Document ID: chunk:federal_register_of_legislation:F2025L00287:reg:3:p189
Version: federal_register_of_legislation:F2025L00287
Segment Type: reg
Provision Reference: reg 3 (pt 189/276)
Character Range: 698367–702357

Conservation Act 2016 (NSW)
For further information on the species outside of the Norfolk Island Group, see the species profile on SPRAT.

Description
A thin stemmed climbing or creeping vine with sparse leaves.

Distribution and abundance
On Norfolk Island, 95% of the natural population of Calystegia affinis is found in the open higher parts of Mt Pitt and Mt Bates, though it occasionally comes up from dormant seed when forest or scrub is cleared (Sykes & Atkinson 1988). In 2003 the Norfolk Island population consisted of about 45 mature individuals (TSSC 2003a). In 2012, 13 plants were counted across five transects (Mills 2012b). The plants were all on the higher parts of Mount Pitt and Mount Bates, except for one plant near the Red Stone Link Track. The population estimate in 2021 was 28 individuals.
C. affinis is also found on Lord Howe Island but it is very rare, known from only four locations with possibly only one plant at each location, sprawling over an area of some square metres.
The distribution within the Norfolk Island Group is shown in Map 29.

Ecology
Stems take root when touching the soil. The species grows prolifically in the sun under cultivation.

Habitat
Found on the open higher parts of mountain tops on Norfolk and Lord Howe Islands.

Threats
The primary threats to the species are weed invasion and competition, and habitat clearing and modification through track maintenance.

Impacts on Other Species
Can climb vigorously over other plants in cultivation.
Map 29 Distribution of Calystegia affinis
Green outlines indicate reserves within which the species occurs.

Risk assessment
Risk assessment undertaken for Critically Endangered vines/climbers as a grouping. The risk assessment is shown in Table 75.
Table 75 Risk assessment for Critically Endangered vines/climbers 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                                                                                            Almost certain (91–100%)  Major        Extreme
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                                                    Almost certain (91–100%)  Major        Extreme
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