Caladenia brownii

Native vegetation of the region has been severely fragmented and degraded by clearance. The main ongoing threats to Caladenia spp. are further habitat degradation, fragmentation and loss of remnants and weed infestation (e.g., pasture grasses). Other threats to these terrestrial orchids include the spread of Phytophthora cinnamoni and Phytophthora cryptogea; grazing, most notably by kangaroos (Macropus fuliginosus) but also rabbit and stock and potentially insects. Digging by small mammals including rabbits and Quendas (Isoodon obesulus) are a potential threat as they dig burrows or seek orchid tubers as a food source; prescribed burning undertaken when the orchid is most vulnerable (between April to early November); and accidental damage from firebreak maintenance and other infrastructure maintenance may also affect this species. Recreational impacts such as trampling, picking of orchid flowers, soil compaction, rubbish dumping and habitat fragmentation by establishment of paths by visitors may exert further pressure on populations. Threats to roadside subpopulations include grading, chemical spraying, construction of drainage channels and the mowing of roadside vegetation.

Poor recruitment threatens other Caladenia spp. of the region with few plants developing seed without artificial assistance. It is suspected that low orchid recruitment rates from seed dispersed in their natural environment may in part be due to the patchy distribution of mycorrhiza. Natural recruitment of terrestrial orchids may only occur in years when a longer growing season results from above average spring rainfall prior to the onset of summer dormancy. Climatic conditions during this time are more conducive to the formation of tubers.

Although C. brownii is an attractive spider orchid, it does not appear to be sold commercially. The impacts of potential illegal collection for the horticultural trade, on the population of this species are unknown.

This species has been collected within numerous National Parks and Reserves throughout its range, where habitats conservation measures are in place. However, habitats do not benefit from protection across the entire range. In some conservation units (e.g., Leeuwin-NaturalisteNational Park) recovery Plans for some threatened Caladenia spp. which have the same distribution are also in place. They include for instance fencing against grazing, deep-ripping, rubbish removal, spot spraying of weeds and development of suitable fire management strategy.

The taxon is grown in various botanical institutions and by hobbyists. It is currently listed on Appendix II of the Convention on International Trade in Endangered Species (CITES). The taxon is considered not threatened in Western Australia (FloraBase, accessed on the 27th of July 2009). As with all orchids, the taxon should not be removed from the wild. The population should be monitored at regular intervals to detect any change in dynamics.