Document ID: chunk:federal_register_of_legislation:F2025L00287:reg:3:p209
Version: federal_register_of_legislation:F2025L00287
Segment Type: reg
Provision Reference: reg 3 (pt 209/276)
Character Range: 768616–772806

for Norfolk Island Flora - 15 Vulnerable Species.

Ileostylus micranthus—mistletoe
Family LORANTHACEAE

Conservation significance
Ileostylus micranthus is best known from New Zealand and was first collected on Norfolk Island in the 1930s. It is presumed to be a recent arrival on Norfolk Island as previous collectors had failed to find it (Orchard 1994).
EPBC Act Listing Status: Vulnerable.

Description
A bushy epiphytic mistletoe with green flowers and yellow fruit.

Distribution and abundance
I. micranthus has been reported from the upper slopes of Mt Pitt and the track leading to Red Road on Mt Bates (Orchard 1994) above the 200-metre contour. On Norfolk Island the number of mature individuals was fewer than 500 in 2003 (TSSC 2003b).
The distribution is shown in Map 41.

Ecology
An epiphytic parasite with a wide range of host plants.

Habitat
Occurs scattered on several host species within the national park, favouring Coprosma pilosa as its host.

Threats
The species is threatened by weed invasion, catastrophic events (such as severe storms), and limited distribution of its host C. pilosa.

Impact on other species
Parasitic on host species and heavy infestations on C. pilosa can kill the host plant.
Map 41 Distribution of Ileostylus micranthus
Green outlines indicate reserves within which the species occurs.

Risk assessment
The risk assessment is shown in Table 99.
Table 99 Risk assessment for Ileostylus micranthus
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                                                                                 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                                                    Unlikely (11–25%)         Moderate     Low
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  Unlikely (11–25%)         Minor        Low
15. Problems caused by small populations, including lack of genetic diversity                                      Possible (26–50%)         Major        High

Management actions
Undertake revegetation/habitat restoration. Undertake targeted weed control and maintenance.

Recovery target
The recovery target is shown in Table 100.
Table 100 Recovery target for Ileostylus micranthus
EPBC Act status  Estimated population (2023)  Where known populations occur  2034 target