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Context: Obligate-seeding woody plants with long reproductive maturity periods and no soil seed banks are threatened with decline as climate change drives more frequent and severe fires, such as the extensive 2019–2020 wildfires in south-eastern Australia. Aims: This study aimed to investigate the effects of fire intervals and severity on the persistence of one such species, Banksia cunninghamii (Hairpin Banksia), in temperate forests. Methods: We measured post-fire seedling recruitment of B. cunninghamii at 25 sites in Victoria, burned at various severities in the 2019–2020 wildfires and with differing prior fire intervals. A Bayesian framework was used to model the relationship between seedling numbers, fire severity and fire interval. A spatial analysis compared a species distribution model for B. cunninghamii with fire severity and fire intervals. Key results: There was a low chance of B. cunninghamii recruitment (<25%) at sites that either had burned eucalypt canopies or a preceding fire interval of less than 12 years. Sixty-seven percent of its distribution in the south-east of the state of Victoria was mapped as burned at high severity (burned eucalypt canopies) between 1998 and 2020, or burned at shorter than 12 year intervals between 1960 and 2020, although some B. cunninghamii populations will have persisted due to the patchiness of past burns. Conclusions: Banksia cunninghamii is vulnerable to local extinctions in the wildfire-affected areas if fires occur again before plants reach maturity, or if high fire severity destroys seeds. Implications: More frequent and severe wildfires mean that burn planning needs to consider the reproductive cycles of serotinous obligate-seeding plants. Populations of Banksia cunninghamii are declining as climate change drives more frequent, severe and widespread fires. Research on this species after south-eastern Australia's 2019–2020 wildfires found that plants are killed by fire, with a low chance of seedling regeneration where severe fires burned eucalypt canopies, or the previous fire was less than 12 years ago. Large areas are no longer likely to support Banksia cunninghamii , and management is needed to protect juvenile plants until they produce seed cones. Photograph by Annette Muir. [ABSTRACT FROM AUTHOR]

• Arboreal camera trapping used to assess post-fire occurrence of Leadbeater's possum. • Unburnt refugia in local landscape positively influences post-fire occupancy. • Sites with higher pre-fire disturbance had higher Leadbeater's possum occupancy. • Proximity to unburnt habitat outside the fire perimeter did not influence occupancy. • Population recovery likely driven by in situ survival rather than recolonisation. Large wildfires have the potential to create heterogeneous landscapes in forest ecosystems. Range-restricted species in fire-prone regions have evolved to persist in the face of periodic disturbance due to wildfire. However, the factors that enable them to do so are often poorly understood. Whether post-fire population recovery is driven by survival of individuals within the burnt area (in situ recovery) or by recolonisation from unburnt habitat outside the fire perimeter (ex situ recovery), and over what timeframe this occurs, is valuable knowledge for conservation management. Understanding post-fire population dynamics is important when considering whether management interventions are required to prevent local extinctions. We examined the influence of fire-derived landscape context on site occupancy by the critically endangered Leadbeater's possum Gymnobelideus leadbeateri in south-eastern Australia, 6–11 years after a large wildfire in 2009. Our aim was to assess whether site occupancy was influenced by fire extent in the local landscape, distance from unburnt habitat outside the fire perimeter, and/or pre-fire disturbance history. We used arboreal camera trapping to survey Leadbeater's possums within the burnt area, using 732 cameras at 245 sites. We used occupancy modelling to estimate the effects on site occupancy of (1) unburnt habitat surrounding sites (500 m radius), (2) distance from unburnt habitat at the fire perimeter, and (3) whether the site had been disturbed by either fire or timber harvesting in the decades prior to the 2009 fire. Leadbeater's possums were detected at 78 of the 245 sites (32 %). Site occupancy was positively influenced by the presence of unburnt habitat within 500 m, and was higher at sites that had experienced disturbance between the 2009 fire and the previous major wildfire in 1939. Proximity to unburnt habitat outside the fire perimeter did not influence occupancy. Our results suggest that population recovery was driven primarily by in situ survival and recovery, rather than via recolonisation from source populations outside the burnt area. Our findings indicate that Leadbeater's possum populations are more likely to recover from fires that are more heterogeneous in their severity, leaving relatively more unburnt patches within their perimeter. Post-fire management interventions such as translocation to facilitate population recovery are likely unnecessary for this species, provided surviving individuals have spatial continuity of habitat to enable recolonisation. Management strategies aimed at the retention of unburnt patches within the footprint of future fires will likely promote the post-fire recovery of arboreal mammal species in fire-prone forests, particularly under a changing climate with increased frequency and intensity of wildfires. [ABSTRACT FROM AUTHOR]

Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua) between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007–2011). Fish were tagged and released in autumn 2007–2009 in the mid-Murray (n = 42) and lower Goulburn (n = 37) rivers within 3–6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem–tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem–tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers. [ABSTRACT FROM AUTHOR]

Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua) between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007–2011). Fish were tagged and released in autumn 2007–2009 in the mid-Murray (n = 42) and lower Goulburn (n = 37) rivers within 3–6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem–tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem–tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers. [ABSTRACT FROM AUTHOR]