Justification
Chiloglottis anaticeps is known from three subpopulations in NSW, Australia. The main factor that makes the species eligible for listing in the Endangered category is its restricted distribution, restricted number of locations and inferred continuing decline in quality of habitat due to disturbance by feral pigs (Sus domesticus), impacts from recreational and infrastructure maintenance activities, and projected declines from high severity future bushfire events.
Geographic Range Information
The Duck’s-head Wasp-orchid is known from three subpopulations at Barokee (Cathedral Rock National Park), Mooraback (Werrikimbe National Park) and Hastings Forest Way (Werrikimbe National Park) in New South Wales (NSW). All subpopulations occur at high elevation (800–1,400 m above sea level).
Population Information
There are likely to be approximately 100,000 known plants across the three subpopulations. Given the species can reproduce clonally (Phillips pers. comm. 3 June 2021), the number of distinct individuals (effective population size) is likely to be substantially less than 100,000, possibly around 20 per cent of the apparent number of plants (Chung et al. 2004).
Habitat and Ecology Information
Relevant biology and ecology
Reproductive ecology
Flowering occurs from December to March and flowers may last for days or weeks until pollinated, after which they rapidly senesce (Jones 2021). As flowering material is required for identification, surveys must be undertaken during this period. The Duck’s-head Wasp-orchid has a very specialised pollination strategy, with pollination only carried out by sexual deception of male Neozeleboria sp. 33 (a thynnine wasp), which are likely attracted to the flowers by chemical and visual stimuli (Peakall et al. 2010). Once attracted, the male wasp attempts to copulate with the labellum, mistaking it for the female wasp, removing or depositing pollinia in the process, which effects pollination. Fruits take approximately one month to mature following pollination. Each mature capsule contains hundreds of minute seeds that are dispersed by wind when the capsule dehisces. After fruits have ripened, the plant dies back to its dormant subterranean tubers. Plants reproduce from seed and clonally, with each tuber living for one year and producing two to three tubers during that time (Jones 2021). Seed germination requires infection by mycorrhizal fungi from the genus Tulasnella (Roche et al. 2010). No data are available regarding the generation length or plant longevity for the Duck’s-head Wasp-orchid. However, as the species is capable of reproducing clonally, colonies are expected to have a very long lifespan. The length of the juvenile period is several years for most terrestrial orchids in cultivation (Freestone pers. comm. 30 June 2021).
Habitat ecology
At Mooraback, the Duck’s-head Wasp-orchid grows on a steep slope in clay loam over basalt, in montane wet sclerophyll forest with Eucalyptus radiata (Narrow-leaf Peppermint), E. viminalis (Manna Gum), E. pauciflora (Snow Gum), E. campanulata (New England Blackbutt), E. nobilis (Giant White Gum), Leucopogon affinis (Lance Beard-heath), Lomatia silaifolia (Crinkle Bush), Podolobium ilicifolium (Prickly Podolobium), Lomandra longifolia (Spiny-headed Mat-rush) and Poa sieberiana (Grey Tussock-grass). The Hastings Forest Way subpopulation occurs in similar vegetation to Mooraback, although the site is flatter. At Cathedral Rock, it grows on a flat site in coarse sandy soil over granite in E. acaciiformis (Wattle-leaved Peppermint) forest with Banksia integrifolia (coast banksia) and Grey Tussock-grass (ALA 2021; Copeland pers. comm. 2 June 2021).
Fire ecology
All subpopulations were burnt at low severity during the 2019–20 bushfires (canopy and understorey trees mostly remaining unburnt) and all subpopulations exhibited a very strong post-fire flowering response 14 months post-fire (January 2021) (Phillips pers. comm. 3 June 2021). Flowering was more prolific than in previous years. However, the response of this species to more intense or frequent fires, or those occurring at other times of the year (e.g. planned burns) is unknown, but fires during the active growth and flowering stages are likely to be deleterious. Fires may also affect thynnine wasp pollinator communities (Brown et al. 2017) on which the orchid is dependent for pollination.
Habitat critical to the survival
The Duck’s-head Wasp-orchid occurs in montane tall eucalypt forest with a sparse or grassy understorey, in clay loam over basalt or sandy loam over granite. Habitat critical to the survival of the species comprises the entire area of occupancy of known subpopulations, as well as areas of similar habitat surrounding known subpopulations and additional occurrences of similar habitat that may contain important subpopulations of the species.
Threats Information
The main threats to the Duck’s-head Wasp-orchid currently are invasive pests, habitat degradation and climate change.
Use and Trade Information
Indigenous Australians have a long history of management of the country on which the Duck’s-head Wasp-orchid occurs. The species currently occurs on country of the Armidale and Kemspey Aboriginal Land Councils in New South Wales (New South Wales Aboriginal Land Council 2021). Although little is known of the cultural significance of Duck’s-head Wasp-orchid, other orchid species are culturally significant plants for Indigenous peoples, with their tubers used as a food source (Australian National Botanic Gardens 2007).
Conservation Actions Information
Conservation and management priorities
Habitat loss disturbance and modifications- Ensure locations of populations are kept updated on state databases used by fire, road and land management agencies. Where appropriate, implement measures to reduce the risk of disturbance from trail management and maintenance works.
- Implement measures to reduce trampling and impacts from recreational activities where appropriate, such as fencing and signage.
- Determine potential habitat for the species in the NSW forestry estate. Forestry: undertake pre-harvest surveys in areas of suitable habitat that are designated for harvesting and implement 100 m buffer exclusion zones from any forestry activity around all subpopulations.
Climate change and fire- Develop a fire management plan to ensure that fire regimes occurring at the sites are consistent with population persistence of the species.
- Ensure fire management authorities are supplied with updated maps of species occurrence and that fire suppression and mop up operations avoid known populations.
- Avoid out of season planned fires from November to March.
- Avoid small fires that may concentrate post-fire herbivory on subpopulations.
- Identify and protect current and future habitat likely to remain or become suitable habitat due to climate change.
Invasive species (including threats from grazing, trampling, predation)- Continue ongoing feral pig control near all subpopulations.
- If necessary, protect subpopulations from browsing by feral pigs (e.g. by fencing).
Ex situ recovery actions- Collect and maintain seed seed collections and fungal symbionts for ex situ seed banking, as per the Plant Germplasm Conservation Guidelines (Martyn Yenson et al. 2021).
- Undertake ex situ propagation and, where appropriate, translocation trials in accordance with the Guidelines for the Translocation of Threatened Plants in Australia (Commander et al. 2018). However, due to the large area of apparently suitable habitat, further surveys remain the priority for this species.
- Where translocation is undertaken, monitor all translocated individuals to maturity, seed set and recruitment to ensure they are viable and are contributing to a reduction in the extinction risk for the species.
Stakeholder engagement/community engagement- Engage and involve Traditional Owners in conservation actions, including surveying for new populations and management actions.
- Liaise with the local community and government agencies to ensure that up-to-date population data and scientific knowledge inform the implementation of conservation actions for this species.
- Engage community groups by encouraging participation in surveys or monitoring for the species.
- Inform managers of sites where there are known populations and consult with these groups regarding options for conservation management and protection of the species.
Survey and monitoring priorities- Conduct targeted surveys throughout the range of the Duck’s-head Wasp-orchid to better determine its population size. Surveys should be undertaken when the species is flowering from December to March.
- Improve understanding of the pollinator, its life cycle and ecology (and that of its prey species), and its response to fire seasonality, frequency and severity.
- Improve understanding of the orchid's life history, including tuber dynamics, leaf dynamics and seedling recruitment including the microbial symbionts involved in germination.
- Improve understanding of the sensitivities of the Duck’s-head Wasp-orchid to fire seasonality, frequency and severity.
- Maintain a monitoring programme to: record response to future bushfires; determine trends in population size and distribution; determine threats and their impacts; and monitor the effectiveness of management actions and the need to adapt them if necessary.
Information and research priorities- Increase survey effort to locate additional subpopulations.
- Investigate the population genetics of known subpopulations, particularly the number of genetically distinct individuals in subpopulations expected to contain a large proportion of clones.
- Identify the time of year plants are dormant, and the timing of leaf emergence.
- Investigate the biology and ecological requirements of the pollinator.
- Investigate recruitment, seedling survival and plant longevity/generation length.
- Identify fire regimes that are detrimental and those that allow population persistence.