Document ID: chunk:federal_register_of_legislation:F2025L00287:reg:3:p240
Version: federal_register_of_legislation:F2025L00287
Segment Type: reg
Provision Reference: reg 3 (pt 240/276)
Character Range: 878133–882480

Chimneys Reserve (497; Mills 2017g), Anson and Selwyn Reserves (333; Mills 2017d), Cascade Reserve (67; Mills 2017f), Ball Bay Reserve (64; Mills 2017b), Bumbora Reserve (31; Mills 2017a) and Hundred Acres Reserve (26; Mills 2017e).
The distribution is shown in Map 60.

Ecology
Little known.

Habitat
Occurs within coastal pine and white oak forest, coastal white oak shrubland and coastal grassland (Invasive Species Council & TierraMar 2021).

Threats
The primary threat to the species is weed invasion and competition, particularly by kikuyu (Cenchrus clandestinus).

Impact on other species
None known.
Map 60 Distribution of Senecio australis
Green outlines indicate reserves within which the species occurs. Green shading shows plant communities within which the species may occur (Christian & Mills 2021, Mills 2009a). Points show recorded locations (Mills 2009b, 2017a, b, d, e, f and g).

Risk assessment
Risk assessment undertaken for Vulnerable herbs/grasses as a grouping. The risk assessment is shown in Table 137.
Table 137 Risk assessment for Vulnerable herbs/grasses as a grouping
Risk                                                                                                               Likelihood of exposure    Consequence  Threat rating
1. Loss and fragmentation of native vegetation through past land clearing                                          Almost certain (91–100%)  Extreme      Extreme
2. Loss and fragmentation of native vegetation through current or future land clearing                             Rare (0–10%)              Negligible   Negligible
3. Degradation of native vegetation through past grazing or loss of nutrients                                      Almost certain (91–100%)  Extreme      Extreme
4. Degradation of native vegetation through current or future grazing                                              Possible (26–50%)         Moderate     Medium
6. Predation by rodents                                                                                            Rare (0–10%)              Negligible   Negligible
7. Predation by cats                                                                                               Rare (0–10%)              Negligible   Negligible
8. Predation or damage by chickens                                                                                 Rare (0–10%)              Negligible   Negligible
9. Predation by swamphens                                                                                          Rare (0–10%)              Negligible   Negligible
10. Predation by Argentine ant                                                                                     Rare (0–10%)              Negligible   Negligible
11. Competition from/change of habitat because of weed invasion                                                    Likely (51–90%)           Moderate     Medium
12. Infection by pathogens already present                                                                         Rare (0–10%)              Negligible   Negligible
13. Impacts of potential new invasive species or pathogens                                                         Unlikely (11–25%)         Minor        Low
14. Changes to vegetation, increased fire risk and/or direct physiological stress as a result of climatic changes  Possible (26–50%)         Moderate     Medium
15. Problems caused by small populations, including lack of genetic diversity                                      Possible (26–50%)         Moderate     Medium

Management actions
Undertake propagation and replanting into suitable habitat areas. Conduct targeted weed control and maintenance. Implement habitat protection and rehabilitation.

Recovery target
The recovery target is shown in Table 138.
Table 138 Recovery target for Senecio australis
EPBC Act status  Estimated population (2023)  Where known populations occur  2034 target
Vulnerable       1454                         34% within the national park   3000
                                              66% within public reserves

Relevant literature
Christian NE & Mills K (2021) Vegetation Mapping of Norfolk Island 2021. Unpublished data.
Invasive Species Council & TierraMar (2021) The Native Plant Communities of Norfolk Island. Invasive Species Council, Katoomba, NSW.
Mills K (2009a) The