The Australian Air Quality Forecasting System: the use of green scenarios of motor vehicle usage as an educational tool

The Australian Air Quality Forecasting System (AAQFS) is one of several newly emerging, high-resolution, numerical air quality forecasting systems. The system is briefly described. A public education application of the air quality impact of motor vehicle usage is explored by computing the concentration and dosage of particulate matter less than 10 microm in aerodynamic diameter (PM10) for a commuter traveling to work between Geelong and Melbourne, Victoria, Australia, under "business-as-usual" and "green" scenarios. This application could be routinely incorporated into systems like AAQFS. Two methodologies for calculating the dosage are described: one for operational use and one for more detailed applications. The Clean Air Research Programme-Personal Exposure Study in Melbourne provides support for this operational methodology. The more detailed methodology is illustrated using a system for predicting concentrations due to near-road emissions of PM10 and applied in Sydney.     

Population structure of humpback whales in the western and central South Pacific Ocean as determined by vocal exchange among populations

For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo‐identification studies. However, the central vocal cluster had higher levels of song‐sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of using culturally transmitted vocal patterns as a way of defining connectivity to infer population structure. We suggest vocal patterns be incorporated by the International Whaling Commission in conjunction with traditional methods in the assessment of structure.     

Global patterns of epipelagic gelatinous zooplankton biomass

There is concern that overfishing may lead to a proliferation of jellyfish through a process known as fishing down the food web. However, there has been no global synthesis of patterns of gelatinous zooplankton biomass (GZB), an important first step in determining any future trends. A meta-analysis of epipelagic-GZB patterns was undertaken, encompassing 58 locations on a global scale, and spanning the years 1967–2009. Epipelagic-GZB decreased strongly with increasing total water column depth (r ² = 0.543, p < 0.001, n = 58): in shallow (<50 m) coastal waters, epipelagic-GZB was typically 742× the levels in deep ocean (>2,000 m) sites. However, the ratio of GZB to primary productivity showed high values across a range of depths, i.e. this measure of the relative abundance of gelatinous zooplankton did not co-vary with depth.     

A survey of forest workers in New Zealand. Do hours of work, rest, and recovery play a role in accidents and injury?

PROBLEM: A number of structural and organizational changes have occurred recently within the New Zealand Forestry Industry, with concerns being raised about the impact of these changes on the forestry worker in terms of fatigue, sleepiness, and compromised safety. This study explored the relationship of fatigue, and some of its key determinants, with accidents and injuries in a group of forestry industry workers in New Zealand. METHOD: A total of 367 forestry workers responded to a self-administered questionnaire. RESULTS: Fatigue was found to be commonly experienced at work in the forest, with 78% of workers reporting that they experienced fatigue at least "sometimes." This study found that certain groups of workers reported long working hours, reduced sleep, compromised recovery time, and intensely paced work. The results of logistic regression analysis showed that recent sleep, number of breaks taken during the workday, and specific job/tasks were independently associated with reporting of high fatigue levels at work. Near-miss injury events were significantly more common among those reporting a high level of fatigue at work. Accidents and lost-time injury were associated with length of time at work, ethnicity, and having had near-miss injury events. DISCUSSION: Together, these results suggest that fatigue and aspects of work organization, which are likely to be fatiguing, may be associated with compromised safety for forest workers. IMPACT ON INDUSTRY: With an already slim margin of error present in forest operations, an impairment due to increased fatigue may constitute a significant risk factor for accidents and injuries in this workforce. The results indicate the need for further examination of shift and workload management among forestry workers, as well as a role for improving industry awareness about the causes and consequences of fatigue.     

Digit length ratio (2D/4D): comparing measurements from X-rays and photographs in field voles (<Emphasis Type="Italic">Microtus agrestis</Emphasis>)

The ratio of second-to-fourth digit length (2D/4D) has been suggested to be a useful adult age marker of intrauterine exposure to steroids because it should be sexually dimorphic and fixed already in utero. Numerous studies mainly on humans have supported this conclusion, but it is yet unclear how well this applies to other vertebrates. This information would be especially valuable to field biologists to whom measuring steroids in utero is often impossible. The non-human studies conducted so far have yielded inconsistent results, perhaps due to the variety of different methods employed in measuring 2D/4D. We examined the age and sex dependency and lateral asymmetry of 2D/4D in field voles (Microtus agrestis) and compared whether these effects differed between 2D/4D measurements taken from photographs and X-rays. Our results show that 2D/4D measurements from photos had a higher measurement error and gave consistently higher 2D/4D than those from X-rays. According to both measurement methods, the right paw showed higher 2D/4D values than the left paw (lateral asymmetry). Adult voles had a lower 2D/4D than juveniles when measured from X-rays, but not when measured from photographs. We found no evidence for a sex difference in 2D/4D using either of the measurement methods. Our findings thus suggest that X-rays, due to their greater accuracy, should be preferred over photographs for measuring digit ratios in rodents. Our results also indicate that in this species, 2D/4D is laterally asymmetric, but it may not be either fixed in utero or sexually dimorphic. In conclusion, 2D/4D appears to be a rather species- and method-specific measure and researchers should be careful when generalising its applicability to study early hormonal effects in vertebrates.     

Associations of plant fitness, leaf chemistry, and damage suggest selection mosaic in plant-herbivore interactions

The geographic mosaic theory of coevolution states that variation in species interactions forms the raw material for coevolutionary processes, which take place over large geographic scales. One key assumption underlying the process of coevolution in plant-herbivore interactions is that herbivores exert selection on their host plants and that this selection varies among plant populations. We examined spatial variation in the existence and strength of phenotypic selection on host plant resistance exerted by specialist herbivores in 17 archipelago populations of the perennial herb Vincetoxicum hirundinaria (Asclepiadaceae). In these highly fragmented populations, V. hirundinaria is consumed by the larvae of two specialist herbivores: the folivorous moth Abrostola asclepiadis and the seed predator Euphranta connexa. Selection imposed on host plants by these herbivores was examined by analyzing the associations between levels of herbivory, plant fitness, and contents of a number of leaf chemicals reflecting plant resistance to and quality for the herbivores. We found extensive spatial variation in the levels of herbivory and in plant fitness. More importantly, the impact of both leaf herbivory and seed predation on plant fitness varied among plant populations, indicating spatial variation in phenotypic selection. In addition, leaf chemistry varied widely among plant populations, reflecting spatial variation in plant quality as food for the herbivores. However, leaf compounds influenced folivory similarly in all the studied plant populations, and interestingly, some of the compounds were associated with the intensity of seed predation. Finally, some of the leaf compounds were associated with plant fitness, and the strength and direction of these associations varied among plant populations. The observed spatial variation in the strength of the interactions between V. hirundinaria and its specialist herbivores suggests a geographic selection mosaic. Because the occurrence and strength of spatial variation varied between the two specialist herbivores, our results highlight the importance of considering multiple enemies when trying to understand evolution of interactions between plants and their herbivores.     

The sex pheromone of the grain aphid,Sitobion avenae (Fab.) (Homoptera,Aphididae)

Summary The sex pheromone of the grain aphid,Sitobion avenae (Fab.), is identified as (4aS,7S,7aR)-nepetalactone, for which specific olfactory cells are located in the secondary rhinaria of the male antenna. The related (1R,4aS,7S,7aR)-nepetalactol was not produced by females in significant amounts (ca 10,000-fold less than the nepetalactone), although cells in the male antenna were found that responded specifically to this compound. Behavioural activity in the linear track ol-factometer showed attraction of males to the nepetalactone, but not to the nepetalactol.     

Cooling of bat hibernacula to mitigate white-nose syndrome

White-nose syndrome (WNS) is a fungal disease that has caused precipitous declines in several North American bat species, creating an urgent need for conservation. We examined how microclimates and other characteristics of hibernacula have affected bat populations following WNS-associated declines and evaluated whether cooling of warm, little-used hibernacula could benefit bats. During the period following mass mortality (2013–2020), we conducted 191 winter surveys of 25 unmanipulated hibernacula and 6 manipulated hibernacula across Pennsylvania (USA). We joined these data with additional datasets on historical (pre-WNS) bat counts and on the spatial distribution of underground sites. We used generalized linear mixed models and model selection to identify factors affecting bat populations. Winter counts of Myotis lucifugus were higher and increased over time in colder hibernacula (those with midwinter temperatures of 3–6 °C) compared with warmer (7–11 °C) hibernacula. Counts of Eptesicus fuscus, Myotis leibii, and Myotis septentrionalis were likewise higher in colder hibernacula (temperature effects = –0.73 [SE 0.15], –0.51 [0.18], and –0.97 [0.28], respectively). Populations of M. lucifugus and M. septentrionalis increased most over time in hibernacula surrounded by more nearby sites, whereas Eptesicus fuscus counts remained high where they had been high before WNS onset (pre-WNS high count effect = 0.59 [0.22]). Winter counts of M. leibii were higher in hibernacula with high vapor pressure deficits (VPDs) (particularly over 0.1 kPa) compared with sites with lower VPDs (VPD effect = 15.3 [4.6]). Counts of M. lucifugus and E. fuscus also appeared higher where VPD was higher. In contrast, Perimyotis subflavus counts increased over time in relatively warm hibernacula and were unaffected by VPD. Where we manipulated hibernacula, we achieved cooling of on average 2.1 °C. At manipulated hibernacula, counts of M. lucifugus and P. subflavus increased over time (years since manipulation effect = 0.70 [0.28] and 0.51 [0.15], respectively). Further, there were more E. fuscus where cooling was greatest (temperature difference effect = –0.46 [SE 0.11]), and there was some evidence there were more P. subflavus in hibernacula sections that remained warm after manipulation. These data show bats are responding effectively to WNS through habitat selection. In M. lucifugus, M. septentrionalis, and possibly P. subflavus, this response is ongoing, with bats increasingly aggregating at suitable hibernacula, whereas E. fuscus remain in previously favored sites. Our results suggest that cooling warm sites receiving little use by bats is a viable strategy for combating WNS.