Into the firing line: civilian ingress during the 2013 Red October bushfires, Australia

A major issue for bushfire management arises when residents decide to leave a safe area and enter the fire zone to rescue or defend their property, pets, loved ones or other assets. Here, we use statistical and narrative analyses of data from an online survey and semi-structured interviews with residents affected by the 2013 Red October bushfires in New South Wales, Australia. The survey results revealed that of the 58 % of respondents who were not at home at the time the threat became apparent, 65 % indicated that they attempted to get home prior to the arrival of the fire front. In doing so, many endangered themselves, their family, friends and emergency services personnel. This paper discusses the shortcomings of bushfire survival plans and official risk communication, which do not cater well for household units that are divided or unattended when a bushfire starts. Findings suggest that to enhance bushfire safety and preparedness, emergency managers should acknowledge and speak more directly to the specific constraints to action for particular social groups at the wildland-urban interface, including families with school-age children, commuters and absentee landholders

Waterlogging increases the infestation level of the pest psyllid Creiis lituratus on Eucalyptus dunnii

The lerp-forming psyllid, Creiis lituratus Froggatt, is the most damaging pest of Eucalyptus dunnii Maiden plantations growing in north-eastern New South Wales. During the past 10 years there have been numerous reports that stands of E. dunnii planted on low-lying areas that were prone to waterlogging were also prone to infestation by C. lituratus. The objective of this shadehouse study was to determine whether C. lituratus prefers young E. dunnii exposed to intermittent waterlogging compared with other treatments (drought, normal watering and a control using normal watering plus an insecticide). Also we assessed whether the nutritional status of E. dunnii foliage, in particular amino acid content, differed between watering treatments. Field-collected C. lituratus adults were released into the shadehouse three months after establishing the watering treatments to individually-potted E. dunnii arranged in a 14 × 6 randomised design. Three months after release of the psyllids, we counted significantly more eggs and nymphs present on the plants subjected to intermittent waterlogging compared with the other treatments. Applying general linear modelling (GLM) and Akaike\u27s information criterion (AIC) we found that the best model included both watering treatment and plant structure (through height and diameter), with psyllid infestation (eggs + nymphs) significantly higher on the waterlogged plants and significantly lower in the drought treatment compared with the normal watering treatment. The application of the generalised estimating equations technique to foliar content of individual amino acids and nutrients did not reveal a clear association with watering treatment or psyllid infestation. Most of the significant differences in amino acid content between treatments were between plants watered normally but with or without the systemic insecticide imidacloprid applied as a soil drench. No eggs or nymphal stages were recorded on the plants treated with imidacloprid. This trial demonstrated that the psyllid C. lituratus has a preference for young E. dunnii subjected to periodic waterlogging. Plantation growers can improve their site-species match for E. dunnii by avoiding sites prone to waterlogging

Germination responses of a dry sclerophyll forest soil-stored seedbank to fire related cues

Fire is an integral component of many ecosystems worldwide. Many plant species require fire-related cues, primarily heat and smoke, to trigger germination. Despite the importance of this process, the responses of many Australian species to these cues are unknown. Without this knowledge fire management strategies may be developed that are inappropriate for individual species and vegetation communities. In this study we examined the responses of a dry sclerophyll forest seed bank to heat and smoke germination cues. Analysis was possible for 48 taxa within the soil seedbank with 34 of these showing a response to one or both of the germination cues. 10 species responded to the heat treatment, 11 species responded to the smoke treatment and 13 species responded to both the heat and smoke treatments. Germination cues acted independently for all species considered. Results in this study were consistent with published reports for most species, although some differences were seen at the species and genus level. The study highlights the importance of fire-related cues in enhancing germination of a large proportion of the species occurring in dry sclerophyll forests

Adaptive monitoring using the endangered northern corroboree frog (Pseudophryne pengilleyi) as a case study

Abstract Monitoring programs are most successful when they undertake regular evaluation of their data to determine if the goals of the programs are achievable and allow changes to achieve this as necessary -so called adaptive monitoring. We use data from a monitoring program for the northern corroboree frog (Pseudophryne pengilleyi), a declining species in south-eastern Australia, to determine the inter-annual variability in the counts and assess what levels of population change would be detectable using different statistical and monitoring approaches. The existing monitoring program would only successfully statistically detect a 3% annual decline (34% total decline) in population size over a ten year period. Monitoring 40 sites would allow an 80% or greater chance of detecting a 2% or greater annual increase over a ten year period (22% increase). Detecting population decreases is more difficult as monitoring 40 sites with a 2% annual decline (19% total decline) will have a less than 40% chance of being detected after 10 years. A larger monitoring program is required to detect smaller annual changes in the population of this species. These findings have implications for the likely effectiveness of other anuran monitoring programs as the northern corroboree frog appears to be far more consistent in detectable call effort compared to most species

Modelling the response of surface fuel to climate change across south-eastern Australia: consequences for future fire regimes

Geophysical Research Abstracts of EGU General Assembly 2014, held 27 April - 2 May, 2014 in Vienna, Austria

Modelling ignition probability for human- and lightning-caused wildfires in Victoria, Australia

Wildfires pose a significant risk to people and property, which is expected to grow with urban expansion into fire-prone landscapes and climate change causing increases in fire extent, severity and frequency. Identifying spatial patterns associated with wildfire activity is important for assessing the potential impacts of wildfires on human life, property and other values. Here, we model the probability of fire ignitions in vegetation across Victoria, Australia, to determine the key drivers of human- and lightning-caused wildfire ignitions. In particular, we extend previous research to consider the role that fuel moisture has in predicting ignition probability while accounting for environmental and local conditions previously identified as important. We used Random Forests to test the effect of variables measuring infrastructure, topography, climate, fuel and soil moisture, fire history, and local weather conditions to investigate what factors drove ignition probability for human- and lightning-caused ignitions. Human-caused ignitions were predominantly influenced by measures of infrastructure and local weather. Lightning-sourced ignitions were driven by fuel moisture, average annual rainfall and local weather. Both human- and lightning-caused ignitions were influenced by dead fuel moisture with ignitions more likely to occur when dead fuel moisture dropped below 20 %. In future, these models of ignition probability may be used to produce spatial likelihood maps, which will improve our models of future wildfire risk and enable land managers to better allocate resources to areas of increased fire risk during the fire season

Cost-effective prescribed burning solutions vary between landscapes in eastern Australia

Fire management agencies undertake a range of fire management strategies in an attempt to reduce the risk posed by future wildfires. This can include fuel treatments (prescribed burning and mechanical removal), suppression and community engagement. However, no agency has an unlimited budget and numerically optimal solutions can rarely be implemented or may not even exist. Agencies are trying to quantify the extent to which their management actions reduce risk across multiple values in the most cost-effective manner. In this paper, we examine the cost-effectiveness of a range of prescribed burning strategies across multiple landscapes in south-eastern Australia. Landscapes considered include vegetated areas surrounding the cities of Hobart, Melbourne, Adelaide, Canberra, and Sydney. Using a simulation approach, we examine the potential range of fires that could occur in a region with varying levels of edge and landscape prescribed burning treatment regimes. Damages to assets are measured for houses, lives, transmission lines, carbon and ecological assets. Costs of treatments are estimated from published models and all data are analyzed using multi-criteria decision analysis. Cost-effectiveness of prescribed burning varies widely between regions. Variations primarily relate to the spatial configuration of assets and natural vegetation. Regions with continuous urban interface adjacent to continuous vegetation had the most cost-effective fuel treatment strategies. In contrast, those regions with fragmented vegetation and discontinuous interfaces demonstrated the lowest cost-effectiveness of treatments. Quantifying the extent to which fuel treatments can reduce the risk to assets is vital for determining the location and extent of treatments across a landscape