Document ID: chunk:federal_register_of_legislation:F2025L00287:reg:3:p223
Version: federal_register_of_legislation:F2025L00287
Segment Type: reg
Provision Reference: reg 3 (pt 223/276)
Character Range: 818617–822703

the 1830s (Sykes & Atkinson 1988). A survey in 1989 failed to locate additional individuals again, confirming that this species was very rare in the national park (Gilmour & Helman 1989b). There were only five mature, seed-producing individuals of Myoporum obscurum remaining until replanting began in 1995.
Mills (2012b) found the species during surveys within the park at four sites where six plants were counted. No seedlings were found and only two wild trees were found at two of the sites surveyed. The species has been planted along the tracks in the national park and in gardens on Norfolk Island. The species was recorded within several reserves in 2017 (mostly plantings), including Selwyn, Cascade and Two Chimneys Reserves (Mills 2017d, f, g).
The population had increased to 417 individuals in 2021. Propagation and planting have occurred through the Norfolk Island National Park threatened flora program.
The distribution is shown in Map 50.

Ecology
Little known.

Habitat
This species prefers clearings, canopy gaps or open areas away from the coast (Sykes & Atkinson 1988).

Threats
Threats to the species include weed invasion and competition, and small population size and subsequent increased risk of extinction through natural events such as cyclones, slips and drought. Phytophthora cinnamomi is potentially a major risk.
Map 50 Distribution of Myoporum obscurum
Green outlines indicate reserves within which the species occurs. Points show recorded locations (Mills 2017a, d, e, f, g).

Impact on other species
None known.

Risk assessment
Risk assessment undertaken for Critically Endangered trees/shrubs as a grouping. The risk assessment is shown in Table 117.
Table 117 Risk assessment for Critically Endangered trees/shrubs 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                                                                                            Unlikely (11–25%)         Minor        Low
7. Predation by cats                                                                                               Rare (0–10%)              Negligible   Negligible
8. Predation or damage by chickens                                                                                 Likely (51–90%)           Moderate     Medium
9. Predation by swamphens                                                                                          Rare (0–10%)              Negligible   Negligible
10. Predation by Argentine ant                                                                                     Possible (26–50%)         Minor        Low
11. Competition from/change of habitat because of weed invasion                                                    Likely (51–90%)           Major        High
12. Infection by pathogens already present                                                                         Possible (26–50%)         Moderate     Medium
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