Document ID: chunk:federal_register_of_legislation:F2024L00270:body:0:p19
Version: federal_register_of_legislation:F2024L00270
Segment Type: other
Provision Reference: 
Character Range: 51809–54952

reconnect populations to avoid further erosion of genetic diversity and fitness decline (as has been documented for the lowland population).
The southern genetic group (Powelltown population) appears to be most vulnerable based on its size. It also was inferred to have had the most recent gene flow with extinct Bass River population, which in turn shared genes with the lowland population (Hansen et al. 2009). This suggests mixing lowland possums with those of the southern groups should replicate past gene flow and thus be of low risk of outbreeding depression.
Small and isolated subpopulations may be particularly at risk from genetic, stochastic and other factors: for example, even a relatively small bushfire may destroy all habitat in the Yellingbo area (Harley 2015a). PVA has indicated that discrete subpopulations need to be larger than a threshold of 200 individuals to have at least a 90% chance of persistence over a 100-year period (Lindenmayer and Lacy 1995b; Lindenmayer 2000).

Implications for conservation management
    * Populations in the highland tall forests and the lowland swamp forest must be maintained. Given the parlous status of the lowland subpopulation, there may be a need to enhance its genetic stock through careful gene-pool mixing (i.e., outbreeding with highland animals).
    * Management should aim to increase the population size and geographical extent of the lowland swamp forest subpopulation.
    * Management should seek to actively retain or enhance adequate habitat connectivity within the montane forest habitat through linking reserves and wildlife corridors and artificial connectivity over roads, or if necessary to augment such connectivity through careful translocation.

Priority research needs to enhance management
    * Use the results of monitoring of genetic diversity within highland subpopulations to (1) detect fragmentation and isolation effects and (2) inform appropriate ongoing management strategies that maintain genetic diversity. Greater sampling across highland populations is required, including:
          increasing the number of samples across some previously under-sampled locations (those fewer than 10 samples), and
          obtaining samples from some localities with occupied lowland habitat within the highland range.
    * Assess the risks, costs and benefits, and likelihood of success of options for genetic rescue of the lowland swamp forest subpopulation, including gene pool mixing between the lowland swamp forest subpopulation and other subpopulations.
    * Validate harmful and climate-adaptive genetic variants as predictors of individual fitness in the inbred lowland populations using genomic data. This will allow targeting best quality individuals for genetic rescue and population management.
    * Collect and biobank sperm and somatic tissues from at risk populations (for example, lowland) for restoring genetic diversity in the future.

3.4                 Habitat

3.4.1             Key habitat features
Broadly, the key habitat features required by Leadbeater's possum are (1) suitable (large) hollows for denning and breeding, at a