Why these species?
Indonesia is home to many remarkable trees. Towering dipterocarps reach heights of over 70m, mighty ironwoods produce one of the world’s hardest timbers and durians are notorious for producing a pungent fruit (which you may love or hate, depending on your taste!).
These versatile and valuable trees are under threat from logging and loss of their forest home to palm oil plantations and forest fires. More than 125 Indonesian tree species are known to be Critically Endangered and nearly 1,500 tree species are found nowhere else in the world.
Despite the importance of the country’s tree species, they receive very little conservation attention compared to other species groups. While many animals, including tigers, orang-utans and hornbills, are prioritised for conservation under national action plans enshrined by Indonesian law, until recently, no such plans have been made for the country’s trees.

Lowland tropical rainforest in Waigeo Island, Raja Ampat. Credit: Yanuar Ishaq Dc/FFI
What are we doing about it?
In 2016, FFI Indonesia, as a part of the Global Trees Campaign, established the Indonesian Forum for Threatened Trees, bringing together the country’s leading tree experts and institutions. Through this forum, a National Strategy and Action Plan for Conservation (NSAPC) was developed listing 12 priority tree species, putting threatened trees on the national conservation agenda.
Of the 12 priority tree species, four have been highlighted as in the greatest need:
- Lagan Bras, Dipterocarpus cinereus, thought extinct in 1998, is Critically Endangered and is found only on Mursala Island in Sumatra.
- Pelahlar, Dipterocarpus littoralis, is also Critically Endangered and is restricted to only one island, Nusakambangan in Java.
- Kokoleceran, Vatica bantamensis, like the Javan rhino, is found only in Ujung Kulon National Park, western Java.
- Vatica javanica ssp. javanica, is found only in Capar Forest Reserve, Brebes, and central Java.
To build on this momentum, GTC is now focussing on enabling and mobilising other NGOs and local government departments to increase action for threatened trees on the ground. Actions have included the training and mentoring of local practitioners and institutions in tree conservation techniques and engagement with provincial government bodies to encourage the incorporation of threatened tree species action into management plans for key sites.

Members of the Indonesia Forum for Threatened Trees. Credit: FFI
Key achievements
Work is on-going to increase conservation efforts for Indonesia’s 12 priority tree species, with a special focus on the four species mentioned above. Legal protection has already been secured for two species, Lagan Bras and Pelahlar, and the Indonesian Forum for Threatened Trees is pressing for more of the priority species to gain formal protection. Other priorities for these species include the development of nurseries and species-specific propagation and planting guidelines to assist regeneration activities.
Fieldwork at key sites has increased our knowledge of population and species distributions which, in turn, has enhanced seedling collection, reinforcement efforts and nursery development. For example, surveys for Pelahlar covering all of Nusakambangan Island found 48 mature trees, propagation trails have begun and there is a broad range of stakeholders keen to get involved with conserving the tree.

Threatened tree nursery in West Kalimantan. Credit: Jaswadi/Head of Kebun Bibit Rakyat, Desa Pelang Kalbar
On Mursala Island, surveys in August 2018 expanded the known population of Lagan Bras from three adults and a handful of seedlings to 163 individuals, 30 of which were mature trees. This fieldwork found a total of 26 Dipterocarpaceae species on the island, 20 of which are threatened with extinction. In addition to Lagan Bras, the confirmed presence of the Critically Endangered Hopea bancana on the island is of particular note, as this species is believed to be found nowhere else in the world. Subsequently, the importance of Mursala Island has been recognised and the island has been proposed as an additional priority location for tree conservation within the national strategy.
We continue to work through and with the Indonesian Forum for Threatened Trees to deliver targeted training to conservation practitioners, provide small grants to initiate new action for threatened trees, mentor groups or individuals implementing new projects, and engage with provincial conservation management authorities to encourage incorporation of threatened trees into key site management plans.
Acknowledgements
From 2015-18, this work was supported by large number of funders including the United Nations Development Programme, the Directorate of Biodiversity Conservation of Indonesia’s Ministry of Environment and Forestry, Yayasan Belantara and the Indonesia Science Center. Many institutions continue to make this work possible including Bogor Botanical Garden and the Indonesia Science Center.
Contact details
For more information on this project, please contact globaltrees@fauna-flora.org