Document ID: chunk:federal_register_of_legislation:F2024L00346:reg:4:p4
Version: federal_register_of_legislation:F2024L00346
Segment Type: reg
Provision Reference: reg 4 (pt 4/7)
Character Range: 61030–64184

Spiny Rice-flower.
Climate change can also drive changes in existing fire regimes, with more frequent and intense fires projected alongside shorter windows of opportunity for individuals to reach maturity before fire recurs (immaturity risk; Westerling et al. 2011). Given that fire severity and frequency are both predicted to continue to increase under climate change (van Oldenborgh et al. 2020), some species may be driven to extinction in coming decades as fire-free periods are reduced (Enright et al. 2015). This has potential ramifications for communities that are adapted to and shaped by fire events including grasslands of the Victoria Volcanic Plain, and species associated with them, including Spiny Rice-flower.

Fire regimes that cause declines in biodiversity
Grassland communities require regular biomass reduction to maintain their habitat structure and species richness (Morgan 1995; DAWE 2022). Historically, biomass reduction has been facilitated by natural fire and low intensity grazing from native herbivores (Lunt & Morgan 1999 cited in DSE 2008). Fire regimes that cause biodiversity decline in temperate grassland communities on the Victoria Volcanic Plain, where the Spiny Rice-flower predominantly occurs, have been identified as low fire frequency and fire-competition interaction (DAWE 2022). Low fire frequency (long intervals between fires) cause decline in these populations directly by failing to trigger essential life-history cues to habitat suitability, or through interactions with other threats such as fragmentation (DEWHA 2009; TSSC 2016; DAWE 2022). Traits sensitive to low fire frequency include a combination of short-lived seed banks and low seed-dispersal range (DAWE 2022); these traits are possessed by Spiny Rice-flower (Foreman 2005, 2011; Reynolds 2013; James & Jordan 2014; TSSC 2016). For natural temperate grassland communities, fire-competition interactions may pose a threat when fire accelerates invasion processes by creating gaps for the entry of invasive competitor or when it promotes the establishment of high-density dominant native species that outcompete other native inhabitants and eventually transform the characterising structure and composition of the communities (DAWE 2022). Too frequent fire may threaten invertebrate populations including those that pollinate Spiny Rice-flower.
For Spiny Rice-flower and many grassland species, fire can support their persistence. Reducing biomass through planned burning promotes germination and seedling establishment of Spiny Rice-flower, although it can also lead to increased mortality of existing plants or removal of reproductive output (soil seed bank) if it is undertaken during flowering seasons (Regan et al. 2021).

Weeds
The invasion of exotic plants which leads to habitat degradation and competitive exclusion Spiny Rice-flower is one of the key threats observed across sites. The risk is greatest in the smaller, more isolated and heavily disturbed sites where populations will almost certainly be lost without active weed and biomass management (Foreman 2012).
In the absence of biomass reduction, the dominant perennial tussock