unusual burrow-shifting behaviour that characterizes many of Australia's small desert mammals. [ABSTRACT FROM AUTHOR]

Invasive mammalian predators have had a devastating effect on native species globally. The European red fox (Vulpes vulpes) is one such species where it has been introduced in Australia. A novel but unexplored tactic to reduce the impact of mammalian predators is the use of unrewarded prey odors to undermine the effectiveness of olfactory hunting behavior. To test the viability of unrewarded prey odors in an applied setting we investigated how foxes responded to the odors of three different prey species. We used the odors of two locally extinct native Australian marsupials; the eastern quoll (a smaller carnivore) and eastern bettong (a fungivore), and the European rabbit, an introduced herbivore. Conducting our research over a period of 3 weeks in a pastoral environment in South‐eastern Australia, we used video observations of foxes' behaviors, as they encountered the different odors. We found a reduction in the number of fox visits to bettong odors in the third week. In contrast, we observed a sustained number of visits to rabbit odors. Foxes also spent more time investigating rabbit odors and displayed longer durations of vigilance behavior at quoll odors. Our results support the hypothesis that the exposure of wild foxes to unrewarded odors of novel prey species can reduce their interest in these odors, which might translate to a reduction in predation pressure. Our results also suggest, however, that olfactory pre‐exposure may not be as effective at reducing fox interest in a competitor species' odor. [ABSTRACT FROM AUTHOR]

As global chemical manufacturing has historically relied on inexpensive feedstocks from the petrochemical industry, the identification of new naturally derived feedstocks represents an important and sustainable alternative. This review introduces Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson as an attractive renewable resource of natural compounds for organic chemical transformations. Although native to Australia, this plant species is now grown and harvested worldwide. The chemical composition of citriodora oils varies with location, harvesting season and age of leaves. Beyond their historic uses as fragrances or repellents, the more abundant terpenes found in citriodora oils such as citronellal, citronellol, and isopulegol have notable roles in the manufacture of fine chemicals. This review highlights several industrial processes intimately related to the citriodora terpenes, some advances in fragrances and repellents, as well as the use of these terpenes in the most recently reported synthesis of bioactive compounds. Where relevant, processes highlighting the adoption of green chemistry principles are presented and briefly discussed. [ABSTRACT FROM AUTHOR]

Females of the Queensland fruit fly (QFF), Bactrocera tryoni, are amongst the most damaging pests of horticulture in Australia and neighboring countries. Females can lay eggs into more than a hundred species of fruits and vegetables, resulting in large crop losses. Sexually mature males can be managed sustainably with traps baited with long-lasting synthetic lures, and sexually immature males and females can be attracted and killed by short-lived protein baits applied directly on surfaces, with a low success rate (< 20%). No long-lasting attractants for virgin or mated females exist. With the aim of developing a female attractant for surveillance, we collected and analyzed the odors of four ripe host fruits: orange, cherry guava, banana and feijoa. Virgin and mated female QFF were tested with gas-chromatography coupled with electro-antennographic detection to identify electrophysiologically (EAD)-active compounds. We detected 41 EAD-active compounds, with seven found common for more than one fruit. Overall, mated females responded more often and with higher intensity than virgin females. In particular, five compounds present either in cherry guava or feijoa triggered a significantly higher EAD response from mated females than from virgins. Twenty-six EAD-active compounds were selected and tested individually in a Y-tube olfactometer to measure attraction of both virgin and mated females. Behavioral responses differed significantly amongst the compounds, but not strongly between virgin and mated females. We did not find any correlation between electrophysiological and behavioral responses. Further field testing with behaviorally-active compounds is needed for the development of a new QFF female lure. [ABSTRACT FROM AUTHOR]

The present study provides a detailed analysis of the factors influencing variation in cyanobacterial communities of a large shallow off-river drinking water reservoir on the east coast of Australia. Receiving multiple inflows from two unprotected mixed land-use catchments, the Grahamstown Reservoir is a model example of a reservoir which is highly vulnerable to adverse water quality issues, including phytoplankton blooms and the resulting filtration, toxin and taste and odour problems produced. The spatial and temporal distributions of cyanobacteria were assessed for a period of 3 years (January 2012–December 2014) based on samples collected from three monitoring stations within the reservoir. Relationships between cyanobacterial abundance and a range of environmental factors were evaluated by application of multivariate curve resolution–alternating least squares (MCR-ALS) analysis. Results of the analysis indicated that among the 22 physico-chemical variables and 14 cyanobacterial taxa measured, the vertical temperature gradient within the water column and nutrient availability were the most powerful explanatory factors for the observed temporal and spatial distribution patterns in the densities of cyanobacterial taxa. The abundance patterns of the dominant cyanobacterial taxa—Aphanocapsa, Aphanothece, Microcystis and Pseudanabaena—were strongly linked with rainfall and run-off patterns into the reservoir, while Coelosphaerium and Microcystis were the taxa most influenced by the apparent occurrence of thermal stratification. The findings demonstrate the capacity of rigorous multivariate data analysis to identify more subtle relationships between water quality variables, catchment factors and cyanobacterial growth in drinking water reservoirs. [ABSTRACT FROM AUTHOR]

Worldwide, the risk profile of drinking water supplies is uniquely shaped by differing geology, climate, and human-based developmental practices. The World Health Organisation's Water Safety Plans (WSPs) are designed to improve the quality of water supplies, particularly regional supplies. One advantage of WSPs is that they are water supply-specific, thus reflecting local conditions; however, WSPs are also limited by a sole focus on health risks, with a little reference to treatment or aesthetic risks such as filter clogging and taste and odour complaints. Appropriately managing these non-health risks is important in effective infrastructure management and in developing consumer trust; however, currently, there is a lack of practical techniques to enable water managers to identify and respond to the threefold-risk profile (health, treatment, and aesthetic) that exists in all regional water supplies. To address this, phytoplankton concentration and bio-volume data were analysed from freshwater samples collected over 2 years, from an ephemeral subtropical catchment in Central Queensland, Australia. This study investigated the temporal and spatial patterns of phytoplankton, as influenced by flow events. Based on field data, a semi-quantitative risk matrix methodology was developed for use as a supplement to the existing WSPs and allows a more comprehensive assessment of phytoplankton-based hazards related to health, treatment (e.g., clogging) and aesthetic risks for individual water supplies. For example, the primary risk identified for the studied catchment was the presence of Cyanobacteria in the pre-chlorinated supply chain immediately prior to entering the treatment plant, specifically Limnothrix redekei. Modelling of the data within these risk matrices demonstrates that the approach is useful in identifying overall catchment risks as well being applied for seasonal and event-based risk assessment of regional drinking water supplies. [ABSTRACT FROM AUTHOR]

n important prediction from game theory is that the value of a resource will influence the level to which an animal is willing to escalate during conflict with conspecific rivals. Here we use this prediction as the rationale for experiments aimed at determining whether escalation decisions made by predators are influenced by the presence of preferred prey. The predators we use are adult individuals of Portia fimbriata, a jumping-spider (Salticidae) species from Queensland (Australia). P. fimbriata is known to prefer other salticid species as prey and can detect the odour of Jacksonoides queenslandicus, this being an especially common salticid species in the Queensland habitat. Here we show that, for P. fimbriata females, the odour of J. queenslandicus primes escalation of vision-based conflict. However, for P. fimbriata males, no comparable effect was found. These findings suggest intrasexual competition for prey is more important to females than to males. [ABSTRACT FROM AUTHOR]

A regulatory model has to meet special criteria for acceptance because it is governed by a legal framework. One of the most important is that concentration estimates from the model have empirical support through evaluation with observations under a variety of situations relevant to regulatory applications. This paper examines two situations in which current models have difficulty meeting this criterion. They are related to 1) surface releases under low wind speed conditions, and 2) prediction of short averaging time concentrations required for odour assessment. This paper analyses the reasons for poor model performance under low wind speeds and provides suggestions on improving current models. The second part of the paper proposes a framework to estimate short concentrations averaged over time scales relevant to odour by using information on statistics comparing observed concentrations to one hour averaged model estimates. Finally, the paper examines some regulatory issues for which we have not yet developed adequate modelling tools. [ABSTRACT FROM AUTHOR]

Emissions from feedlot operations are known to vary by environmental conditions and few if any techniques or models exist to predict the variability of odor emission rates from feedlots. The purpose of this paper is to outline and summarize unpublished reports that are the result of a collective effort to develop industry-specific odor impact criteria for Australian feedlots. This effort used over 250 olfactometry samples collected with a wind tunnel and past research to develop emission models for pads, sediment basins, holding ponds, and manure storage areas over a range of environmental conditions and tested using dynamic olfactometry. A process was developed to integrate these emission models into odor dispersion modeling for the development of impact criteria. The approach used a feedlot hydrology model to derive daily feedlot pad moisture, temperature, and thickness. A submodel converted these daily data to hourly data. A feedlot pad emissions model was developed that predicts feedlot pad emissions as a function of temperature, moisture content, and pad depth. Emissions from sediment basins and holding ponds were predicted using a basin emissions model as a function of days since rain, inflow volume, inflow ratio (pond volume), and temperature. This is the first attempt to model all odor source emissions from a feedlot as variable hourly emissions on the basis of climate, management, and site-specific conditions. Results from the holding pond, sediment basin, and manure storage emission models performed well, but additional work on the pad emissions model may be warranted. This methodology mimics the variable odor emissions and odor impact expected from feedlots due to climate and management effects. The main outcome of the work is the recognition that an industry-specific odor impact criterion must be expressed in terms of all of the components of the assessment methodology. [ABSTRACT FROM AUTHOR]

Coevolution is thought to have led to many small mammal species avoiding the scent marks of their main mammalian predators, as they provide a reliable cue to predation risk. Most support for this hypothesis comes from northern hemisphere predator/prey systems, however, it is unclear whether this avoidance of predator faecal odour occurs in Australia's mammalian fauna, which has evolved in relative isolation from the rest of the world, and is dominated by marsupials rather than placentals. We tested this theory for an Australian system with marsupial and placental predators and prey, that share a long-term (>1 million years) or short-term (<150 years) exposure to each other. The predators were the native marsupial tiger quoll Dasyurus maculatus and the introduced placental red fox Vulpes vulpes. The potential prey were three native rodent species, the bush rat Rattus fuscipes, the swamp rat Rattus lutreolus, the eastern chestnut mouse Pseudomys gracilicaudatus, and the marsupial brown antechinus Antechinus stuartii. Small mammals were captured in Elliott traps with 1/3 of traps treated with fox faeces, 1/3 treated with quoll faeces and the remainder left untreated. The native rodent species all showed avoidance of both tiger quoll and red fox odours whereas the marsupial antechinus showed no responses to either odour. Either predator odour avoidance has not evolved in this marsupial or their reaction to predator odours may be exhibited in ways which are not recognizable through trapping. The avoidance by the rodents of fox odour as well as quoll odour indicates this response may either be due to common components in fox and quoll odour, or it may be a recently evolved response. [ABSTRACT FROM AUTHOR]

The Australian orchid genus Caladenia is unusual in comprising species that have evolved different pollination syndromes, including food deception and sexual deception. In this study, we compare the scent emission of Caladenia longicauda Lindl. (food deceptive), Caladenia arenicola Hopper & A. P. Br. (sexually deceptive), and their putative F1 hybrids to investigate floral scent emission and its changes with the evolution of pollination syndromes. Floral scent was collected with headspace sorption. Odor compounds were identified with gas chromatography-mass spectrometry and quantitative differences analyzed with gas chromatography. Using floral volatiles, the two species could clearly be separated according to their scent profile, with hybrids occupying an intermediate position. The scent profile of the food-deceptive C. longicauda was dominated by benzenoids and isoprenoids, whereas in the sexually deceptive C. arenicola, benzenoids were reduced but fatty acid derivatives elevated. Caladenia longicauda emitted more scent than C. arenicola, both in absolute amount and in number of compounds. The patterns of floral odor emission are discussed in relation to the evolution of pollination syndromes. [ABSTRACT FROM AUTHOR]

Alcoa World Alumina Australia has undertaken comprehensive air emissions monitoring aimed at characterising and quantifying the complete range of emissions to the atmosphere from Bayer refining of alumina at its Western Australian refineries. To the best of our knowledge, this project represents the most complete air emissions inventory of a Bayer refinery conducted in the worldwide alumina industry. It adds considerably to knowledge of air emission factors available for use in emissions estimation required under national pollutant release and transfer registers (NPRTs), such as the Toxic Releases Inventory, USA, and the National Pollutant Inventory, Australia. It also allows the preliminary identification of the key chemical components responsible for characteristic alumina refinery odours and the contribution of these components to the quality, or hedonic tone, of the odours. The strength and acceptability of refinery odours to employees and neighbours appears to be dependent upon where and in what proportion the odorous gases have been emitted from the refineries. This paper presents the results of the programme and develops a basis for classifying the odour properties of the key emission sources in the alumina-refining process. [ABSTRACT FROM AUTHOR]

Domestic food waste (DFW) is an important policy issue because it represents inefficiencies in supply chains and consumption behaviour, creates pressures on urban landfills, and causes downstream environmental impacts such as greenhouse gas (GHG) emissions and odour from landfills. However, the evaluation of proposals to minimise or treat food waste, such as through separate disposal streams, is difficult because those impacts are not registered through normal market price signals. This paper presents non-market valuations for a hypothetical kerbside DFW collection service from a survey of households in two local government areas in the Central Queensland region, Australia. Choice modelling (CM) and contingent valuation methods (CVM) were employed to elicit potential participation and estimate willingness to pay (WTP) of the community for a domestic food waste collection service. Latent class analysis results for the sub-groups supporting an improvement option revealed that cost, odour and fortnightly collection frequency limit both WTP for and participation in the potential kerbside collection program. While there was support because it would extend the lifespans of the local landfills, potential reduction of methane emissions was not a strong driver. No difference in support or willingness to pay could be identified between the two local government populations. While the CVM results showed a WTP of $30.42 and a 58% participation rate for the proposed option, the latent class models showed that potential participation and willingness to pay varied across negative, indifference and positive sub-samples. This study provides a useful example of how a new policy option to improve waste management at a local area level might be evaluated, where the willingness to pay estimates can be factored into a benefit cost analysis and the estimates of likely support or opposition can be inputted into a political economy framework. • The study assessed household preferences to reduce domestic food waste. • Stated preference experiments were used to estimate WTP for reduction options. • Behavioural and attitudinal factors were important in explaining choices. • Two-stage contingent valuation models estimated both participation and WTP. • Latent class analysis models were used to classify responses to key attributes. [ABSTRACT FROM AUTHOR]

Cocoa is an important commodity crop, not only to produce chocolate, one of the most complex products from the sensory perspective, but one that commonly grows in developing countries close to the tropics. This paper presents novel techniques applied using cover photography and a novel computer application (VitiCanopy) to assess the canopy architecture of cocoa trees in a commercial plantation in Queensland, Australia. From the cocoa trees monitored, pod samples were collected, fermented, dried, and ground to obtain the aroma profile per tree using gas chromatography. The canopy architecture data were used as inputs in an artificial neural network (ANN) algorithm, with the aroma profile, considering six main aromas, as targets. The ANN model rendered high accuracy (correlation coefficient (R) = 0.82; mean squared error (MSE) = 0.09) with no overfitting. The model was then applied to an aerial image of the whole cocoa field studied to produce canopy vigor, and aroma profile maps up to the tree-by-tree scale. The tool developed could significantly aid the canopy management practices in cocoa trees, which have a direct effect on cocoa quality. [ABSTRACT FROM AUTHOR]

The article reports on the bio-odors as an environmental pollution in Australia. According to the author, offensive odors are frequently reported pollution in Australia, with several irate calls from communities, and cities. Also, the environmental and health regulatory authorities in Australia have been receiving calls from the public about offensive odors from major cities. These offensive odors said to be always a product of several industrial facilities, wastewater plants, and abattoirs. The author implied that several CASANZ advertisers are experts in detecting, monitoring and treating odor problems.

The article highlights workshops on air dispersion modeling issues and on odor issues within Australia and New Zealand held on May 3, 2005. Short presentations on issues related to odor modeling include draft standard for area source sampling, overview of modeling livestock odors, computational fluid dynamic modeling of dispersion of emissions from a liquid surface at a temperature above ambient air temperature and flux chamber measurements of volatile organic compound emissions. Issues on which there was agreement among the delegates include the Australian Standard for Source Measurements and buoyancy effects from non-point emission sources.

Presents news briefs related to medicine and health as of October 14, 2000. Results of odor discrimination tests among a small sample of health workers; Goals of Australia's national diabetes reduction strategy; Childhood health risks associated with raccoon roundworm, which is found in the fecal material of raccoons; Others.