Famous as the land of the Dodo, the biodiversity of Mauritius is quite rich and provides key raw materials and essential ecosystem services. For definition’s sake, biodiversity refers to the variability that exists amongst all living sources and the complex interactions in their different ecosystems . As things currently stand, Mauritius is found in the Madagascar and Indian Ocean Islands biodiversity hotspot and has been designated by the IUCN as ‘Center of Plant Diversity’ . The small island of Mauritius is characterized as having a high endemism level (found only in that particular place) due to its remote location, small size and diverse topography, age and tropical climate.
When Mauritius was originally discovered, trees and plants covered most of the surface area. Following human settlement on the island, vast expanses of forest were cleared for agriculture and development, a process which only got worse over the years. Today, less than 2% of the original forest remain on mountain ridges and offshore islets. Statistically, 691 species of plants are found in Mauritius, with 273 island endemics and 150 Mascarene (consisting of the islands Mauritius, Rodrigues and Reunion) endemics. Of these, 141 of flowering Mascarene indigenous plants are classified as ‘critically endangered’, 55 species as ‘endangered’, 98 species as ‘vulnerable’ and 61 species are already extinct.
Thus, beautiful plants like the Trochetia boutoniana (Boucle d’oreille), which is also the national flower of Mauritius, Crinum mauritianum (Fleur de Lys) and Elaeocarpus bojeri (Bois dentelle) bloom only on the island as do majestic ancient trees like Bois d’Ebene, Bois Jaune and Bois de bitte. Most of these native trees and shrubs normally grow in the dense forests or on mountain tops while endemic plants can be seen at the botanical gardens such as the Vallée d’Osterlog Endemic Garden in the south, the SSR Botanic Garden in the north, the Aborteum at Curepipe and offshore islets like Ile aux Aigrettes in the south. A complete list of the native flora of Mauritius can be accessed here.
As a remote island in the Indian Ocean, only small animals like birds, insects and reptiles that could fly or swim were originally discovered in Mauritius. Introduced animals refer to those who were brought deliberately like cattle or accidentally like rats. Initially, there were 17 species of reptiles in Mauritius, but today only 12 remain; of these 11 species are endemic, 7 of which are found on the offshore islets where they were able to survive in the absence of introduced animals.
As for mammals, there is just one species, namely the fruit-eating bats: Pteropus niger is found on the mainland of Mauritius and Pteropus rodricensis on Rodrigues Island. These creatures are big with golden fur and are commonly seen flying around at dusk in search of food (fruits, nectar and pollen). Additionally, 40 species of endemic butterfly species have been recorded in Mauritius and 125 land snail species, of which 43 have gone extinct. Amongst the 30 species of land birds, 9 native species are still in low populations including the Pink Pigeon, Mauritian Kestrel and the Mauritius Olive-White eye. A list of the native fauna with their pictures can be accessed here.
Brightly colored day geckos like the Phelsuma, the endangered Pink Pigeons, the harmless Keel-scaled boa and the interesting Telfair’s Skink can be found in Mauritius only. Though there are not many endemic animal species, some amazing creatures are known to have inhabited Mauritius only like the Dodo, the Broad Billed Parrot, the Mauritius Blue Pigeon and the real Giant Tortoises which have now all gone extinct. While it is believed that Dodos and Giant Tortoises were preyed on for their meat by the early settlers, other animals have disappeared as a result of deforestation leading to habitat loss and reduced food availability in addition to the introduction of predators that fed on the eggs and young ones. The few species that are now left are highly protected and located in nature reserves on the offshore islets such as Round Island, Serpent Island and Flat Island and in the dense native forests of the Black River Georges National Park.
There are actually many threats that the biodiversity of Mauritius faces that prevent the regeneration of plants and put animals at risk. As a rapidly growing nation, unplanned and unsustainable development and nature destruction have been ongoing at the sake of biodiversity loss. Even protected areas have been mismanaged leading to more economic investment and compromising conservation goals while the endangered bats have been considered for culling under pressure from fruit producers . Recently, the government has leased many of the offshore islet nature reserves for tourism activities that greatly endanger the endemic biodiversity in the form of introduced predators and destruction of habitats . Although stringent legislation regarding biodiversity preservation exits, oftentimes it is only on paper.
As it happens, there is a lot of competition between native species and invasive ones in many spots of the indigenous forest. Exotic species such as the Chinese Guava (Psidium cattleianum) compete with the endemic plants for space and nutrients preventing their growth and regeneration. Likewise, introduced animals like pigs trample on the soil thereby destroying seedlings and/or encourage the growth of invasive species by dispersing the seeds. Other animals like monkeys destroy the flowers and fruits of plants and trees further reducing growth success. While all the above-mentioned points form part of any natural ecosystem, small population sizes and habitat fragmentation add stress to the growth of the native Mauritian species. As for the native animals, the greatest threat is habitat destruction by humans and cyclones resulting in a decline in their numbers. Moreover, they are also subject to diseases and invasive alien species like mongooses and feral cats that feed on their eggs and adult ones.
The government of Mauritius has taken important steps to preserve the biodiversity of the island both for ecological and socio-economic reasons. These include in-situ conservation of native species where propagation of seeds is carried out, supervising Conservation Management Areas (CMA) at the Black River Georges National Park, expanding the protected area network in the PAN (Protected Area Network) Project and maintenance weeding in protected areas. Captive breeding programmes and introduction into the wild are carried out for animal species in addition to predator control and native habitat restoration.