Aim To quantify the impact of the 2019–2020 megafires on Australian plant diversity by assessing burnt area across 26,062 species ranges and the effects of fire history on recovery potential. Further, to exemplify a strategic approach to prioritizing plant species affected by fire for recovery actions and conservation planning at a national scale. Location Australia. Methods We combine data on geographic range, fire extent, response traits and fire history to assess the proportion of species ranges burnt in both the 2019–2020 fires and the past. Results Across Australia, suitable habitat for 69% of all plant species was burnt (17,197 species) by the 2019–2020 fires and herbarium specimens confirm the presence of 9,092 of these species across the fire extent since 1950. Burnt ranges include those of 587 plants listed as threatened under national legislation (44% of Australia's threatened plants). A total of 3,998 of the 17,197 fire‐affected species are known to resprout after fire, but at least 2,928 must complete their entire life cycle—from germinant to reproducing adult—prior to subsequent fires, as they are killed by fire. Data on previous fires show that, for 257 species, the historical intervals between fire events across their range are likely too short to allow regeneration. For a further 411 species, future fires during recovery will increase extinction risk as current populations are dominated by immature individuals. Main conclusion Many Australian plant species have strategies to persist under certain fire regimes, and will recover given time, suitable conditions and low exposure to threats. However, short fire intervals both before and after the 2019–2020 fire season pose a serious risk to the recovery of at least 595 species. Persistent knowledge gaps about species fire response and post‐fire population persistence threaten the effective long‐term management of Australian vegetation in an increasingly pyric world.

Dormancy and germination requirements determine the timing and magnitude of seedling emergence, with important consequences for seedling survival and growth. Physiological dormancy is the most widespread form of dormancy in flowering plants, yet the seed ecology of species with this dormancy type is poorly understood in fire-prone vegetation. The role of seasonal temperatures as germination cues in these habitats is often overlooked due to a focus on direct fire cues such as heat shock and smoke, and little is known about the combined effects of multiple fire-related cues and environmental cues as these are seldom assessed in combination. We aimed to improve understanding of the germination requirements of species with physiological dormancy in fire-prone floras by investigating germination responses across members of the Rutaceae from south eastern Australia. We used a fully factorial experimental design to quantify the individual and combined effects of heat shock, smoke and seasonal ambient temperatures on germination of freshly dispersed seeds of seven species of Boronia, a large and difficult-to-germinate genus. Germination syndromes were highly variable but correlated with broad patterns in seed morphology and phylogenetic relationships between species. Seasonal temperatures influenced the rate and/or magnitude of germination responses in six species, and interacted with fire cues in complex ways. The combined effects of heat shock and smoke ranged from neutral to additive, synergistic, unitive or negative and varied with species, seasonal temperatures and duration of incubation. These responses could not be reliably predicted from the effect of the application of single cues. Based on these findings, fire season and fire intensity are predicted to affect both the magnitude and timing of seedling emergence in wild populations of species with physiological dormancy, with important implications for current fire management practices and for population persistence under climate change.

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Risk-ranking protocols are used widely to classify the conservation status of the world's species. Here we report on the first empirical assessment of their reliability by using a retrospective study of 18 pairs of bird and mammal species (one species extinct and the other extant) with eight different assessors. The performance of individual assessors varied substantially, but performance was improved by incorporating uncertainty in parameter estimates and consensus among the assessors. When this was done, the ranks from the protocols were consistent with the extinction outcome in 70-80% of pairs and there were mismatches in only 10-20% of cases. This performance was similar to the subjective judgements of the assessors after they had estimated the range and population parameters required by the protocols, and better than any single parameter. When used to inform subjective judgement, the protocols therefore offer a means of reducing unpredictable biases that may be associated with expert input and have the advantage of making the logic behind assessments explicit. We conclude that the protocols are useful for forecasting extinctions, although they are prone to some errors that have implications for conservation. Some level of error is to be expected, however, given the influence of chance on extinction. The performance of risk assessment protocols may be improved by providing training in the application of the protocols, incorporating uncertainty in parameter estimates and using consensus among multiple assessors, including some who are experts in the application of the protocols. Continued testing and refinement of the protocols may help to provide better absolute estimates of risk, particularly by reevaluating how the protocols accommodate missing data.

We evaluated the restoration of native plant assemblages by topsoil translocation in the Hunter Valley, south-east Australia. Species' responses were characterized by defining nine plant functional types (PFTs) based on combinations of four response mechanisms (seed bank persistence, germination cues, resprouting mechanisms, and longevity) through which species were predicted to persist or decline following translocation. The effects of community type and delay in topsoil restoration on restoration outcomes were tested in an orthogonal experiment. Changes in species' frequency were detected using Bayesian statistics with prior probabilities derived from pre-clearing data. Few species failed to reestablish following translocation; these were offset by recruitment of other native species not detected prior to clearing. Compositional changes were more pronounced when topsoil was stockpiled (cf direct reinstatement), although there was no trend related to the period of stockpiling. The PFT response model correctly predicted the rank probability of decline in three of the nine PFTs, while a further three were correctly placed in the top ranks but in the incorrect order. Three PFTs were incorrectly ranked because the response model was incorrect. Resprouters declined more frequently than seeders; however, species with physical seed dormancy declined less frequently than those with either transient seed banks or physiological, morphological, or morpho-physiological dormancy, irrespective of resprouting ability. Species with short juvenile periods were more likely to increase. We conclude that PFTs based on fire-response traits represent a practical means of predicting species' responses to translocation and a basis for prioritizing species for supplementary planting.

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Aim: Existing abiotic and biotic threats to plant species (e.g., disease, drought, invasive species) affect their capacity to recover post-fire. We use a new, globally applicable framework to assess the vulnerability of 26,062 Australian plant species to a suite of active threats after the 2019-2020 fires.Location: Australia.

We applied an adaptive management approach to reduce extinction risks faced by a disjunct and ecologically significant population of Black Cypress Pine (Callitris endlicheri), listed as an endangered population on the New South Wales Threatened Species Conservation Act 1995. In summer 2001-2002, an unplanned fire burnt the population, resulting in mortality of most standing plants. Concerns were raised about the potential impact of herbivores, particularly feral Rusa Deer (Cervus timorensis), on the recruitment of post-fire seedlings that might replace the loss of fire-killed standing plants. We applied an adaptive management approach to detect trends in the population following the fire, and to evaluate and trial in situ management options for mitigating threats to the remaining plants. Post-fire monitoring detected continuing declines in both the remaining adult population and the post-fire cohort of seedlings, and identified browsing by Deer as a serious and ongoing threat to the population. We designed a controlled experiment, with the aid of natural and artificial 'nurse plants' to assess the effects of herbivore exclusion on seedling growth and survival, and to test for differences in those effects under alternative management strategies. The experiment was designed and implemented with little cost other than field time and with logistic constraints on replication. By protecting exposed seedlings from browsing using woody debris, we were able to significantly increase seedling growth and survival, and to quickly arrest the population decline. Our results suggest that excluding Deer from the population by more permanent means will have a significant positive effect on its long-term persistence. Our case study demonstrates the utility of adaptive management approaches in threatened species conservation, their feasibility even under severe budgetary and logistical constraints, and how ongoing monitoring and experimentation are crucial for successful management of biodiversity.