Blog

July 2023 - Margaux Rojat has joined us as PhD Student

Margaux holds a master degree in ecology and conservation from the University of La Réunion. She will explore competitive exclusion and other multi-species interactions between alien and native plants in La Réunion based on forest inventories, community models and pot experiments, and under the supervision of Raphaël Pélissier, Ghislain Vieilledent, Mark van Kleunen and Robin Pouteau. Welcome to the team! ©Margaux ROJAT

October 2023 - LiDAR campaign

With the Observatory of Universe Sciences of La Réunion (OSU-R), we welcomed colleagues from University of Cherbourg and their Matrix 300 UAV for LiDAR measurements over our forest plots. They got a taste of the challenging environmental conditions associated with montane tropical forests. ©Robin POUTEAU

Early November 2023 - Field work campaign started

We collected ecological data on the last populations of (top to bottom): the vulnerable shrub Dombeya acutangula subsp. acutangula var. acutangula, the endangered endemic trees Obetia ficifolia and Polyscias cutispongia and the critically endangered woody plants Abutilon exstipulare, Polyscias aemiliguineae, Tabernaemontana persicariifolia  and Volkameria heterophylla. A lot of invasive alien plants, showers but also fun! ©Robin POUTEAU, Anaëlle REGEN, Sarah ROUSSEL & Dominique STRASBERG

January 2024 - The cyclone season is open!

Because of the tropical cyclone Belal, the tropical storm Candice and other major meteorological events that caused significant human losses and material damage in Mascarene Islands, our field work campaign has been slowed (only five days this month). ©Météo-France & Robin POUTEAU

February 2024 - 2024 is off to a good start

We discovered that a population of the small tree Dombeya acutangula first described in 2009 as made of 20 individuals has doubled since then. This is thanks to a high number of seedlings and juveniles at the foot of a steep cliff where a highly productive 'mother tree' found refuge (lying tree in the middle picture). Nice to see that this species is still regenerating in a few places. Dombeya acutangula is considered vulnerable in Réunion and critically endangered in Mauritius and Rodrigues.  We also noted that a population of two individuals of the endangered archipelago endemic shrub Fernelia buxifolia remains stable since 2009, and that one of them is even flowering and producing fruits! ©Robin Pouteau

Late February 2024 - Pot experiment coming soon...

For her PhD, Margaux is setting up an ambitious pot experiment that aims to better understand interactions between endemic threatened trees and alien invasive plants. This experiment, designed with the help of Mark van Kleunen (Konstanz University) and managed with the help of Henri Hoarau (CBNM), will be hosted in one of the shade houses of the project partner CBNM in Saint-Leu (a big thank you goes to them!). Below are:

• the tunnel where the experiment will take place;

• Margaux and Henri caring for the babies;

• flowers of the Reunion endemic CR small tree Indigofera ammoxylon in the CBNM arboretum;

• a flowering individual of the Mascarene endemic CR tree Foetidia mauritiana;

• seedlings of the Mascarene endemic CR tree Terminalia bentzoe.

©Robin POUTEAU

March 2024 - A nice example of management efforts

We made two inventories in one of the last relicts of semi-dry forest (it is thought that only 1% of the original ecosystem remains) in Cap Francis, northwest of Réunion. This site hosts an exceptional richness in threatened endemic trees. It is jointly managed by ONF (French national forest office) and the Conservatoire du littoral (coastal protection agency). Conserving such sites can have an enormous impact in securing the endemic flora of Réunion. Below are:

• a view on the river Grande Chaloupe;

• Elise and Rémi-Paul with the rock Cap Francis in the background;

• the highly invasive alien wine Hiptage benghalensis, sometimes forming impenetrable thickets over native vegetation and causing breakage of supporting trees, has been cut;

• the invasive alien tree Albizia lebbeck has been debarked, allowing light reaching the forest understory;

• seedling of the Mascarene endemic EN tree Scolopia heterophylla;

• seedling of the Mascarene endemic CR tree Foetidia mauritiana;

• young fruit of the Mascarene endemic CR tree Foetidia mauritiana;

• ripe fruit of the Mascarene endemic VU shrub Erythroxylum hypericifolium. We measured hundreds of them;

• a flowering individual of the Réunion endemic CR shrub Croton mauritianus;

• a flowering individual of the Mascarene endemic VU shrub Dombeya acutangula subsp. acutangula var. acutangula;

• the Mascarene endemic CR tree Ruizia populnea;

• female of the alien chameleon Furcifer pardalis.

©Robin POUTEAU

April 2024 - Three days in La Montagne

We went on a three day-field trip in the north-east of the island. There, the invasive alien liana Hiptage benghalensis is causing dramatic changes to forest habitats and endemic trees often remain aggregated in tiny relict patches. It was a tiring but exhilarating adventure. Below:

• the Mascarene endemic CR tree Ceodes lanceolata known in Réunion from only five individuals distributed among three sites lost in a dense matrix made of the invasive alien tree Syzygium jambos;

• Margaux and the Mascarene endemic CR tree Foetidia mauritiana sometimes forming populations of several individuals including juveniles;

• flower of the Mascarene endemic CR tree Hibiscus columnaris;

• Arnaud climbing on the Réunion endemic EN tree Polyscias cutispongia to collect leaves;

• discovery of a new population of the Mascarene endemic EN liana Hugonia serrata;

• the team in Ravine à Malheur with a majestic Polyscias cutispongia in the background;

• Elise, Margaux and Rémi-Paul measuring leaf traits in the kitchen after a hard day's work. 

©Robin POUTEAU & Arnaud RHUMEUR