Last Wild Tree of Its Kind Survives on Remote Chilean Island
On Chile’s Robinson Crusoe Island in the South Pacific, a single tree of Dendroseris neriifolia clings precariously to a steep cliff. Estimated to be around 150 years old, it is the last known wild individual of its species. Conservationists have recently collected seeds from this tree in a desperate bid to prevent its total extinction in the wild.
Unique and Threatened Genus
All 11 species of the genus Dendroseris are exclusive to the Juan Fernández Archipelago off Chile. These trees, known for their striking yellow, orange, or white flowers, have been nearly wiped out by extensive habitat degradation, invasive plants, and damage from introduced mammals such as goats and rodents.
According to Paulina Hechenleitner, a research associate at the Royal Botanic Gardens, Kew, U.K., only one known wild individual of the critically endangered D. neriifolia remains on Robinson Crusoe Island, one of the three main islands in the archipelago. She noted that the tree hangs off a remote cliff that “is extremely difficult to access, requiring specialist fieldwork and careful planning to avoid any harm.”
Daring Seed Collection and Banking
Every year, local conservationists attempt to collect seeds from the tree’s one-seeded fruits. However, fruiting is irregular, and some seasons the fruits produce few or no viable seeds, Hechenleitner said.
This year, the team collected about 400 seeds. Of these, 29 were considered potentially viable and were sent to the Millennium Seed Bank (MSB) at Kew, the world’s largest wild plant seed conservation program. There, researchers used X-ray imaging to confirm that 24 seeds showed the presence of embryo development.
Alice Hudson, MSB partnership officer at Kew, explained that these 24 “good seeds” were split into three groups of eight. “An initial eight were trialled for germination to see if we had the conditions right,” Hudson told Mongabay by email. “Now we know that the methodology works we plan to germinate another 8 of the seeds. The final 8 will be banked at the MSB for long-term conservation.”
Path to Restoration
The seedlings will be shared with U.K. botanical gardens to refine and improve cultivation and propagation methods under different growing conditions, Hechenleitner said. “Increasing seed production is key to strengthening seed bank collections and generating material that can eventually be repatriated to Chile for habitat restoration. Continued seed collection from the last wild tree, whenever viable crops are produced, will help secure remaining genetic diversity.”
The ultimate goal of the project is to restore wild populations of the tree. But “this will require long-term investment in habitat restoration, invasive species control, monitoring, and carefully planned reintroductions,” Hechenleitner added.
Larger Conservation Implications
Survival of Dendroseris trees is crucial for species that depend on them, including the critically endangered Juan Fernández firecrown (Sephanoides fernandensis), a hummingbird that forages on nectar from the trees’ flowers.
Hudson emphasized the significance: “This genus [Dendroseris] only occurs on the Juan Fernández Islands, if they’re lost that’s a whole group of species gone with unique diversity.”
Banner image of the last known wild individual of Dendroseris neriifolia, courtesy of Royal Botanic Gardens, Kew.
Credits and Additional Information
This article is based on reporting by Mongabay. The topics discussed include biodiversity loss, conservation, and seed banking. For more on environmental ideas shaping action, refer to the Mongabay Newscast series.