Endangered Orchids on Cape Otway’s Dunes

The leafy greenhood orchid (Pterostylis cucullata) is an extraordinary colony forming plant. There are several populations around Victoria, occurring in both coastal and alpine habitats, although nowhere in between.

The species is listed as Endangered in Victoria under the Flora and Fauna Guarantee Act 1988, and Vulnerable nationally under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). There are actually two subspecies, Pterostylis cucullata subsp. cucullata that is found in Cape Otway, and Pterostylis cucullata subsp. sylvicola that is found in alpine regions

On Cape Otway, several greenhood colonies survive the exposed coastal conditions, but the species suffers adversely from intensive grazing, and changes to fire regimes leading to heightened competition with other native plants. We know that on Cape Otway we have lost several of our colonies in the past decades due to adverse land management.

In response, we established a program in 2016 to keep tabs on the condition of each of the known colonies and locate new plant locations in our region so that we are in the best position to conserve them into the future. Due to the comprehensive surveys across the Cape we now know of many more populations of greenhoods than previously.

While the discovery of these undocumented colonies was exciting, threatening processes are a real threat to this fragile plant and we still consider it to be at risk. In response, we have developed a long-term monitoring program observing the timing of flowering, density of plants and levels of herbivory damage and level of competition from shrubs to understand if they are causing the local extinctions. This information will help us learn how the species responds to management and a changing climate.