Avoiding tree extinctions in Mauritius

Conservation problem
Mauritius and Rodrigues have many endemic species. Many trees have few individuals left after centuries of land use change, and threats from invasive species (plants, livestock and rats), logging, soil erosion and low seed viability

Project Goal
To monitor wild populations, update phenological calendars, collect seeds, propagate seedlings and plant these in protected areas for the continued survival of nine threatened tree species on Rodrigues and one on Mauritius

Which species and why?

The project focuses on 10 target endemic species on Mauritius and Rodrigues. Most of these are all down to the last few individuals or have proved extremely difficult to propagate and face multiple threats from land use change, invasive species and altered ecologies (either a lack of dispersers or pollinators or shifting phenologies due to climate change. The 9 target species from Rodrigues are Antirhea bifurcata, Badula balfouriana, Dombeya rodriguesiana, Foetidia rodriguesiana, Zanthoxylum paniculatum, Eugenia rodriguensis, Hibiscus liliiflorus, Polyscias rodriguesiana and Pyrostria revoluta. The target species from Mauritius is Zanthoxylum heterophyllum.

Zanthoxylum paniculatum flowers on Rodrigues island

Zanthoxylum paniculatum flowers on Rodrigues Island

What are we doing?

In partnership with the Mauritian Wildlife Foundation (MWF), we are doing the following activities for each of these species:

  • Creating new species recovery plans.
  • Monitoring wild and replanted populations.
  • Collecting and propagating seeds and cuttings.
  • Planting propagated individuals into protected sites, like nature reserves and the Mourouk Gene bank.
  • Increasing the protection of remaining wild individuals.
  • Translocating trees in danger from development.
Key achievements

Wild populations have been monitored to ensure the plants’ phenology is better understood and updated so that seeds can be collected when the trees are ready.

MWF propagates many thousands of seedlings each year, of which some 543 individuals of 10 focal species have been planted back into protected areas like the Grand Montagne and Anse Quitor Nature Reserves, and Ile aux Aigrettes, since the project began in 2019.

Some of the last trees of 7 of the target species (Z. heterophyllum, Z. paniculatum, B. balfouriana, E. rodriguensis, F. rodriguesiana, H. liliiflorus and Polyscias rodriguesiana) are having fences built around the surviving trees to protect them from and their progeny from livestock and other wildlife to give them a better chance of increasing natural regeneration.

Badula balfouriana fruits wrapped in mesh to protect them from predation by rats

Badula balfouriana fruits wrapped in mesh to protect them from predation by rats

Plans are also under way to translocate 5 individual trees of target species, along with other trees, that are threatened by airport expansion development due to take place in 2022/2023. This is with the support from experts from the Naples Botanical Garden, Florida.

At the same time, more realistic plans have been developed for the Rodrigues Botanic Garden established in Mourouk, with support from an expert from the Leon Levy Native Plant Preserve. The Rodrigues Regional Assembly has accepted these plans and begun the process of implementation.

Contact details

For more information on this project, please contact alex.hudson@bgci.org.

Did you know?

Roasted seeds from the Critically Endangered ParanĂ¡ pine are a popular winter snack in southern Brazil.