Terrestrial Ecosystems


Before the arrival of people, the island of Mauritius was entirely covered with forests, which varied in structure and composition due to altitude, soil type and rainfall.  The Domaine de Bel Ombre includes three of these types of forests which have been relatively well preserved over the centuries. Different plant species have adapted to live in wet upland forests and dry lowland forests as well as in intermediate forests. Some species are found in all three forest types including; the black ebony tree (Diospyros tessellaria), red saga wood (Doratoxylon apetalum), and colophane batard (Protium obtusifolium).  The forests also shelter several rare endemic animal species namely the Mauritius kestrel (Falco punctatus), the pink pigeon (Columba mayeri), the echo-parakeet (Psittacula eques) and the Mauritius fruit bat (Pteropus niger)– the only known terrestrial endemic mammal on the island.


Forest features

Forest types

Rainfall, altitude and soil type have led to the development of ten different types of forests around Mauritius. These can be classified as follows:


Lowland (0-200m)

Intermediate (200-400m)

Upland (>400m)

Coastal forest: Ile aux Aigrettes, Ilot Gabriel, Gris-Gris

Semi-dry forest (1,500 mm/year): Corps de Garde


Upland marsh: bog, dominated by Pandanus

Coastal marsh and mangrove forest: South-East coast

Sub-humid forest (2,500 mm/year): dominated by Diospyros & Canarium such as Bel Ombre

Heath (3,500-4,500 mm/year): a stunted forest with thick-leaved plants on leached soils. Dominated by Philippia and Phylica. (Plaine Champagne, Pétrin)

Dry forest (>1000mm/year): a colourful forest


Upland wet forest (,4,500 mm/year): tall forest on deep, rich soils, e.g. Maccabé, Brise Fer

Palm-rich forest (>1,000mm/year): an open forest with many palms (i.e Round Island)


Mossy forest (4,000-5,000 mm/year, 600-800m): cloud forest, rich in epiphytes

Source:  R. Atkinson and J-C Sevathian, A guide to the plants in Mauritius, The Mauritian Wildlife Foundation


Forest adaptations

The plants of Mauritius - as is the case for many island ecosystems – have developed peculiar adaptations to their unique environment. They are more resistant to cyclones, with a high tree density and a relatively low canopy, along with buttress roots which anchor trees to the ground. Many native trees also produce leaves in different shapes, colours and sizes on the same plant –known as heterophylly – an adaptation which is thought to protect trees from herbivorous critters and enhance the capture of sunlight in dense canopies.  Many trees also have flowers directly on their trunks, which helps not only insects but also birds and reptiles such as the Mauritius gecko pollinate the flowers. Lastly, a distinctive feature of many plants is their large, fleshy and brightly coloured fruit with a hard seed inside, which are thought to have been eaten by Dodos, skinks and giant tortoises. The latter would have therefore played an important role in seed dispersal.  


Forest ecosystem functions and services

Forests support the decomposition of organic matter, soil nutrient cycling processes and water retention and supply. They also help regulate the climate, control erosion, regulate disturbances and provide important places for recreation, for example, the Black River National Park hosts nearly 100,000 visitors annually. Adequately managed forest resources can contribute to environmental rehabilitation, creation of employment, supply of wood and non-wood products, food security, ecotourism, recreation and national wellbeing. Lastly, they play a vital role in the conservation of biodiversity and wildlife.


Threats and management

Four hundred years of deforestation, over-exploitation of native species, intensive agricultural development and the introduction of exotic species have severely degraded the native forests of Mauritius, leaving only 2% of the original forest intact and causing the extinction of many species. It is believed that the last vestiges of native forest could be lost within fifty years without active management.


Active management of native forests requires the removal of Invasive Alien Species (IAS) and the control of introduced animals which disrupt the natural processes of the native forests. Some of the most damaging IAS include the Chinese guava (Psidium cattleianum) and the traveller’s palm (Ravenala madagascariensis), while pigs (Sus crofa), monkeys (Macaca fascicularis), rats (Ratus ratu) and deer (Cervus timorensis) eat native seeds and seedlings, disturb the soil and disperse invasive seeds. Active management may also involve replanting native species in areas that have been cleared of IAS. Since May 2009, Bel Ombre has been actively engaging in management and reforestation of 9 hectares of native species and forests on its lands, in collaboration with the Mauritian Wildlife Foundation.





Some of the drier regions of Mauritius, mainly the northwest and west coast were historically made up of palm savannah, which can still be found on the outer islands such as Gunner’s Coin and Round Island. Below the forest treeline, the trees become sparser and the soil is covered by grasses punctuated by palm trees. In contrast, the Bel Ombre savannah is a result of historical deforestation and development as the trees were exploited for their wood or cleared to make way for agriculture, sugar cane fields as well as the development of deer farming.  In this region, the resulting savannah is used as a hunting reserve, for the Java rusa deer, Indian hares, the grey francolin and pheasants among others. Native palms and other trees common to dry lowland forests and grasslands have been replaced by acacia, Ravenala as well as common fruit trees such as mango.


Palm savannahs and native grasslands

Writings from the earliest explorers and settlers only provide some clues as to what the landscape used to look like. It is believed that parts of the island – mostly the drier northwest and western coastal areas of the island were covered by palm savannahs and grasslands. Nowadays, these only exist in the northern shelf islets. Some authors, such as Bernardin de Saint Pierre, mention a green savannah devoid of rocks between Le Morne and Bel Ombre. It is also believed that grasslands developed in some parts of the island as a result of grazing by the giant tortoises. The grasses in these habitats may have included the native vetiver (Vetiveria arguta) and the Spades grass (Zoysia tenuifolia), which are still found on Round Island and are thought to be rather resistant to grazing.


Man-made grasslands of Bel Ombre

The grasslands of Bel Ombre are located on the upper part of the Domaine, which was once heavily forested. Exploitation of the native hardwoods coupled with deforestation for agricultural purposes have left the hills barren. Although the native ecosystem had been disrupted, these hills provided an ideal grazing area for the Java rusa deer (Cervus timorensis), and several species of grasses were introduced to support this species including, stargrass (Isachneum aristica) and elephant grass (Pennisetum purpureum).






Estuarine ecosystems do not only provide important habitats for aquatic and terrestrial plants and animals but also serve ecological functions such as the regulation of stream flow, storage and release of water and removal of harmful materials from the water.  Although most of the riverine native vegetation has gradually given way to exotic species, freshwater fauna – though threatened – have remained. These include insects such as dragon flies and damsel flies, freshwater snails, crustaceans and fish such as eels and gobies. River ecosystems have acted as vital corridors connecting wildlife populations across landscapes fragmented by human activity or structures.


River ecosystem features

River ecosystems comprise the river corridor—the river channel, riparian zone, floodplain, and alluvial aquifer. River ecosystems are lotic ecosystems – meaning ecosystems where there is a continuous flow of water. These ecosystems are distinguished by the unidirectional flow of water, a state of continuous physical change and a high degree of spatial and temporal heterogeneity, thus creating micro-habitats. Animals and plants which inhabit river systems are specialized to live in flow conditions.  River ecosystems are home to an important number of bacteria as well as phytoplankton, algae and plants. The latter are limited by flow, light, water chemistry and type of substrate. Algae and plants play an important role in river ecosystems as they help to form microhabitats that shelter fish and other organisms from predators and from the current. They also provide a vital food source.


Ecosystem function and services

Rivers link the land and ocean and transfer materials from terrestrial to ocean ecosystems. They serve important geological functions through erosion and carve out the Earth’s surface into distinct landforms. Upland, riverbeds may be composed of boulders, cobbles and coarse sediments. Further downstream, sediments break down to form finer sediments which can eventually form bars, islands or natural levees.

Riparian vegetation plays an important role in maintaining healthy river systems, they provide organic matter, habitat and spawning sites for many aquatic animals and act as a corridor for animals to move between different ecosystems. The vegetation also plays a vital role in stabilizing sediment and reducing erosion.


Threats and management

River ecosystems, particularly native riparian vegetation has suffered from the effects of deforestation and the introduction of exotic species that dominate the banks and areas around most rivers in Mauritius, including Rivière Citronniers and Jacotet River. Rehabilitating river ecosystems entails restoring the native vegetation. Types of plants and species used in restoration include larger trees such as bois d’olive (Cassine orientalis) and bois de boeuf (Gastonia mauritiana) as well as small trees and bushes such as bois de reinette (Dodonea viscosa) and bois de ronde (Erythroxylon sideroxyloides).





Wetlands are areas covered by shallow water either permanently or seasonally. They are home to unique plants and wildlife that have adapted to soil which is saturated by water. There are several types of wetlands found in Mauritius. Those most commonly found on the coast are coastal marshlands, intertidal mudflats or mangrove forests. They provide critical resting places for migratory birds and serve vital ecosystem functions such as filtering water from upland rivers and streams removing pollutants and other harmful materials and trapping sediments. Wetlands act like giant sponges which help absorb excess water and control flooding. Some of the common plant and animal species found in wetlands are the southern cattail (Typha domengensis), the common moorhen (Gallinula chloropus), the green-backed heron (Butorides virescens) and the mallard duck.


Wetland features

Wetlands are distinguished from other landforms and water bodies by the presence of characteristic vegetation which is adapted to the submerged, generally anaerobic soil.  In Mauritius, coastal marshlands have formed in low-lying depressional areas and in the coastal backwash region behind sand dunes where the soil has low permeability and storage capacity.  The vegetation in these marshlands tends to be dominated by the cattail (Typha domengensis) and the fire fern (Acrostichum aureum).


Wetland ecosystem functions and services

Wetlands and coastal marshlands act as water filters, mitigate floods, are a carbon sink and provide habitat for many important species of plants, birds and invertebrates.  Coastal marshlands trap sediments and pollutants from rivers, streams and surface runoff before they enter the lagoon, with plants playing an important role in filtering the water. Wetlands help regulate water quantity and groundwater discharge, acting as recharge areas when the surrounding water table is low and as a discharge zone when it is too high. As a discharge zone, they contribute significantly to flood mitigation, particularly in coastal areas that have been built-up and where soil permeability has been reduced. They take up and store nutrients found in the surrounding soil and water –and play a role in carbon sequestration, necessary for climate change mitigation. Lastly, they are an important habitat for wildlife, particularly for aquatic and migratory birds.


Threats and management

Coastal freshwater marshlands around Mauritius have been severely degraded over time due to backfilling, dumping and contamination by pollutants. Backfilling is the main threat faced by wetlands as many are located on privately owned properties, which are prime spots for residential developments. This has destroyed an important number of wetlands and has led to flooding in surrounding residential areas.  Coastal marshlands have also been used for dumping solid waste, mainly construction debris used as aggregate for backfilling.

Wetlands are protected under the Ramsar International Convention and are designated Environmentally Sensitive Areas (ESA) under Mauritius law. Efforts to further protect the existing wetlands are essential while restoration of wetlands can be done by recreating the physical space necessary for wetlands, re-establishing water flow and replanting aquatic plants, thereby attracting water birds and other wildlife.