Hurricane palm tree, extinct in the wild, finds refuge in Rio de Janeiro's Botanical Garden

A year ago, the last hurricane palm (Dictyosperma album var. conjugatum H.E.Moore & J.Guého) still found in its natural habitat, on the Mauritius Islands off the coast of Madagascar, Africa, died. As a result, this variety of palm tree has been extinct in the wild since September 2024. However, ex situ conservation (cultivation outside the natural environment) brings a glimmer of hope for the species. In the Rio de Janeiro Botanical Garden, there are four adult individuals that bear fruit.

In an article published on the Mongabay website in November 2024, journalist Shanna Hanbury reports that the last hurricane palm tree native to its natural habitat on Round Island fell after a storm in mid-September. At 9 meters tall, it was an attraction on the small island of only 1.7 km², a strategic conservation area in Mauritius. Experts and authorities have been working for years to conserve this species, among others, but it was not possible to prevent the loss of the last wild specimen.

According to the article, the population of this palm tree began to decline in the 19th century with the arrival of British colonists who brought goats and rabbits to Round Island. These animals became invasive to the local ecosystem, devastating seedlings and causing erosion of the topsoil that helped keep the palm trees standing.

The International Union for Conservation of Nature (IUCN) estimates that 38% of the planet's tree species are threatened with extinction, and most of these are found on islands, which are ecosystems increasingly threatened by climate change, especially in tropical regions, with rising sea levels and more violent storms. In 2022, the IUCN already classified the hurricane palm as critically endangered (CR), as there was only one mature native specimen left. Another native specimen of this variety survived until 1994, when it was knocked down by Cyclone Hollanda.

From seeds of the hurricane palm lost in 1994, the Mauritian government, the Mauritian Wildlife Foundation, and the Durrell Wildlife Conservation Trust (UK) have collaborated to produce seedlings and cultivate 18 young hurricane palms on Ile aux Aigrettes, a coral islet near Round Island. This is an effort to try to save this variety from total extinction and, perhaps in a few decades, to reintroduce it into its natural habitat.

"However, seedlings that come from the same individual, that is, from the same matrix, do not have genetic diversity, which tends to weaken the species. Therefore, in the medium or long term, it may become completely extinct," explains researcher Marcus Nadruz, coordinator of Living Collections at the Rio de Janeiro Botanical Garden (JBRJ).

There are currently four individuals of hurricane palm, also called princess palm, cultivated at the JBRJ Arboretum. “It is a very beautiful palm tree, which has a very different grayish-green palm heart that is inedible,” says Nadruz. He adds that the genus Dictyosperma is monospecific, meaning it has only one species, Dictyosperma album, which is divided into three varieties: album, aureum, and conjugatum, all of which are present in the Garden.

The good news is that the four hurricane palms (Dictyosperma album var. conjugatum) at the Rio de Janeiro Botanical Garden produce flowers and fruit. This means that the JBRJ may be able to supply seeds for plans to reintroduce this variety into the wild.