Dactylanthus with bat image credit David Mudge - Nga Manu Trust
Pua o te Rēinga/Dactylanthus taylorii is New Zealand’s only fully parasitic plant, and its elusive nature means its steady decline has gone unnoticed by many.
Next Tuesday, a group representing Wellington’s iwi, along with Council and ZEALANDIA staff, are heading to Pureora Forest Park to collect seed of pua o te Rēinga/dactylanthus for planting in Otari-Wilton’s Bush and ZEALANDIA Te Māra a Tāne.
Experts at Otari-Wilton’s Bush have been working to bring this special plant back to Wellington for about two years.
Otari is the only public botanic garden in New Zealand dedicated solely to native plants and this exciting project demonstrates the success they are having in the field of conservation research, says Mayor Andy Foster.
“We are very proud of the amazing work done by the team at Otari. Their threatened plant research programmes are contributing to the knowledge and conservation of endangered native species, which is invaluable and crucial in our commitment to biological diversity and preservation.”
Representatives of all six Greater Wellington region iwi will be attending the translocation of the seeds. This is the first time all iwi will be collaborating on a single translocation, says ZEALANDIA’s Bicultural Engagement Lead Ranger, Terese McLeod.
“Our work to return pua o te Rēinga is bringing about an historic first – where iwi across the Greater Wellington region; Rangitāne, Ngāti Kahungunu, Taranaki Whānui, Ngāti Toa Rangatira, Te Āti Awa ki Whakarongotai and Raukawa are collaborating collectively for the survival and advocacy of this rare and declining species.
”Pua o te Rēinga has a close relationship with pekapeka/short-tailed bats, however due to the decline of bats, predation from possums and human collectors the plant is in serious decline,” she adds.
Otari-Wilton’s Bush and ZEALANDIA provide habitat which have no or low mammalian predators which will help these populations to establish in Wellington. The plant plays an important role in native ecosystems and the nectar pua o te Rēinga produces is an important food source for bats and invertebrates.
“While ZEALANDIA will not be able to rely on bats for pollination, we will be able to explore the relationship this plant has with other native species. For example, it will likely be very appealing to the nectar-loving birds in the sanctuary, and we may even discover they have a role in pollination,” says Dr Danielle Shanahan, Director of ZEALANDIA’s Centre for People and Nature.
Wellington City Council’s Conservation and Science Advisor Karin van der Walt says that her team has been researching how the plant germinates, its seed characteristics and its dormancy patterns, all of which have helped them to better understand the plant.
“The translocation of dactylanthus into Wellington provides another important aspect to aid in its conservation while research into seed conservation continues. Germination efforts have been unsuccessful to date, but this has highlighted the importance of planting seed into the wild,” she says.
This project is supported by funding from Wellington Zoo’s Local Conservation Fund and Botanic Gardens Conservation International’s Global Botanic Garden Fund. It is being made possible by mana whenua from across the Wellington region, David Mudge from Ngā Manu Trust and also Pureora iwi and DOC staff.
Pua o te Rēinga is NZ’s only endemic (unique to NZ) fully parasitic plant and the southern-most member of its mainly tropical family. Dactylanthus is assumed to be extinct in the Wellington Region, the last known record is from the Akatarawa Forest in Upper Hutt in the 1940s. There are no records of it occurring in Wellington City, but as more than 95% of native forest has been cleared and the rest heavily impacted by grazing animals and pests, it is likely it was lost before it had been noticed here.
Some unique points to this plant:
- Gets all its energy through attaching itself to a host tree and taking energy from them, rather than photosynthesis (it has no green leaves). Scientists call these species holoparasites.
- When it attaches to the host tree, it causes the host root to flare (this helps the plant attach). This flared surface on the root was a prized collectable and people searching for these has led to its decline.
- Each plant can produce up to a cup of nectar when it flowers. This is a very important food source for short-tailed bats.
- This nectar (has evolved to smell super good to mammals as the bat used to be the only terrestrial mammal in NZ) has led to its decline through introduced mammals, especially possums.
From IUCN definitions:
Translocation - is the human-mediated movement of living organisms from one area with release in another.
Reintroduction - the intentional movement and release of an organism inside its indigenous range from which it has disappeared.
Assisted colonisation - the intentional movement and release of an organism outside its indigenous range to avoid extinction of the focal species.