Biological Importance 

This hotspot is composed of the island nation of Madagascar and several neighboring island groups the Mascarenes, Comoros, and Seychelles in the western Indian Ocean. Seychelles, Mauritius and the bulk of the Comoros are independent nations, whereas the island of Reunion is a French overseas department and the Comorian island of Mayotte is a French overseas territory. At 587,045 square kilometers (0.4% of the land surface of the planet), Madagascar is the largest oceanic island and the fourth largest island on Earth. The island nation is located approximately 400 kilometers from the eastern coast of Africa and, via the process of plate tectonics, is believed to have been isolated from other landmasses for more than 160 million years. This isolation has resulted in a number of distinct evolutionary lineages and high levels of endemism among groups of plants and animals that either were inhabitants of the original landmass before Madagascar's separation, or which colonized the "new" island later. This section in the ecosystem profile provides a brief overview of the biological importance of the entire Hotspot region. However, at this point CEPF will provide grant resources to projects within the boundaries of the nation of Madagascar. Other areas of the Madagascar and Indian Ocean Hotspot may become eligible for funding later.

Together, the other island groups add very little to the land area of the hotspot, yet they make a significant contribution to its biodiversity. Reunion and the Republic of Mauritius- which consists of the main island of Mauritius, Rodrigues, Round Island and a number of smaller islands- are located approximately 900 kilometers east of Madagascar and cover 2,040 square kilometers. The Comoros are located northwest of Madagascar in the Mozambique Channel and cover 2,171 square kilometers. Seychelles, with four main granitic islands, Mahé, Praslin, Silhouette and La Digue, and approximately 100 other granitic islands and coralline islets, covers an area of 455 square kilometers. Combined with Madagascar, these island groups bring the total area of the hotspot to 594,221 square kilometers.

In terms of the original extent of its native habitats, Madagascar and the Indian Ocean Islands represents the 10th largest of the 25 biodiversity hotspots that have been identified by Conservation International. It ranks 8th among the hotspots in terms of remaining intact habitat (approximately 18% of the original extent), according to the most recent estimates of tropical forest cover.

Levels of Biological Diversity and Endemism

High levels of biological diversity and endemism are found in Madagascar and the Indian Ocean Islands, not only at the species level, but at the genus and family levels as well. Current estimates put the number of plant species in Madagascar somewhere between 10,000-12,000, of which more than 80% (8,000-9,600 or 3.2% of the world total) are endemic. These species are represented by 160-181 families, of which 10 are endemic (Asteropeiaceae, Bembiciaceae, Didiereaceae, Didymelaceae, Diegodendraceae, Kaliphoraceae, Melanophyllaceae, Physenaceae, Sarcolaenaceae and Sphaerosepalaceae). Only the continent of Australia, more than an order of magnitude larger than Madagascar, has more endemic plant families (13). Of the island's 1,289 genera, 260 (20%) are endemic. Regional levels of plant endemism in Madagascar are also quite high. For example, 95% the plants of the southern spiny deserts are endemic at the species level and 48% are endemic at the genus level, not occurring anywhere else in Madagascar.

The Mascarenes (Mauritius and Réunion) have 108 families, 323 genera and 955 species of vascular plants, of which 38 genera and 697 species (73%) are endemic. Comoros has 136 families and 416 species, of which 137 species (33%) are endemic, and Seychelles has 93 families, 170 genera and 200-250 species, of which one family, 12 genera and at least 70 species (35% of the lower estimate) are endemic. Together, these smaller islands add one endemic plant family, 50 endemic genera and 904 endemic species to the figures for Madagascar, raising the totals for the hotspot to 11 endemic plant families, at least 310 endemic genera, and 8,904-10,504 endemic species. No other hotspot has this many endemic families, and only three -the Tropical Andes, Sundaland and the Mediterranean- exceed this number of endemic plant species.

Comparative figures for terrestrial vertebrate groups are mixed, but no less impressive. On Madagascar, while overall bird diversity is relatively low (only 250 species), 115 (46%) endemic. Furthermore, there is a high rate of family-level endemism, with five bird families (Brachypteraciidae, Leptosomatidae, Mesithornidae, Phillepittidae and Vangidae) restricted to the island. Comoros has 91 bird species, of which 23 (25%) are endemic; the Mascarenes have 17 endemic bird species (seven on Réunion, eight on Mauritius and two on Rodrigues); and Seychelles has 170 bird species, 11 endemic.

The recent global analysis of restricted-range bird species by BirdLife International highlights the importance of the Madagascar and Indian Ocean Islands Hotspot in its identification of 11 Endemic Bird Areas (EBAs), six of which are recognized at the critical level:
- West Malagasy Dry Forests, with eight restricted-range species (three endemic and four threatened);
- East Malagasy Wet Forests, with 23 restricted-range species (20 endemic and 14 threatened);
- East Malagasy Wetlands, with nine restricted-range species (six endemic and four threatened, including three critically endangered); br> West Malagasy Wetlands, with seven restricted-range species (four endemic and five threatened, including two critically endangered);
South Malagasy Spiny Forests, with 10 restricted-range species (eight endemic and two threatened);
- Comoros, with 18 restricted-range species (15 endemic and six threatened, including five critically endangered);
- Aldabra, with three restricted-range species (one endemic); Granitic Seychelles, with 12 restricted-range species (11 endemic and eight threatened, including four critically endangered);
- Réunion, with seven restricted-range species (four endemic and one endangered);
- Mauritius, with 10 restricted-range species (seven endemic and seven threatened, including four critically endangered); and
- Rodrigues, with two restricted-range species (both endemic and both threatened, one critically endangered).

The list of critically endangered birds in the Madagascar and Indian Ocean Hotspot is among the highest for any of the 25 hotspots identified by Conservation International. From Madagascar it includes the Madagascar serpent eagle (Eutriorchis astur), Alaotra grebe (Tachybaptus rufolavatus), Madagascar pochard (Aythya innotata), Madagascar fish eagle (Haliaeetus vociferoides), and Sakalava rail (Amaurornis olivieri). Comoros adds the Anjouan Scops-owl (Otus capnodes), Grand Comoro Scops-owl (Otus pauliani), Mount Karthala white-eye (Zosterops mouroniensis), Grand Comoro drongo (Dicrurus eminentissima), and Mayotte drongo (Dicrurus fuscipennis). From Seychelles, the list of includes the Seychelles Scops-owl (Otus insularis), Seychelles magpie robin (Copsychus sechellarum), Seychelles paradise flycatcher (Terpsiphone corvina), and Seychelles white-eye (Zosterops modestus). And the Mascarenes add five more: the pink pigeon (Columba mayeri), Mauritius parakeet (Psittacula eques), Mauritius olive white-eye (Zosterops chloronothos), Mauritius fody (Foudia rubra) and Rodrigues warbler (Acrocephalus rodericaus).

Of Madagascar's 300 reptile species, 274 (91%) are endemic, as are 36 out of 64 genera (56%). The Mascarenes add five endemic reptile species, Comoros 22 species, of which seven are endemic, and Seychelles 15 species, of which 14 are endemic. The island of Aldabra is also home to an endemic giant tortoise (Geochelone gigantea). Combined, the Madagascar and Indian Ocean Islands Hotspot is home to at least 327 reptile species, of which 301 (92%) are endemic. These figures rank an impressive seventh and fourth among the world's hotspots, respectively.

Frogs are the only amphibians found on Madagascar. Only one or two of the island's 178 species are introduced 99% are endemic. Neither the Mascarenes nor Comoros have indigenous amphibians, but Seychelles adds 12 species, of which 11 are endemic. Thus the entire hotspot is home to 190 amphibian species, of which 187 (98%) are endemic. These figures rank Madagascar and the Indian Ocean Islands Hotspot seventh among hotspots in terms of amphibian diversity and fifth in terms of endemism, with the highest percentage of amphibian endemism for any hotspot (except for Polynesia/Micronesia and New Zealand, which only have three and four amphibian species, respectively).

While mammalian species diversity in Madagascar is not exceptional, 78 (67%) of the 117 species are endemic; excluding bats and introduced species, the level approaches 100%. The Mascarenes add two endemic mammals to the hotspot total, Comoros another 12 species and two endemics, and Seychelles another two species, both endemic. Overall, the hotspot ranks only nineteenth out of 25 for mammalian diversity, but sixth in terms of mammalian endemism.

Madagascar's primates are unquestionably the most prominent group of mammals native to this hotspot. Although it is only one of 92 countries in the world with wild primate populations, Madagascar is responsible for 21% (14 out of 65) of all primate genera and 29% (5 out of 17) of all primate families (Cheirogaleidae, Lemuridae, Megaladapidae, Indriidae and Daubentoniidae), making it the single highest priority area on Earth for conserving primate diversity. All 36 primate species and 54 taxa currently described are endemic to the island, two species almost certainly having been introduced by man to neighboring Comoros. Eleven species of Madagascar's lemurs are considered critically endangered: the white-collared lemur (Eulemur fulvus albocollaris), Sclater's lemur (Eulemur macaco flavifrons), golden bamboo lemur (Hapalemur aureus), Alaotran gentle lemur (Hapalemur griseus alaotrensis), broad-nosed gentle lemur (Hapalemur simus), red ruffed lemur (Varecia variegatarubra), silky sifaka (Propithecus diadema candidus), diademed sifaka (Propithecus diadema diadema), Perrier's sifaka (Propithecus diadema perrieri), Tattersall's sifaka (Propithecus tattersalli) and crowned sifaka (Propithecus verreauxicoronatus).

Levels of Protection for Biodiversity

According to Conservation International's hotspot analysis, the remaining natural habitat in the Madagascar and Indian Ocean Islands Hotspot consists of approximately 59,038 square kilometers of tropical rainforest, tropical dry forest and xerophytic vegetation, only about 10% of the original extent of the vegetative cover. Of the remaining natural habitat, only 11,546 square kilometers, or just under 2%, is in officially protected areas. By far the largest amount of remaining habitat and most significant national system of protected areas within the hotspot are found in Madagascar; therefore it is the focus of this section and of the subsequent CEPF investment strategy.

The Ecoregions of Madagascar

Based on an action plan recently released by Madagascar's Association Nationale pour la Gestion des Aires Protégés (ANGAP), the national agency responsible for management of protected areas, the country can be divided into a series of Ecoregions and Transition zones which correspond roughly to earlier domains based on floristic composition.

The Eastern Ecoregion covers 115,617 square kilometers and is characterized by lowland rainforest occurring between sea level and 2,000 meters. It extends along Madagascar's east coast from just north of Sambava to Fort Dauphin. Only 35,229 square kilometers (30%) of this ecoregion's original forest cover remains; the largest remaining tracts are found in the northeastern and southeastern extent of its range. This is perhaps the richest region in Madagascar in terms of species diversity, as shown by studies of vascular plants and terrestrial vertebrates, and it is also characterized by local centers of endemism (e.g., the Masoala peninsula, the Andringitra massif and the regions of Andasibe and Zahamena).

The Central Ecoregion covers 170,887 square kilometers and is a heterogeneous ensemble of moist and dry formations that parallel the Eastern Ecoregion, extending westward across Madagascar's central plateau. This part of Madagascar has been largely deforested or modified by human activities; as a result, only 11,929 square kilometers (7%) of its original habitat remains intact.

The Northern Mountains Ecoregion, an area spanning 20,935 square kilometers, corresponds to the northern limits of the former Central Domain and is an area of high endemism for anthropods, amphibians, reptiles and rongeurs. It includes two geographically distinct high mountain regions, Tsaratanana and Marojejy. Approximately 8,664 square kilometers (41%) of this ecoregion's original forest cover remains intact.

The Northern Transition Zone is a relatively small area (5,524 square kilometers) of mixed forests growing above 800m and stretching coast to coast in a thin strip across northern Madagascar. This transition zone includes the Sambirano Domain, as well as the northeastern limits of the Central Domain. Approximately 1,028 square kilometers (19%) of these forests remain in their original condition.

The Western Ecoregion is the largest of Madagascar's ecoregions, extending over an area of 211,045 square kilometers. It is a vast zone of dry deciduous forests on Madagascar's western coastal plains and limestone plateau, ranging from sea level to 800 meters and covering the area from Antsiranana in the north to Morombe in the southwest, as well as a smaller block in the extreme northern part of the country which represents a major center of plant endemism. The bulk of this ecoregion is characterized by a dry season of almost seven months and, along with the eastern lowland forests, should be considered among the most endangered forest ecosystems in Madagascar. Unfortunately, only 31,372 square kilometers (15%) of the Western Ecoregion's original forest cover remains intact. Included within this larger region is the Analavelona Transition Zone, a tiny fragment of moist forest with characteristics of the Central Ecoregion.

The dry forests of the Southern Ecoregion cover an area of 57,721 square kilometers and are characterized by deciduous thicket or thorn scrub. They extend southward from Morombe along the coast, covering much of Madagascar's southern tip from sea level to 400 meters. Rainfall in this region is sparse and irregular. As a result, these are the driest forests in Madagascar and this is the region popularly referred to as the spiny desert. An estimated 19,131 square kilometers (33%) of the Southern Ecoregions original forests remain intact.

The Status of Protected Areas in Madagascar

Madagascar's national system of nature reserves (Réseau National des Aires Protégés) is composed of 46 protected areas representing three categories: 15 national parks, 8 integral nature reserves, and 23 special reserves. The table below provides information on the status, size, management and location of protected areas within the major ecoregions of Madagascar.

A recent analysis conducted by Conservation International has identified the following 23 protected areas as most important to the conservation of threatened lemur diversity in Madagascar. These areas are indicated by an asterisk (*).

Protected Area	Created	Area	Govt Region	Ecoregion	Authority
National Parks
Andohahela *	8/7/971	760	Toliara	Eastern and Southern	ANGAP
Andringitra *	10/19/91	312	Fianarantsoa	Eastern and Central	WWF
Ankarafantsika 3 *	12/31/97	605	Mahajanga	Western	ANGAP
Baie de Baly	12/18/97	574	Mahajanga	Western
Isalo	7/19/62	815	Fianarantsoa	Central	ANGAP
Kirindy-Mitea	12/18/97	722	Toliara	Western
Mananara-Nord	7/25/89	230	Toamasina	Eastern	UNDP/UNESCO
Mantadia *	1/11/89	100	Toamasina	Eastern	ANGAP
Marojejy *	5/19/81	601	Antsiranana	Northern Mountains	WWF
Masoala *	3/2/97	2,300	Toamasina	Eastern	ANGAP/WCS
Midongy-Sud	12/18/72	1,922	Fianarantsoa	Eastern and Central
Montagne d'Ambre *	10/28/58	182	Antsiranana	Central	ANGAP
Ranomafana *	5/27/91	416	Fianarantsoa	Eastern	ANGAP
Tsingy de Bemaraha 4	8/7/71	666	Mahajanga	Western	ANGAP
Zahamena4	8/7/97	414	Toamasina	Eastern	CI
Integral Nature Reserves
Betampona *	12/31/27	22	Toamasina	Eastern	ANGAP
Lokobe	12/31/27	7	Antsiranana	Northern Transition Zone	ANGAP
Tsaratanana	12/31/27	486	Antsiranana	Northern Mountains	ANGAP
Tsimanampetsotsa	12/31/27	432	Toliara	Southern
Tsingy de Bemaraha *	12/31/27	854	Mahajanga	Western	ANGAP
Tsingy de Namoroka *	12/31/27	217	Mahajanga	Western
Zahamena *	12/31/27	225	Toamasina	Eastern	CI
Zombitse-Vohibasia2	12/18/97	172	Toliara	Central and Western	WWF
Special Reserves
Ambatovaky *	10/28/58	601	Toamasina	Eastern
Ambohitantely	2/12/82	56	Antananarivo	Central	ANGAP
Ambohijanahary	10/28/58	248	Mahajanga	Central
Analamazaotra *	7/21/70	8	Toamasina	Eastern	ANGAP
Analamera *	2/20/56	347	Antsiranana	Western	ANGAP
Andranomena *	10/28/58	64	Toliara	Western	ANGAP
Anjanaharibe-Sud *	10/28/58	321	Antsiranana	Northern Mountains	WWF
Ankarana *	2/20/56	182	Antsiranana	Western	ANGAP
Bemarivo	9/10/56	116	Mahajanga	Western
Beza-Mahafaly	6/4/86	6	Toliara	Southern	ESSA
Bora	2/20/56	48	Mahajanga	Western
Cap Sainte Marie	10/24/62	18	Toliara	Southern	ANGAP
Forêt d'Ambre *	10/28/58	48	Antsiranana	Central	ANGAP
Kalambatrita	4/24/59	283	Fianarantsoa	Central
Kasijy	9/10/56	198	Mahajanga	Western
Mangerivola	10/28/58	119	Toamasina	Eastern
Maningoza	2/20/56	79	Mahajanga	Western
Manombo *	12/5/62	53	Fianarantsoa	Eastern	ANGAP
Manongarivo	2/20/56	327	Antsiranana	Northern Mountains and Northern Transition Zone	ANGAP
Marotandrano	2/20/56	422	Mahajanga	Eastern and Central
Nosy Mangabe *	12/14/65	5	Toamasina	Eastern	ANGAP/WCS
Pic d'Ivohibe	9/16/94	35	Fianarantsoa	Eastern and Central	WWF
Tampoketsa-Analamaitso	10/28/58	172	Mahajanga	Central

1. established originally as an Integral Nature Reserve
2. established originally as a Classified Forest
3. currently an Integral Nature Reserve; proposed National park, but not yet decreed
4. portion of former Integral Nature Reserve that has been upgraded to National Park status

(*) protected areas of major importance for threatened lemur conservation ANGAP: Association Nationale pour la Gestion des Aires Protégées
CI: Conservation International
ESSA: University of Antananarivo, Department of Water and Forests
UNDP: United Nations Development Program
WCS: Wildlife Conservation Society
WWF: World Wide Fund for Nature

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