Acianthera alpestris

In the Blue Mountains much of the natural habitat within the elevation range of this species is secondary forest, reflecting a long history of clearance for small scale shifting agriculture and coffee plantations, alongside large-scale planting of Caribbean pine. While commercial forestry has largely ceased since the 1980s due to the effects of Hurricane Gilbert, forest loss and fragmentation associated with subsistence farming and housing, shifting agriculture for cash crops, illegal selective logging, and coffee plantations continues, particularly in the lower elevation buffer zones of the National Park (Headley 2003, Chai et al. 2009). Continued road construction into the interior region of the Blue Mountains is likely to increase the rate of deforestation in previously inaccessible areas (Schipper 2024). Past clearance and subsequent regeneration of secondary forest has facilitated the spread of several invasive species in the Blue Mountains, including the Australian tree Pittosporum undulatum. The spread of P. undulatum accelerated after Hurricane Gilbert in 1988; it now comprises a dominant component of secondary forests in the Blue Mountains, and continues to invade longer-established forests. Long term monitoring indicates that an increase in the dominance of Pittosporum undulatum in forest plots is associated with a decrease in diversity and and richness of native tree species (Bellingham et al. 2018). The same study noted that epiphytes were absent from the trucks and branches of even large individuals of P. undulatum (Bellingham et al. 2018), indicating that this species may not act as a suitable host for A. alpestris, further decreasing the quality of habitat for this species. In the central highlands this species has only been collected from the Mount Diablo/Hollymount region, where illegal logging is likely the most significant threat to this species. Logging has contributed to degradation of montane forest at Mount Diablo, even within forest reserves. Removal of large trees is also likely to directly impact this species, which relies on these trees as hosts. Some agricultural activity has been observed in parts of the forest. Bauxite and limestone mining is prevalent in the central highlands but is not currently impacting any of the localities where this species has been collected.

All orchid species are included in Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This species occurs in the Blue and John Crow Mountains National Park. It is not held in any ex situ conservation collections (BGCI 2024), although it may be cultivated by some specialist orchid growers.