Black ebony  (Diospyros tessellaria)

Classified as Vulnerable (VU) on the IUCN Red List (1).

Recognised for the highly prized quality of its timber, black ebony is a canopy tree that was exploited on a large scale during the Dutch occupation of Mauritius in the 17th century (2) (3) (4) (5). Reaching up to 20 metres in height (6), it has a characteristic black trunk, often covered in white lichen (2), and bears sweet-smelling, white flowers, occasionally with a pink tinge (5). The green, egg-shaped fruit are fleshy and fragrant (2) (5).

Black ebony is the most widespread of the eleven endemic Diospyros (Ebony) species on Mauritius (5). It has been able to establish at low, mid, and high altitudes (5), and is mostly found in the south-west and eastern mountain ranges of the island (1).

Occurs in lowland evergreen forest and upland rainforest, where it often forms a dominant component of the canopy (1).

The relatively widespread distribution of black ebony compared to the other endemic Diospyros species, is almost certainly accounted for by the nutritious quality of its fruit (5). Sufficiently fleshy and fragrant to be eaten by the Mauritian flying fox (Pteropus niger), the fruit, along with the precious seeds, are sometimes dispersed over considerable distances. However, these fruit bats are also fond of eating the flowers, which must also have a negative effect on the tree’s reproductive potential (7).

In addition to the heavy selective exploitation of black ebony during the 17th century, clearance for agriculture, forestry, villages and towns has irreversibly transformed the Mauritian landscape (2) (3) (4) (5). When Mauritius was first colonised, it was covered in dense vegetation, but today native forests occupy less than two percent of the island, and are restricted to mountain ridges and protected reserves (2). Invasive alien plants, which outcompete native plants for water, light and nutrients, present an additional threat to the remaining native forests (2) (3).

Given that the last IUCN assessment of black ebony was conducted in 1998 (1), the current status of this species is not well known. However, in order to protect the remaining native forests and their endemic flora, the National Parks and Conservation Service has established fenced off Conservation Management Areas in the Black River Gorges National Park that exclude invasive species and disturbance. In addition, the Native Plant Propagation Centre was established in 1997 to propagate threatened native and endemic plants in a controlled nursery (2).

To find out more about conservation in Mauritius, visit:

• Republic of Mauritius National Parks and Conservation Service (NPCS):
  www.gov.mu/portal/sites/moasite/nationalpark/index.htm
• Mauritian Wildlife Foundation:
  www.mauritian-wildlife.org