MU014
Rodrigues mainland


Site description (2001 baseline):

Site location and context
The site covers the central ridge and valleys radiating from it, including most of the native and exotic woody vegetation on Rodrigues. It occupies about one half of the island. The main habitats for native birds are exotic forest and thickets; the forest is dominated by Tabebuia pallida, Mangifera indica, Casuarina equisetifolia and other exotics, and a few native tree species, while most thickets are of exotic Syzgium jambos. Such habitat is patchily distributed, mainly in valleys, with the largest stands in the sheltered valleys of Solitude and Cascade Pigeon. Native plants elsewhere are widely scattered, although concentrations occur at a few sites.

Key biodiversity
See Box and Table 2 for key species. Two species are endemic to the Rodrigues mainland. Populations of both have fluctuated, reaching a low point of less than 10 pairs each following habitat loss and severe cyclones in the late 1960s. However, as woody habitat has recovered and been protected, and in the absence of catastrophic cyclones, their populations have increased. In 1998, the distribution of Foudia flavicans included most of the island’s woody vegetation taller than 5 m, and is still expanding as new plantations reach maturity. In 1999, the population was 911–1,200 birds and the main sites were Solitude, Cascade Pigeon, Saint Gabriel, Sygangue, Grande Montagne and Mont Malartic. Acrocephalus rodericanus is much rarer, but still probably less at risk than for a long time; in 1999, the population was estimated at 150 birds, probably slowly increasing. Its main haunts in 1999 were Solitude, Cascade Pigeon, Montagne Cimetière, St Gabriel, Grande Montagne and Mont Limon. Pterodroma baraui has also once (1974) been found nesting, but this incidence has not been repeated.

Non-bird biodiversity: Plants: a devastated but still unique flora, with 36–38 taxa of endemic flowering plants (19–21 are Endangered, seven Vulnerable and eight Rare), including Ramosmania rodriguesiana (=R. heterophylla), Dombeya rodriguesiana and Gouania leguatii, all known from single individuals; three endemic ferns (one Rare, one Endangered). Mammals: Pteropus rodricensis (CR). Molluscs: 10 endemic land-snail species, four highly endangered.



Pressure/threats to key biodiversity
Two localities in the IBA are Nature Reserves for native plants. Much bird habitat is protected watershed (River Reserve or Mountain Reserve), in which human habitation and wood-cutting are prohibited. However, wood-cutting and livestock-grazing still affect some areas. Reforestation and natural regeneration combined with forest protection, spurred by the need for watershed protection in this water-stressed island, has been the key to the recovery of the native birds (and also of the fruit bat Pteropus rodricensis); the absence of catastrophic cyclones since 1972 has also helped. However, much reforestation has involved exotic trees, and so this process is not suited to native ecosystem conservation. To this end, sites rich in native plants have been selected for native ecosystem rehabilitation, and it is hoped that native birds will increasingly also occupy these as the native trees and shrubs mature. Sites are fenced to exclude browsing or grazing animals and wood-cutters; exotic plants are removed and natives replanted. The main sites are Grande Montagne (10.2–13.8 ha) and Anse Quitor (7.7–10.3 ha; areas vary according to source) Nature Reserves, but Cascade Mourouk (proposed reserve), Cascade Pigeon and Cascade Saint Louis are also priorities for future rehabilitation. Management is accompanied by a public-awareness campaign promoting environmental education and wildlife conservation. Foudia flavicans and Pteropus rodricensis have bred in captivity, but releases have not been needed because of increases in wild populations. Actual and potential (based on the ecological history) threats are habitat destruction and degradation, cyclones and effects (competition and/or predation) of exotic animals, including the possibility of introductions of new exotics.


Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Rodrigues mainland (Mauritius). Downloaded from https://datazone.birdlife.org/site/factsheet/rodrigues-mainland-iba-mauritius on 22/11/2024.