Madagascar Group Overview

At 587,000 square kilometres, Madagascar is the world’s fourth largest island after Greenland, New Guinea and Borneo. Madagascar is also recognised as one of the world’s top ten hotspots for biodiversity (Mittermeier et al., 1999; Myers et al., 2000; Brummitt & Nic Lughadha, 2003).

Estimates vary for the total number of plant species present on the island. The lowest figure - 7370 (including Pteridophytes) (Perrier de la Bathie, 1936) is clearly out of date and certainly too low. A highest estimate of 12,000 species has been suggested by Guillaumet (1984). Myers et al. (2000) give 12,000 as their estimate of total plant species in the hotspot of Madagascar, but this figure includes the species present on the surrounding islands of Mauritius, Reunion, the Seychelles and the Comoros. Either way Madagascar has an extremely diverse flora and fauna - and its most striking feature is the degree of endemism both at species level – and at higher taxonomic levels.

The figures of Myers et al. (2000) give a level of species endemism at 81% of the total flora. This is broadly consistent with older figures – for example Perrier de la Bathie identified 5820 of his 7370 species as endemic in 1936 (86%). Humbert (1959), editor of the Flore de Madagascar et des Comores, proposed that 6400 of his known 7800 species were strictly endemic (81%). Perrier de la Bathie (1936) identified 238 (20%) of the 1289 native genera as endemic. White (1983) identified eight endemic plant families out of a total of 191. These were Asteropeiaceae, Didiereaceae, Didymelaceae, Diegodendraceae, Geosiridaceae, Humbertiaceae, Sphaerosepalaceae and Sarcolaenaceae. Some of these family groups have since been revised as a result of phylogenetic studies (e.g. Didieraceae is no longer considered endemic as three continental African genera have been sunk into it (Schatz, 2001)).

In addition to its considerable biodiversity value, Madagascar scores highly on the second criterion of Myers et al. (2000) - degree of risk. Madagascar is one of the world’s poorest countries and this, combined with a large population growth rate, increases pressure on the land for production. Deforestation has been occurring across the country for hundreds of years, and around 90% of Madagascar’s primary vegetation appears to have been lost since humans first inhabited the island around 2000 years ago (Du Puy and Moat, 1996).

RBG Kew has been working in Madagascar for 17 years, and our work there has mainly been in carrying out plant diversity research in the form of systematic treatments of key families for the region. In addition, Kew’s Madagascar Geographical Information System Project, started in 1994, has made a major contribution to the management of protected areas in Madagascar. The past five years have seen the publication of two comprehensive monographs –the Legumes of Madagascar and the Palms of Madagascar. Kew staff have also been involved in the production of a complete checklist of all the orchid species present on the island and, in collaboration with the Missouri Botanical Garden, the Generic Tree Flora of Madagascar – which gives descriptions, illustrations and keys for all tree genera on the island.

More recently, the focus of RBG Kew’s programme in Madagascar has centred around the conservation and sustainable utilisation of Madagascar’s plant diversity as defined in the Convention on Biological Diversity and the Global Strategy for Plant Conservation (l. RBG Kew has a permanent base in Antananarivo with an office/house and seven Malagasy staff, and is currently supporting three PhD and four Masters students in botanical studies. Current projects in Madagascar have a combined budget in excess of $1000,000, and ten Kew staff members spend a significant amount of their time working on the flora of Madagascar.

Our long term aim is to develop a team of Malagasy botanists with the skills to support Kew’s programme in Madagascar, and provide a service to users of plant information in Madagascar. In particular, we want to encourage plant identification skills and good practice in specimen collecting, plant naming, databasing, report writing etc. There is a growing demand for species inventory work in particular, and field identification skills will always be essential to Kew’s work in Madagascar.In 2002 RBG Kew signed an Accord de Siege with the Government of Madagascar, formalising our status as a recognised conservation NGO in Madagascar.

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