Mauritius has one of the most interesting floras in the World due to its high endemicity. The island has over 670 species of native flowering plants of which 300 (45%) are endemic to the island. The flora of Mauritius has 7 endemic genus and most of the native species are endangered but according to the IUCN red list 150 native species are critically endangered as they are known from less than fifty individuals in the wild. Over the past 400 years, Mauritius has known large scale forest clearance for agriculture and urban development, and added to the introduction of invasive plants and animals competitors, a significant proportion of native plants are either extinct or on the verge of extinction.

The project aims to survey rare native plants and take steps to save the genetic diversity through appropriate actions including nursery propagation and replanting in a field gene bank. The “Upland Field Gene Bank” project , started at a pilot level at Pigeon Wood in the Black River Gorges National Park close to a large forest area containing a high number of Critically Endangered native plant species. The rare plants in the field gene bank will be subsequently mass propagated in different nurseries for future restoration projects.

The prospecting work is the more labour intensive part of the project and involves staff surveying remote areas, based on previous distribution records and from the Mauritius Herbarium sheet specimens. This is also the most thrilling part of the project, since exciting discoveries can be made eg the rediscovery of the ’Fleur de Lys du pays’ Crinum mauritianum near Perrier Reserves, which until then was presumed extinct in the wild.

Individuals of rare plant species in the wild are tagged and geographic coordinates are taken using a GPS, which are then reproduced on a GIS map and plant material (seeds/seedlings/cuttings) are collected for propagation in the Pigeon Wood rare plant nursery.

Plant materials from rare species are propagated in the upland nursery. Cuttings are generally preferred but when sufficient material cannot be obtained, seeds and seedlings are collected and sown in the nursery. Successful plants are then planted outdoors in an adjacent 40m x 40m grass land in the field gene bank which acts as an ex-situ collection of rare plants, where genetic diversity is maintained. By March 2006, 105 individuals from 9 Critically Endangered species were planted in the field gene bank. Recently, grafting techniques have been used to increase the rate of propagation of rare species with the collaboration on the Horticulture Division of the Ministry of Agro-Industry.

For example, ’Bois dentelle’ Elaeocarpus bojeri a small tree is known only from two individuals in the wild. In an attempt to propagate this species, eight successful grafts (4 from each plant) have been obtained in July 2005. One graft from each plant has been planted in the Pigeon Wood nursery whilst the remaining grafts have been provided to other nurseries (Forestry Service, NPCS and Horticulture Division).

Excess stock of the native rare plants that have been propagated in our nursery will be transferred to the government nurseries as replicates of this genetic diversity. In addition, some individuals from rare species can be re-introduced in the wild either to re-establish or re-inforce known sub-populations. For instance, the Pigeon Wood nursery produced ’Vacoas’ Pandanus microcarpus seedlings from seeds obtained near the Perrier Nature Reserve. These seedlings will be planted in the Reserve, in collaboration with the Forestry Service.

Sponsored By:
Air Mauritius
Barclays
Chester Zoo (North of England Zoological Society)
Forestry services
National Parks and Conservation Service
UNDP - GEF/SGP

Last update: 26 December 2006