Orchids with scarce occurrence records: The case of the endangered Botany Bay Bearded Greenhood

Abstract

Poorly studied species are potentially under-prioritised by conservation programmes due to knowledge gaps presenting barriers to informing effective management strategies. The Botany Bay Bearded Greenhood, Pterostylis sp. Botany Bay, is an example of a poorly studied plant that is listed as endangered under both Commonwealth and New South Wales legislation. This study reports on archival surveys from 1998 to 2005 conducted at up to eight sites known to contain the Botany Bay Bearded Greenhood and follow-up surveys in 2022. The archival surveys found that the total population count ranged from 83 to 341 individuals. Mean numbers (± standard error) of seedlings, flowering individuals and individuals exhibiting capsule development recorded in the population were 43 ± 14, 33 ± 9 and 2 ± 1 respectively. The 2022 surveys did not detect the species. An area of potential habitat was derived from records in biodiversity databases, which determined a total historical extent of 1.38 ha restricted to the Kurnell Peninsula in Sydney, New South Wales. The priority next step is to gather contemporary data to confirm whether the Botany Bay Bearded Greenhood remains extant, which can be done by applied researchers, students, landholders and land managers, botanical practitioners and/or volunteers. For optimal species detection, we recommend undertaking formal surveys or opportunistic searches in historically known sites and replicating detection efforts across July–September periods to exploit seasonal flowering.