Forest restoration in a time of fire: perspectives from tall, wet eucalypt forests subject to stand-replacing wildfires

Wildfires have the potential to add considerably to the already significant challenge of achieving effective forest restoration in the UN Decade on Ecosystem Restoration. While fire can sometimes promote forest restoration (e.g. by creating otherwise rare, early successional habitats), it can thwart it in others (e.g. by depleting key patch types and stand structures). Here we outline key considerations in facilitating restoration of some tall wet temperate forest ecosystems and some boreal forest ecosystems where the typical fire regime is rare high-severity stand-replacing fire. Some of these ecosystems are experiencing altered fire regimes such as increased fire extent, severity and/or frequency. Achieving good restoration outcomes in such ecosystems demands understanding fire regimes and their impacts on vegetation and other elements of biodiversity and then selecting ecosystem-appropriate management interventions. Potential actions range from doing nothing (as the ecosystem already maintains full post-fire regenerative capacity) to interventions prior to a conflagration like prescribed burning to limit the risks of high-severity fire, excluding activities that impair post-fire recovery (e.g. post-fire logging), and artificial seeding where natural regeneration fails. The most ecologically effective actions will be ecosystem-specific and context-specific and informed by knowledge of the ecosystem in question (such as plant life-history attributes) and inter-relationships with attributes like vegetation condition at the time it is burnt (e.g. young versus old forest). This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.

72 Evaluation of digital images of bovine embryos

Bovine embryo transfer is an assisted reproductive technology that enables cattle producers to reach their reproductive, genetic, and financial goals. Proper evaluation of embryo quality and developmental stage is key to the success of the embryo transfer industry and is often acquired “on the job” as there are few embryo evaluation training opportunities. The goals of this project were to develop a bank of digital images of invivo-produced bovine embryos, and to evaluate interrater reliability and variation of grade and stage scores and the assessment of the integrity of the zona pellucida (ZP) using an online platform. Frozen/thawed bovine embryos (Day 7) were placed in a commercially available holding medium, and images were captured using a high-resolution camera (112× magnification). Survey participants (n=89) responded to questions on demographic and embryo evaluation experience and assigned grades and stages and evaluated the integrity of the ZP in 58 embryo images (the IETS embryo evaluation rubric was provided). The variation among raters within and between demographic categories was analysed using the “kappaetc” package with weights for ordinal variables (grade and stage) in Stata version 14.2 (StataCorp). The Kruskal–Wallis test was used to assess whether variation [measured as interquartile range (IQR)] in grade and stage ratings within individual were significantly different (P=0.05) by demographic factors. Overall, interrater reliability (measured by Cohen’s Kappa, κ) for stage was moderate (κ=0.57), whereas identification of grade and the ZP was substantial (κ=0.69 and 0.73, respectively). Interrater reliability for grade was significantly lower among those with ≤2 years (n=17) of experience (κ=0.44) compared with those having 3–9 years (n=29; κ=0.57) and ≥10 years (n=43; κ=0.64). Similarly, interrater agreement for stage was significantly lower for those with ≤2 years of experience (κ=0.58) compared with those having 3–9 years (κ=0.68) and ≥10 years (κ=0.75). Interrater agreement for stage was higher for those who did not use the IETS rubric compared with those who did (κ=0.73 vs. κ=0.63, respectively), and the variability was highest for Stage 6 and lowest for Stage 4 embryos. No demographic variables were significantly associated with interrater reliability for the integrity of the ZP. The variability of stage ratings (IQR) within individual significantly increased with more years of experience, with greatest IQR among those with ≥10 years of experience. The IQR within individual for grade decreased with increasing length of time rating, with the lowest IQR for the longest duration spent on rating the embryos. Overall, there was a moderate to substantial interrater agreement in embryo evaluation, which increased with experience. Further, evaluation of bovine embryo digital images may be a useful training tool instead of or in conjunction with a “hands-on” experience. Future surveys will involve multiple images of the same embryo and video to enhance the evaluation process and increase interrater reliability.

12 Artificial insemination and embryo transfer results in ewes during a long daylength period

Sheep are polyestrous, short-day breeders (∼11h of daylength), and exhibit oestrus approximately every 16–17 days during the breeding season, usually in late September to late December in the Northern Hemisphere. Progressive sheep producers often use assisted reproductive techniques such as laparoscopic AI and ovarian hyper-stimulation, embryo collection, and embryo transfer (ET) to increase genetic gain, and strive to have early December lambs to target specific show markets, which dictates AI or ET during the late summer. This field trial compared pregnancy rates following AI or ET in July and August (∼14h of daylength) in southwest Virginia (36–38′12″ N). Ewes (AI, n=83; ET recipients, n=33) were synchronized using a modified Ovsynch protocol involving intravaginal progesterone implants for 14 days, prostaglandin F2α (intramuscular) 48h before expected oestrus, and PG600 (IM) and gonadotrophin-releasing hormone (intramuscular) 52 to 54h and 16h before AI, respectively. Ewes were subjected to AI (frozen/thawed semen) regardless of whether they displayed signs of oestrus, and ewes selected as embryo recipients were subjected to a similar protocol but instead received 1 or 2 embryos (based upon the number of viable embryos produced per embryo donor) 6 days following the AI of the embryo donors. Ovarian hyper-stimulation of the embryo donors (n=13) was enabled by twice-daily FSH injections [totalling 350–455IU of Folltropin V (10–13mL)] for the 4 days before AI. Six days following AI, embryos were recovered surgically from the embryo donors (n=13) and yielded an average (±s.e.m.) of 6.6±1.2 total ova, 4.7±1.1 transferable quality embryos, and 1.9±0.8 unfertilized ova per collection. Pregnancy was detected using transrectal ultrasonography at ∼30 days of gestation and the pregnancy rates were analysed using Chi-squared. There was a tendency (P=0.092) for more pregnancies to be established following ET (22/33; 66%) compared with AI (41/83; 49%). There was no statistical relationship between AI ewes or ET recipient ewes that became pregnant relative to whether they displayed signs of oestrus or not. Embryo transfer was a more successful approach to produce pregnancies in ewes compared with AI during long daylength periods in this field trial. Further, ova from hyper-stimulated embryo donor ewes experienced a very high fertilization rate. Future studies will evaluate the ova capability directly via laparoscopic aspiration of ovarian follicles and IVF and evaluation of hyper- and non-hyper-stimulated follicular waves (using transrectal ultrasonography) and endocrine dynamics during different long and short daylength periods. Extending the opportunity to generate embryos and offspring regardless of daylength will assist aggressive sheep producers in reaching their reproductive, financial, and genetic goals.

Reference state and benchmark concepts for better biodiversity conservation in contemporary ecosystems

Measuring the status and trends of biodiversity is critical for making informed decisions about the conservation, management or restoration of species, habitats and ecosystems. Defining the reference state against which status and change are measured is essential. Typically, reference states describe historical conditions, yet historical conditions are challenging to quantify, may be difficult to falsify, and may no longer be an attainable target in a contemporary ecosystem. We have constructed a conceptual framework to help inform thinking and discussion around the philosophical underpinnings of reference states and guide their application. We characterize currently recognized historical reference states and describe them as Pre-Human, Indigenous Cultural, Pre-Intensification and Hybrid-Historical. We extend the conceptual framework to include contemporary reference states as an alternative theoretical perspective. The contemporary reference state framework is a major conceptual shift that focuses on current ecological patterns and identifies areas with higher biodiversity values relative to other locations within the same ecosystem, regardless of the disturbance history. We acknowledge that past processes play an essential role in driving contemporary patterns of diversity. The specific context for which we design the contemporary conceptual frame is underpinned by an overarching goal-to maximize biodiversity conservation and restoration outcomes in existing ecosystems. The contemporary reference state framework can account for the inherent differences in the diversity of biodiversity values (e.g. native species richness, habitat complexity) across spatial scales, communities and ecosystems. In contrast to historical reference states, contemporary references states are measurable and falsifiable. This 'road map of reference states' offers perspective needed to define and assess the status and trends in biodiversity and habitats. We demonstrate the contemporary reference state concept with an example from south-eastern Australia. Our framework provides a tractable way for policy-makers and practitioners to navigate biodiversity assessments to maximize conservation and restoration outcomes in contemporary ecosystems.

An evaluation of the EOLAS psychoeducation programme for service users: An innovative approach to collaboration between clinicians and ‘experts by experience’

Introduction

Psychoeducation for service users has been shown in several recent meta-analyses to improve adherence with treatment, decrease rehospitalization rates and improve various measures of quality of life. The 8-week EOLAS Programme for service users with schizophrenia or bipolar disorder is unique in being designed, co-facilitated and evaluated collaboratively by both clinician and peer representatives. EOLAS forms part of the service plan of the national Health Service in Ireland.

Aims and objectives

To evaluate the impact of the EOLAS programme on participants’ perceived knowledge, confidence, advocacy, recovery attitudes and hope.

Methodology

Anonymised questionnaires were administered to participants before and after completion of the EOLAS Programme.

All survey participants were invited to attend for interview to examine qualitatively their experience of the programme. Interviews were recorded and subjected to thematic analysis.

Results

Forty-five subjects completed pre- and post-programme questionnaires (participation rate = 55%).

Significant improvements (P < 0.05) were identified across each of the 5 domains examined (i.e. perceived knowledge, confidence, advocacy, recovery attitudes, hope). Expressed satisfaction with the programme was high (95%).

At interview, participants (n = 12) particularly valued:

– the opportunity to ask questions of the psychiatrist e.g. about medication;

– improving self-care skills e.g. monitoring early warning signs of relapse;

– co-facilitation by a peer, which provided extra credibility and inspired hope;

– sharing experiences with peers.

Conclusions

The EOLAS programme succeeds in meeting the needs of the participants across the target domains. This success depends on the unique collaboration between clinicians and peer experts on which EOLAS is based.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Building selection by the common brushtail possum (Trichosurus vulpecula)

Abstract ContextThe common brushtail possum (Trichosurus vulpecula) is a protected native species in Australia that can access buildings in urban areas and cause considerable damage or disruption to building occupants. Although several strategies to discourage this species from entering buildings have been recommended, few have been evaluated empirically. AimsOur study aims to analyse how landscaping and building construction influence occupancy of buildings by the common brushtail possum. MethodsWe collated reports of possums occupying 134 buildings over 12 years on the campus of The Australian National University (ANU), in the Australian Capital Territory (ACT). We used generalised linear modelling (GLM) to identify associations between the total number of reported possum-related incidents for buildings and a range of landscape and building characteristics. Key resultsControlling for the effect of building size, we found that the number of reported possum-related incidents in buildings was positively associated with the percentage of tree and shrub canopy cover within the calculated home-range buffer distance of 49m from buildings, length of canopy overhanging roofs and building age, and negatively associated with tree species richness and number of trees with natural hollows and nest boxes within 49m of buildings. There were likely to be more possum-related reports from buildings in areas where the dominant tree genus was native, buildings with parapets (walls extending above the roof), buildings with structures penetrating from the roof, buildings with tile roofs and gable roofs. ConclusionsA combination of suitable habitat surrounding buildings, suitable access to the roofs of buildings and weak points in building roofs (e.g. parapets, roof penetrations), makes them more vulnerable to occupancy by the common brushtail possum. Implications Our results provided clues for managing existing buildings, or designing new buildings, in a way that may reduce the likelihood of occupancy by the common brushtail possum. Our study also demonstrated how building-maintenance records can be used to address human–wildlife conflict over time.

The disproportionate importance of long-unburned forests and woodlands for reptiles

Our understanding of the impacts of time since fire on reptiles remains limited, partly because there are relatively few locations where long-term, spatially explicit fire histories are available. Such information is important given the large proportion of some landscapes that are managed with frequent prescribed fire to meet fuel management objectives. We conducted a space-for-time study across a landscape in southeastern Australia where the known fire history spanned 6 months to at least 96 years. Four methods were used to survey reptiles in 81 forest and woodland sites to investigate how time since fire (TSF), habitat, and environmental variables affect reptile richness, abundance, and composition. We used generalized linear models, generalized linear mixed-effects models, PERMANOVA, and SIMPER to identify relationships between the reptile assemblage (richness, abundance, and composition, respectively) and TSF, habitat, and environmental variables. All three reptile metrics were associated with TSF. Reptile richness and abundance were significantly higher in sites >96 years postfire than younger fire ages (0.5-12 years). Reptile composition at long-unburned sites was dissimilar to sites burned more recently but was similar between sites burned 0.5-2 and 6-12 years prior to sampling. Synthesis and applications. Long-unburned forests and woodlands were disproportionately more important for reptile richness and abundance than areas burned 6 months to 12 years prior to sampling. This is important given that long-unburned areas represent <8% of our study area. Our results therefore suggest that reptiles would benefit from protecting remaining long-unburned areas from fire and transitioning a greater proportion of the study area to long-unburned. However, some compositional differences between the long-unburned sites and sites 0.5-12 years postfire indicate that maintaining a diversity in fire ages is important for conserving reptile diversity.

Outcomes from 10 years of biodiversity offsetting

We quantified net changes to the area and quality of native vegetation after the introduction of biodiversity offsetting in New South Wales, Australia-a policy intended to "prevent broad-scale clearing of native vegetation unless it improves or maintains environmental values." Over 10 years, a total of 21,928 ha of native vegetation was approved for clearing under this policy and 83,459 ha was established as biodiversity offsets. We estimated that no net loss in the area of native vegetation under this policy will not occur for 146 years. This is because 82% of the total area offset was obtained by averting losses to existing native vegetation and the rate that these averted losses accrue was over-estimated in the policy. There were predicted net gains in 10 of the 14 attributes used to assess the quality of habitat. An overall net gain in the quality of habitat was assessed under this policy by substituting habitat attributes that are difficult to restore (e.g. mature trees) with habitat attributes for which restoration is relatively easy (e.g. tree seedlings). Long-term rates of annual deforestation did not significantly change across the study area after biodiversity offsetting was introduced. Overall, the policy examined here provides no net loss of biodiversity: (i) many generations into the future, which is not consistent with intergenerational equity; and (ii) by substituting different habitat attributes, so gains are not equivalent to losses. We recommend a number of changes to biodiversity offsetting policy to overcome these issues.

Evaluating complementary networks of restoration plantings for landscape-scale occurrence of temporally dynamic species

Multibillion dollar investments in land restoration make it critical that conservation goals are achieved cost-effectively. Approaches developed for systematic conservation planning offer opportunities to evaluate landscape-scale, temporally dynamic biodiversity outcomes from restoration and improve on traditional approaches that focus on the most species-rich plantings. We investigated whether it is possible to apply a complementarity-based approach to evaluate the extent to which an existing network of restoration plantings meets representation targets. Using a case study of woodland birds of conservation concern in southeastern Australia, we compared complementarity-based selections of plantings based on temporally dynamic species occurrences with selections based on static species occurrences and selections based on ranking plantings by species richness. The dynamic complementarity approach, which incorporated species occurrences over 5 years, resulted in higher species occurrences and proportion of targets met compared with the static complementarity approach, in which species occurrences were taken at a single point in time. For equivalent cost, the dynamic complementarity approach also always resulted in higher average minimum percent occurrence of species maintained through time and a higher proportion of the bird community meeting representation targets compared with the species-richness approach. Plantings selected under the complementarity approaches represented the full range of planting attributes, whereas those selected under the species-richness approach were larger in size. Our results suggest that future restoration policy should not attempt to achieve all conservation goals within individual plantings, but should instead capitalize on restoration opportunities as they arise to achieve collective value of multiple plantings across the landscape. Networks of restoration plantings with complementary attributes of age, size, vegetation structure, and landscape context lead to considerably better outcomes than conventional restoration objectives of site-scale species richness and are crucial for allocating restoration investment wisely to reach desired conservation goals.

Using offsets to mitigate environmental impacts of major projects: A stakeholder analysis

Global patterns of development suggest that as more projects are initiated, business will need to find acceptable measures to conserve biodiversity. The application of environmental offsets allows firms to combine their economic interests with the environment and society. This article presents the results of a multi-stakeholder analysis related to the design of offsets principles, policies, and regulatory processes, using a large infrastructure projects context. The results indicate that business was primarily interested in using direct offsets and other compensatory measures, known internationally as indirect offsets, to acquit their environmental management obligations. In contrast, the environmental sector argued that highly principled and scientifically robust offsets programs should be implemented and maintained for enduring environmental protection. Stakeholder consensus stressed the importance of offsets registers with commensurate monitoring and enforcement. Our findings provide instructive insights into the countervailing views of offsets policy stakeholders.

Fine-Scale Habitat Heterogeneity Influences Occupancy in Terrestrial Mammals in a Temperate Region of Australia

Vegetation heterogeneity is an inherent feature of most ecosystems, characterises the structure of habitat, and is considered an important driver of species distribution patterns. However, quantifying fine-scale heterogeneity of vegetation cover can be time consuming, and therefore it is seldom measured. Here, we determine if heterogeneity is worthwhile measuring, in addition to the amount of cover, when examining species distribution patterns. Further, we investigated the effect of the surrounding landscape heterogeneity on species occupancy. We tested the effect of cover and heterogeneity of trees and shrubs, and the context of the surrounding landscape (number of habitats and distance to an ecotone) on site occupancy of three mammal species (the black wallaby [Wallabia bicolor], the long-nosed bandicoot [Perameles nasuta], and the bush rat [Rattus fuscipes]) within a naturally heterogeneous landscape in a temperate region of Australia. We found that fine-scale heterogeneity of vegetation attributes is an important driver of mammal occurrence of two of these species. Further, we found that, although all three species responded positively to vegetation heterogeneity, different mammals vary in their response to different types of vegetation heterogeneity measurement. For example, the black wallaby responded to the proximity of an ecotone, and the bush rat and the long-nosed bandicoot responded to fine-scale heterogeneity of small tree cover, whereas none of the mammals responded to broad scale heterogeneity (i.e., the number of habitat types). Our results highlight the influence of methodological decisions, such as how heterogeneity vegetation is measured, in quantifying species responses to habitat structures. The findings confirm the importance of choosing meaningful heterogeneity measures when modelling the factors influencing occupancy of the species of interest.

The future of large old trees in urban landscapes

Large old trees are disproportionate providers of structural elements (e.g. hollows, coarse woody debris), which are crucial habitat resources for many species. The decline of large old trees in modified landscapes is of global conservation concern. Once large old trees are removed, they are difficult to replace in the short term due to typically prolonged time periods needed for trees to mature (i.e. centuries). Few studies have investigated the decline of large old trees in urban landscapes. Using a simulation model, we predicted the future availability of native hollow-bearing trees (a surrogate for large old trees) in an expanding city in southeastern Australia. In urban greenspace, we predicted that the number of hollow-bearing trees is likely to decline by 87% over 300 years under existing management practices. Under a worst case scenario, hollow-bearing trees may be completely lost within 115 years. Conversely, we predicted that the number of hollow-bearing trees will likely remain stable in semi-natural nature reserves. Sensitivity analysis revealed that the number of hollow-bearing trees perpetuated in urban greenspace over the long term is most sensitive to the: (1) maximum standing life of trees; (2) number of regenerating seedlings ha⁻¹; and (3) rate of hollow formation. We tested the efficacy of alternative urban management strategies and found that the only way to arrest the decline of large old trees requires a collective management strategy that ensures: (1) trees remain standing for at least 40% longer than currently tolerated lifespans; (2) the number of seedlings established is increased by at least 60%; and (3) the formation of habitat structures provided by large old trees is accelerated by at least 30% (e.g. artificial structures) to compensate for short term deficits in habitat resources. Immediate implementation of these recommendations is needed to avert long term risk to urban biodiversity.

Urbanization impacts on mammals across urban-forest edges and a predictive model of edge effects

With accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. We explored the effects of high and low-density housing developments on forest-dwelling mammals. Based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. We surveyed arboreal mammals in sites of high and low housing density along 600 m transects that spanned urban areas and areas turn on adjacent native forest. We also surveyed forest controls to test whether edge effects extended beyond our edge transects. We fitted models describing richness, total abundance and individual species abundance. Low-density housing developments provided suitable habitat for most arboreal mammals. In contrast, high-density housing developments had lower species richness, total abundance and individual species abundance, but supported the highest abundances of an urban adapter (Trichosurus vulpecula). We did not find the predicted gradual decline in species abundance. Of four species analysed, three exhibited no response to the proximity of urban boundaries, but spilled over into adjacent urban habitat to differing extents. One species (Petaurus australis) had an extended negative response to urban boundaries, suggesting that urban development has impacts beyond 300 m into adjacent forest. Our empirical work demonstrates that high-density housing developments have negative effects on both community and species level responses, except for one urban adapter. We developed a new predictive model of edge effects based on our results and the literature. To predict animal responses across edges, our framework integrates for first time: (1) habitat quality/preference, (2) species response with the proximity to the adjacent habitat, and (3) spillover extent/sensitivity to adjacent habitat boundaries. This framework will allow scientists, managers and planners better understand and predict both species responses across edges and impacts of development in mosaic landscapes.

Environmental reporting and accounting in Australia: progress, prospects and research priorities

Despite strong demand for information to support the sustainable use of Australia's natural resources and conserve environmental values and despite considerable effort and investment, nation-wide environmental data collection and analysis remains a substantially unmet challenge. We review progress in producing national environmental reports and accounts, identify challenges and opportunities, and analyse the potential role of research in addressing these. Australia's low and concentrated population density and the short history since European settlement contribute to the lack of environmental data. There are additional factors: highly diverse data requirements and standards, disagreement on information priorities, poorly measurable management objectives, lack of coordination, over-reliance on researchers and businesses for data collection, lack of business engagement, and short-term, project-based activities. New opportunities have arisen to overcome some of these challenges: enhanced monitoring networks, standardisation, data management and modelling, greater commitment to share and integrate data, community monitoring, increasing acceptance of environmental and sustainability indicators, and progress in environmental accounting practices. Successes in generating climate, water and greenhouse gas information appear to be attributable to an unambiguous data requirement, considerable investment, and legislative instruments that enhance data sharing and create a clearly defined role for operational agencies. Based on the analysis presented, we suggest six priorities for research: (1) common definitions and standards for information that address management objectives, (2) ecological measures that are scalable from local to national level, (3) promotion of long-term data collection and reporting by researchers, (4) efficient satellite and sensor network technologies and data analysis methods, (5) environmental modelling approaches that can reconcile multiple data sources, and (6) experimental accounting to pursue consistent, credible and relevant information structures and to identify new data requirements. Opportunities exist to make progress in each of these areas and help secure a more sustainable future.

Cross-sectional and temporal relationships between bird occupancy and vegetation cover at multiple spatial scales

Scale is a key concept in ecology, but the statistically based quantification of scale effects has often proved difficult. This is exemplified by the challenges of quantifying relationships between biodiversity and vegetation cover at different spatial scales to guide restoration and conservation efforts in agricultural environments. We used data from 2002 to 2010 on 184 sites (viz., site scale) nested within 46 farms (the farm scale), nested within 23 landscapes (the landscape scale). We found cross-sectional relationships with the amount of vegetation cover that were typically positive for woodland birds and negative for open-country birds. However, for some species, relationships differed between spatial scales, suggesting differences in nesting and foraging requirements. There was a 3.5% increase in the amount of native vegetation cover in our study region between 2002 and 2010, and our analyses revealed that some open country species responded negatively to these temporal changes, typically at the farm and/or site scale, but not the landscape scale. Species generally exhibited stronger cross-sectional relationships with the amount of vegetation cover than relationships between changes in occupancy and temporal changes in vegetation cover. This unexpected result can be attributed to differences in habitat use by birds of existing vegetation cover (typically old-growth woodland) vs. plantings and natural regeneration, which are the main contributors to temporal increases in vegetation cover. By taking a multi-scaled empirical approach, we have identified species-specific, scale-dependent responses to vegetation cover. These findings are of considerable practical importance for understanding which species will respond to different scales of protection of existing areas of native vegetation, efforts to increase the amount of native vegetation over time, and both approaches together.

Effect of planning for connectivity on linear reserve networks

Although the concept of connectivity is decades old, it remains poorly understood and defined, and some argue that habitat quality and area should take precedence in conservation planning instead. However, fragmented landscapes are often characterized by linear features that are inherently connected, such as streams and hedgerows. For these, both representation and connectivity targets may be met with little effect on the cost, area, or quality of the reserve network. We assessed how connectivity approaches affect planning outcomes for linear habitat networks by using the stock-route network of Australia as a case study. With the objective of representing vegetation communities across the network at a minimal cost, we ran scenarios with a range of representation targets (10%, 30%, 50%, and 70%) and used 3 approaches to account for connectivity (boundary length modifier, Euclidean distance, and landscape-value [LV]). We found that decisions regarding the target and connectivity approach used affected the spatial allocation of reserve systems. At targets ≥50%, networks designed with the Euclidean distance and LV approaches consisted of a greater number of small reserves. Hence, by maximizing both representation and connectivity, these networks compromised on larger contiguous areas. However, targets this high are rarely used in real-world conservation planning. Approaches for incorporating connectivity into the planning of linear reserve networks that account for both the spatial arrangement of reserves and the characteristics of the intervening matrix highlight important sections that link the landscape and that may otherwise be overlooked.

Interacting factors driving a major loss of large trees with cavities in a forest ecosystem

Large trees with cavities provide critical ecological functions in forests worldwide, including vital nesting and denning resources for many species. However, many ecosystems are experiencing increasingly rapid loss of large trees or a failure to recruit new large trees or both. We quantify this problem in a globally iconic ecosystem in southeastern Australia – forests dominated by the world's tallest angiosperms, Mountain Ash (Eucalyptus regnans). Tree, stand and landscape-level factors influencing the death and collapse of large living cavity trees and the decay and collapse of dead trees with cavities are documented using a suite of long-term datasets gathered between 1983 and 2011. The historical rate of tree mortality on unburned sites between 1997 and 2011 was >14% with a mortality spike in the driest period (2006–2009). Following a major wildfire in 2009, 79% of large living trees with cavities died and 57–100% of large dead trees were destroyed on burned sites. Repeated measurements between 1997 and 2011 revealed no recruitment of any new large trees with cavities on any of our unburned or burned sites. Transition probability matrices of large trees with cavities through increasingly decayed condition states projects a severe shortage of large trees with cavities by 2039 that will continue until at least 2067. This large cavity tree crisis in Mountain Ash forests is a product of: (1) the prolonged time required (>120 years) for initiation of cavities; and (2) repeated past wildfires and widespread logging operations. These latter factors have resulted in all landscapes being dominated by stands ≤72 years and just 1.16% of forest being unburned and unlogged. We discuss how the features that make Mountain Ash forests vulnerable to a decline in large tree abundance are shared with many forest types worldwide.

Not all kinds of revegetation are created equal: revegetation type influences bird assemblages in threatened Australian woodland ecosystems

The value for biodiversity of large intact areas of native vegetation is well established. The biodiversity value of regrowth vegetation is also increasingly recognised worldwide. However, there can be different kinds of revegetation that have different origins. Are there differences in the richness and composition of biotic communities in different kinds of revegetation? The answer remains unknown or poorly known in many ecosystems. We examined the conservation value of different kinds of revegetation through a comparative study of birds in 193 sites surveyed over ten years in four growth types located in semi-cleared agricultural areas of south-eastern Australia. These growth types were resprout regrowth, seedling regrowth, plantings, and old growth. Our investigation produced several key findings: (1) Marked differences in the bird assemblages of plantings, resprout regrowth, seedling regrowth, and old growth. (2) Differences in the number of species detected significantly more often in the different growth types; 29 species for plantings, 25 for seedling regrowth, 20 for resprout regrowth, and 15 for old growth. (3) Many bird species of conservation concern were significantly more often recorded in resprout regrowth, seedling regrowth or plantings but no species of conservation concern were recorded most often in old growth. We suggest that differences in bird occurrence among different growth types are likely to be strongly associated with growth-type differences in stand structural complexity.Our findings suggest a range of vegetation growth types are likely to be required in a given farmland area to support the diverse array of bird species that have the potential to occur in Australian temperate woodland ecosystems. Our results also highlight the inherent conservation value of regrowth woodland and suggest that current policies which allow it to be cleared or thinned need to be carefully re-examined.

Land management practices associated with house loss in wildfires

Losses to life and property from unplanned fires (wildfires) are forecast to increase because of population growth in peri-urban areas and climate change. In response, there have been moves to increase fuel reduction—clearing, prescribed burning, biomass removal and grazing—to afford greater protection to peri-urban communities in fire-prone regions. But how effective are these measures? Severe wildfires in southern Australia in 2009 presented a rare opportunity to address this question empirically. We predicted that modifying several fuels could theoretically reduce house loss by 76%–97%, which would translate to considerably fewer wildfire-related deaths. However, maximum levels of fuel reduction are unlikely to be feasible at every house for logistical and environmental reasons. Significant fuel variables in a logistic regression model we selected to predict house loss were (in order of decreasing effect): (1) the cover of trees and shrubs within 40 m of houses, (2) whether trees and shrubs within 40 m of houses was predominantly remnant or planted, (3) the upwind distance from houses to groups of trees or shrubs, (4) the upwind distance from houses to public forested land (irrespective of whether it was managed for nature conservation or logging), (5) the upwind distance from houses to prescribed burning within 5 years, and (6) the number of buildings or structures within 40 m of houses. All fuel treatments were more effective if undertaken closer to houses. For example, 15% fewer houses were destroyed if prescribed burning occurred at the observed minimum distance from houses (0.5 km) rather than the observed mean distance from houses (8.5 km). Our results imply that a shift in emphasis away from broad-scale fuel-reduction to intensive fuel treatments close to property will more effectively mitigate impacts from wildfires on peri-urban communities.

Land management practices associated with house loss in wildfires

Losses to life and property from unplanned fires (wildfires) are forecast to increase because of population growth in peri-urban areas and climate change. In response, there have been moves to increase fuel reduction--clearing, prescribed burning, biomass removal and grazing--to afford greater protection to peri-urban communities in fire-prone regions. But how effective are these measures? Severe wildfires in southern Australia in 2009 presented a rare opportunity to address this question empirically. We predicted that modifying several fuels could theoretically reduce house loss by 76%-97%, which would translate to considerably fewer wildfire-related deaths. However, maximum levels of fuel reduction are unlikely to be feasible at every house for logistical and environmental reasons. Significant fuel variables in a logistic regression model we selected to predict house loss were (in order of decreasing effect): (1) the cover of trees and shrubs within 40 m of houses, (2) whether trees and shrubs within 40 m of houses was predominantly remnant or planted, (3) the upwind distance from houses to groups of trees or shrubs, (4) the upwind distance from houses to public forested land (irrespective of whether it was managed for nature conservation or logging), (5) the upwind distance from houses to prescribed burning within 5 years, and (6) the number of buildings or structures within 40 m of houses. All fuel treatments were more effective if undertaken closer to houses. For example, 15% fewer houses were destroyed if prescribed burning occurred at the observed minimum distance from houses (0.5 km) rather than the observed mean distance from houses (8.5 km). Our results imply that a shift in emphasis away from broad-scale fuel-reduction to intensive fuel treatments close to property will more effectively mitigate impacts from wildfires on peri-urban communities.