Category: Nature NSW

Berin Mackenzie, Scientist (Ecosystems and Threatened Species), NSW Department of Planning, Industry and Environment (DPIE)

Nearly two decades in the making, the translocation of Wollemi Pine into Wollemi National Park has been a massive and highly successful interagency effort exemplifying the power of collaboration.

The imperative to translocate

The Wollemi Pine (Wollemia nobilis) was thought to have gone extinct over two million years ago until the remarkable discovery of a small relict population in a remote canyon system within Wollemi National Park in 1994. Fewer than 100 individuals of this critically endangered conifer remain in the wild and the risk of losing the entire population to a catastrophic event, such as a disease outbreak or severe wildfire, is high. Currently, the only viable conservation strategy to reduce this risk is to use translocation to increase the population size and geographic distribution by creating additional wild populations at a distance from the original stands. Following a successful pilot translocation in the Blue Mountains in 2012, increasing threats to the wild stands have created the imperative to undertake translocation into Wollemi National Park.

Project partners

The translocation program is an initiative of the Wollemi Pine Recovery Team – an expert panel of NSW government scientists and conservation managers tasked with safeguarding the species in the wild and understanding its ecology. Partners in the translocation project include scientists and threatened species officers from the Department of Planning Industry and Environment, the NSW National Parks and Wildlife Service (including Park Air), the Royal Botanic Gardens (Mount Annan, Mount Tomah and Sydney), and a number of external consultants and service providers. The translocation project is part of the broader Wollemi Pine conservation program funded under the NSW Saving Our Species program. This year, the team have been further aided by a prestigious National Geographic Society (NGS) Species Recovery grant to support the 2021 plant out and early monitoring. The Species Recovery grant is a partnership between the IUCN Species Survival Commission and NGS to assist on-ground priorities and conservation actions for threatened species worldwide, and the Wollemi Pine translocation is one of the first Australian projects to be selected for funding under the scheme.

Implementation

The spectacularly rugged terrain of Wollemi National Park and the complexity of the project have made this one of the most physically and logistically challenging plant translocations undertaken anywhere in the world. It has set the benchmark for threatened plant translocation in Australia and its successful implementation has required a diverse team of over 60 people. The requisite skillsets and expertise span plant ecology, experimental design and analysis, environmental survey, plant pathology, population genomics, horticulture, reserve and fire management, specialist helicopter operations, and a high level of physical fortitude and wilderness skills for the remote-area ground teams tasked with site surveys and establishing the experimental populations.

Throughout every stage of the project, the team have followed best practice guidelines and taken every practical measure to protect the sites from adverse impacts. This includes surveys for rare and threatened species and cultural heritage values; adherence to strict hygiene protocols and site confidentiality agreements; and adoption of leave-no-trace wilderness principles, requiring team members to sleep in hammocks to protect fragile understorey vegetation, to forego open fires despite near-freezing temperatures in the canyons, and to carry out all their personal waste.

In May 2019, after a two-year effort to identify suitable candidate sites, the first Wollemi Pine saplings were translocated into Wollemi National Park. Ground teams were inserted by helicopter and spent 16 days planting 436 saplings across two remote gorges, plus a further 22 days from June to August 2019 hauling over 3,500 litres of water up the canyons and cliffs to nurse the saplings through a severe drought. This backbreaking work was soon followed by heartache as the Black Summer bushfires impacted both sites in late 2019, before the young trees had time to establish or develop fire-resistance. Fifty-six saplings (26%) survived at one site and only four (2%) survived at the other. With much of their hard work up in smoke, the team began once more, propagating over 500 new saplings and spending a further 20 days out in the canyons to replant the sites in April and May this year.

Scientific foundations

Much has been learnt about the ecology of the Wollemi Pine since its discovery but a number of key knowledge gaps persist. For example, despite almost 30 years of monitoring we are yet to observe a single wild seedling or juvenile transition into an adult tree; hence, the best locations to plant saplings within the canyons to ensure their success remain unknown. Wild individuals only mature and produce cones once they reach the rainforest canopy and gain access to the sunlight above. Light and soil moisture are important for growth of young trees; however, the brightest planting locations are often more exposed to frequent fire and drought, and moister locations tend to have lower light availability. Hence, different locations involve trade-offs between short- and long-term benefits and risks, and sites that promote early survival and growth of Wollemi Pine may not be suitable for long-term persistence.

A powerful scientific framework known as ‘adaptive management’ is being applied to address uncertainty around the optimal planting strategy and to maximise learning opportunities. The efficacy of alternative planting strategies is being evaluated through a series of comparative ecological experiments with saplings positioned along natural environmental gradients from moist rainforest in the depths of the canyons to Eucalypt-dominated rocky ledges above. How variation in light, soil moisture and flammability/fire risk affects growth, maturation and survival will be assessed over different timescales with direct benefits for ongoing conservation management of both the wild and translocated populations.

Laying the groundwork for future generations

The long-term goal of the project is the creation of self-sustaining populations and an early indication of success will be the appearance of second-generation seedlings (‘grandchildren’). It would be incredibly rewarding for the team to see this goal realised; however, given the slow growth and maturation of Wollemi Pine in the wild, it could take many decades or longer – likely beyond our lifetimes. Hence, it will take an intergenerational effort with future generations of scientists and environmental stewards bringing this work to fruition. It’s a really beautiful dimension to the project and brings to mind the famous proverb,

“A society grows great when old men and women plant trees whose shade they know they shall never sit in.”

Thus, the 2021 translocation is an important and historic step in the global effort to conserve this iconic and much-loved Australian tree.

Further information

Doyle C (Host) (2021, April). Wollemi Pine: Surviving the furnace. [Audio podcast episode]. In Plant Heroes. Wollemi Pine; surviving the furnace by Plant Heroes

Hannam P (2021, 28 May). ‘Just fantastic’: Wollemi pine replanting effort wins global gong. The Sydney Morning Herald. ‘Just fantastic’: Wollemi pine replanting effort wins global gong

Hannam P (2021, 29 May). ‘Real sense of achievement’: The next step to preserve the Wollemi pine. The Sydney Morning Herald. ‘Real sense of achievement’: The next step to preserve the Wollemi pine

Zimmer HC, Offord CA, Auld TD, Baker PJ (2016) Establishing a wild, ex situ population of a critically endangered shade-tolerant rainforest conifer: a translocation experiment. PLOS One, 11(7), e0157559. Establishing a Wild, Ex Situ Population of a Critically Endangered Shade-Tolerant Rainforest Conifer: A Translocation Experiment

Box 1. Translocation timeline

• Sep 1994: David Noble discovers relict stand of Wollemi Pine in Wollemi National Park
• Dec 1994: Research on propagating the species commences
• Oct 2005: Auction of first-generation cutting-propagated plants followed by commercial release
• Dec 2006: Official species recovery plan identifies translocation as a potential strategy to mitigate extinction risk
• Aug 2012: Establishment of semi-wild, experimental translocation at Mt Tomah
• 2017: Desktop and field surveys of candidate translocation sites in Wollemi National Park commence
• May 2019: First Wollemi Pine saplings translocated into two remote canyons within Wollemi National Park
• Jun-Aug 2019: Supplementary watering trips to nurse translocated saplings through severe drought
• Summer 2019-20: Black Summer bushfires impact the wild sites and all three translocation sites
• Feb 2021: Translocation team awarded prestigious Species Recovery Grant from the National Geographic Society and the IUCN Species Survival Commission
• Apr-May 2021: Ground teams successfully replant 500 saplings across the two translocation sites in Wollemi National Park