Madagascar ericoid thickets


The Madagascar ericoid thickets is a montane shrubland ecoregion, found at higher altitudes on Madagascar's four major mountains.

Geography

The ecoregion covers the area above 1800 m elevation on Tsaratanana, Marojejy, Ankaratra, and Andringitra Massif. The ericoid thickets are surrounded at lower elevations by the Madagascar subhumid forests ecoregion. The total area of the ecoregion is. On Tsaratanana the thickets are higher up, starting above 2,500m. There are smaller areas of thicket in Anjanaharibe-Sud Reserve in the north and Andohahela National Park to the south.

Flora

The ericoid thickets are characterised by shrubs of the flowering plant families Asteraceae, Ericaceae, Podocarpaceae, Rhamnaceae and Rubiaceae. They include a large number of endemic plants, many of whose closest relatives live in South Africa and the highlands of East Africa. Andringitra alone is home to 150 vascular endemics, including 25 species of orchid.

Fauna

These high points of Madagascar are home to less diverse animal life than on the lower slopes, but with a high proportion of endemics. The area was not thoroughly researched until the 1990s. There are at least ten species of endemic and near-endemic reptiles including the dwarf gecko Lygodactylus arnoulti.

Threats and preservation

The highlands are vulnerable to fire and to conversion to cattle pasture, although Tsaratanana, Andringitra and Marojejy are all protected areas.