Isalo National Park is a
National Park
A national park is a natural park in use for conservation purposes, created and protected by national governments. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns. Although individua ...
in the
Ihorombe
Ihorombe is a region in Madagascar. It borders Haute Matsiatra region in north, Atsimo-Atsinanana in east, Anosy in south and Atsimo-Andrefana in west. The capital is Ihosy and the population was 418,520 in 2018. The area of Ihorombe is and it ...
Region of
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...
, in the southwestern corner of the Province of
Fianarantsoa
Fianarantsoa is a city (commune urbaine) in south central Madagascar, and is the capital of Haute Matsiatra Region.
History
It was built in the early 19th century by the Merina as the administrative capital for the newly conquered Betsileo kin ...
. The closest town is
Ranohira, and the closest cities are
Toliara
Toliara (also known as ''Toliary'', ; formerly ''Tuléar'') is a city in Madagascar.
It is the capital of the Atsimo-Andrefana region, located 936 km southwest of national capital Antananarivo.
The current spelling of the name was adopted ...
and
Ihosy
Ihosy is a city (commune urbaine) with 283,047 inhabitants (2015) in Ihorombe Region in central south Madagascar.
Ihosy is the capital of Ihorombe Region, as well as of the district of Ihosy.
Geography
Ihosy is an important crosspoint for t ...
. It is a sandstone landscape that has been dissected by wind and water erosion into rocky outcrops, plateaus, extensive plains and up to deep canyons. There are permanent rivers and streams as well as many seasonal watercourses. Elevation varies between .
History and significance
Isalo National Park was created in 1962 and has been administered by the Madagascar National Parks authority since 1997. The
Bara people
The Bara people are a Malagasy ethnic group living in the southern part of the central plateaus of Madagascar, in the Toliara Province, concentrated around their historic capital at Ihosy. The Bara are the largest of the island's zebu-herd ...
have traditionally inhabited this area, a nomadic people subsisting on cattle (
zebu
The zebu (; ''Bos indicus'' or ''Bos taurus indicus''), sometimes known in the plural as indicine cattle or humped cattle, is a species or subspecies of domestic cattle originating in the Indian sub-continent. Zebu are characterised by a fatty ...
) farming. There are burial sites of the Bara people and some older burial sites of the
Sakalava.
Isalo is primarily within the
dry deciduous forests ecoregion, an ecoregion in which natural vegetation has been reduced by almost 40% of its original extent.
It also includes landscapes considered part of the
subhumid forests ecoregion, an ecoregion that is home to numerous endemic species and has been given Critical/Endangered status because only small areas of native habitat remain and most of those are highly fragmented.
The woodlands of Isalo are dominated by the endemic tree tapia (''
Uapaca bojeri''). This is a woodland type that is restricted in distribution;
[ found only in Madagascar's central highlands.] Some of the largest intact areas of tapia woodlands are found in Isalo.[ There are numerous narrowly endemic plant species found here, including 13 species that have been found only in Isalo and another 35 that are rare species, known from 2-5 sites.] Not only is Sarcolaenaceae a plant family found only in Madagascar, two species within it (''Sarcolaena isaloensis'' and S''chizolaena isaloensis'') have only been found in Isalo NP.[ There are also unusual lichens here, including the type specimen and only known location for the narrowly endemic ''Isalonactis madagascariensis''.]
Climate
Isalo National Park is in the arid western part of Madagascar, within the western dry deciduous forest bioclimatic zone. The area has a hot, dry climate with two seasons; a cooler-drier season and a warmer-wetter season. Each lasts from 5–7 months.[ Temperatures range between , the average annual temperature is and the average rainfall is (at Ranohira). Precipitation is lowest in June, averaging . December thru February are typically the wettest months. Rainfall in January averages ,] but the 2018/2019 wet season saw heavy rainfall, with of rain falling in January alone.
Geology
Located in the southern part of the Morondava Basin, the sedimentary Isalo Group is the main geological formation of the park, forming the Isalo Massif. The group is up to 6,000m thick, of Triassic to early Jurassic origin and made up of coarse-grained sandstone deposited by braided streams. The Isalo Massif has been eroded by wind and water, resulting in deep canyons, sandstone domes, flat-topped mountains and "runiform" mountains - steep sided outcrops that have been dissected into odd-shapes. These odd shapes are referred to as "runiforme", based on the French word for "carved".[
]
Tourism
A local guide is required for visitors entering the park, and guides and porters can be hired in Ranohira. Treks in the park can last from several hours to a week or longer. The park includes several natural swimming pools which are popular among tourists, and are excellent sites to see the Benson's Rock Thrush. The main threat to this park comes from illegal wildfires set in the park. The wildfires limit the extent of forest and maximize grasslands used by cattle.
Fauna
Fourteen species of mammals are reported for Isalo NP,[ including several different species of ]lemur
Lemurs ( ) (from Latin ''lemures'' – ghosts or spirits) are wet-nosed primates of the superfamily Lemuroidea (), divided into 8 families and consisting of 15 genera and around 100 existing species. They are endemic to the island of Madaga ...
.
Over 100 species of bird have been found here, including Benson's rock thrush (''Monticola sharpei bensoni''), the knob-billed duck
The knob-billed duck (''Sarkidiornis melanotos''), or African comb duck, is a duck found in tropical wetlands in Sub-Saharan Africa, Madagascar and the Indian Subcontinent from northern India to Laos and extreme southern China.
Most taxonomic ...
(''Sarkidiornis melanotos'') and the Madagascar ibis (''Lophotibis cristata'').[
Twenty four amphibians and 47 reptiles have been documented in Isalo National Park, including a number of new “candidate” species. Species endemic to the Isalo area include four amphibians ('' Gephyromantis azzurrae'', '' Mantella expectata'', '' Mantidactylus noralottae'', and the ]Malagasy rainbow frog
''Scaphiophryne gottlebei'', commonly known as the Malagasy rainbow frog, ornate hopper, rainbow burrowing frog, red rain frog or Gottlebe's narrow-mouthed frog, is one of the most highly decorated frogs from Madagascar. The primary threats to th ...
(''Scaphiophryne gottlebei'') and one reptile species (''Trachylepis
''Trachylepis'' is a skink genus in the subfamily Mabuyinae found mainly in Africa. Its members were formerly included in the " wastebin taxon" '' Mabuya'', and for some time in '' Euprepis''. As defined today, ''Trachylepis'' contains the ...
nancycoutuae'').[ Notable examples include the Madagascar ground boa (''Acrantophis madagascariensis''), ]Dumeril's boa
''Acrantophis dumerili'', commonly known as Dumeril's boa, is a species of non-venomous snake in the family Boidae. The species is endemic to Madagascar. No subspecies are currently recognized.
Etymology
The specific name, ''dumerili'', is in ...
(''Acrantophis dumerili'') and the white-lipped bright-eyed frog
The white-lipped bright-eyed frog (''Boophis albilabris'') is a species of frog in the family Mantellidae.
It is endemic to Madagascar. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane ...
(''Boophis albilabris'').[
]
Flora
Botanical inventory of the Isalo region began with collections by Perrier de la Bâthie in 1910. Only 10 of the over 400 species that have been documented in Isalo are non-native species. Most (over 70%) are vascular plants that are endemic to Madagascar. There are 13 species that have been found only in Isalo and another 35 are rare species, known from 2-5 sites.[ The following table lists the species known only from Isalo NP.
Some entire families of plants are endemic to Madagascar. Examples of three of these families can be found in Isalo; Asteropeiaceae, Sarcolaenaceae and Sphaerosepalaceae.][ Not only is Sarcolaenaceae a plant family found only in Madagascar, two species within it (''Sarcolaena isaloensis'' and S''chizolaena isaloensis'') have only been found in Isalo NP.][
]
Lichens
The lichens of Madagascar Little work has been done on the lichens of Madagascar, so while over 500 species of lichens have been documented, more are expected. Madagascar can be divided into two major habitats that can be associated with lichen distribution. Wet tropical are ...
are poorly known, but over 500 species have been documented. Only about 20 species are found in the dry areas of the country. Several of these have been documented in the Isalo area,[ including the type specimen and only known location for the narrowly endemic ''Isalonactis madagascariensis''.][
]
Vegetation
Isalo is primarily within the dry deciduous forests ecoregion, an ecoregion in which natural vegetation has been reduced by almost 40% of its original extent.[ It also includes isolated forest patches classified as part of the subhumid forests ecoregion, an ecoregion that is home to numerous endemic species and has been given Critical/Endangered status because only small areas of native habitat remain and most of those are highly fragmented.][ Six main habitats have been described in Isalo NP.]
1. Sclerophylous woodlands
The sclerophyllous (hard-leafed, drought adapted) woodlands of Isalo are dominated by the endemic tree tapia ('' Uapaca bojeri''). This is a woodland type that is restricted in distribution; found only in Madagascar's central highlands.[ Some of the largest intact areas of tapia woodlands are found in Isalo.][ These woodlands are adapted to regular burning and are characterized by a relatively open canopy dominated primarily by tapia, but other trees may include members of the family ]Euphorbiaceae
Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as '' Euphorbia paralias'', are herbs, but some, ...
or the endemic family Sarcolaenaceae
The Sarcolaenaceae are a family of flowering plants endemic to Madagascar. The family includes 79 species of mostly evergreen trees and shrubs in ten genera.
Recent DNA studies indicate that the Sarcolaenaceae are a sibling taxon to the family ...
. The main components of the shrub layer are made up of species from the families Asteraceae, Rubiaceae, and Leguminosae, but herbs and grasses form the main understory.[ Endemic Kalanchoe and Aloe species grow in this habitat.][
]
2. Evergreen humid forest
These forests are associated with moist habitats such as near streams or in the deep ravines. Native forests found in deep canyons have palm species ('' Ravenea'' and '' Dypsis'' species), '' Breonadia salicina'', '' Weinmannia'' sp., '' Voacanga'' sp. and '' Dracaena'' sp. Some of these moist habitats however are now dominated by introduced species such as '' Melia azedarach'', ''Mangifera indica
''Mangifera indica'', commonly known as mango, is a species of flowering plant in the family Anacardiaceae. It is a large fruit tree, capable of growing to a height of . There are two distinct genetic populations in modern mangoesthe "Indian type ...
'' or ''Eugenia
''Eugenia'' is a genus of flowering plants in the myrtle family Myrtaceae. It has a worldwide, although highly uneven, distribution in tropical and subtropical regions. The bulk of the approximately 1,100 species occur in the New World tropics, ...
'' sp.[
]
3. Pandanus thickets
Pandanus thickets, dominated by ''Pandanus
''Pandanus'' is a genus of monocots with some 750 accepted species. They are palm-like, dioecious trees and shrubs native to the Old World tropics and subtropics. The greatest number of species are found in Madagascar and Malaysia. Common names ...
pulcher'' occur associated with shallower valleys or small stream are where the forest is degraded and frequently burned.[
]
4. Dry (xerophytic) vegetation
This habitat is associated with dry rocky areas, including steep slopes and ridges. Although vegetation is sparse, a number of endemic species are found in these habitats, including '' Xerophyta'' sp., elephant's foot ('' Pachypodium rosulatum'' var. ''gracilius'') and the narrow endemic ''Aloe isaloensis''.[
]
5. Secondary shrub communities
Secondary shrub communities are found where the slopes of the Isalo Massif contact fields or pastures. The most common species in these communities are listed as:[ '']Mimosa
''Mimosa'' is a genus of about 590 species of herbs and shrubs, in the mimosoid clade of the legume family Fabaceae. The generic name is derived from the Greek word (''mimos''), an "actor" or "mime", and the feminine suffix -''osa'', "resemb ...
latispinosa,'' '' Vangueria madagascariensis'', '' Maesa lanceolata'', '' Aphloia theaeformis'', ''Crotalaria
''Crotalaria'' is a genus of flowering plants in the family Fabaceae (subfamily Faboideae) commonly known as rattlepods. The genus includes over 700 species of herbaceous plants and shrubs. Africa is the continent with the majority of ''Crotala ...
'' sp., and '' Tamarindus indica''.
6. Grasslands
Native grasslands, probably once restricted to small patches, are thought to have expanded as a result of intensive burning, primarily to facilitate cattle grazing. Grasslands (also called pseudo-steppes) are now widespread in Isalo, dominated by ''Aristida similis'' and '' Aristida rufescens''[ as well as '']Trachypogon
''Trachypogon'' is a small genus of African and Latin American plants in the grass family. Crinkleawn grass is a common name for plants in this genus.
; Species
* '' Trachypogon chevalieri'' (Stapf) Jacq.-Fél. - western + central Africa
* '' Tr ...
'' sp. or '' Heteropogon'' sp. Frequent burning maintains the grasslands and prevents tree regrowth.[
]
Gallery
File:Sign for Isalo National Park.jpg, Sign for Isalo National Park
File:Lemurien10-2006.JPG, Verreaux's sifaka at Isalo National Park
File:Eulemur rufifrons, Isalo National Park 2007-03-01.jpg, Red-fronted brown lemur at Isalo National Park
Red-fronted_brown_lemur_6.JPG, Red-fronted brown lemur showing fangs
Brown lemur Isalo.JPG, Red-fronted brown lemur
Lemur Catta02.jpg, '' Lemur catta''
Pachypodium Rosulatum Gracilius 01.jpg, '' Pachypodium rosulatum gracilius''
Elephants foot plant 1.JPG, Elephants foot plant at Isalo National Park
Elephants foot plant 2.JPG, Elephants foot flower at Isalo National Park
Natural Swiming Pool, Isalo National Park (3955536504).jpg, Waterfall and ''Piscine Naturelle''
Canyon des Makis & Canyon des Rats - Isalo-Gebirge.jpg, Canyon des Makis
Isalo National Park 02.jpg, Lush and arid landscape
IsaloRock.jpg, Eroded Rock formations at Isalo National Park
Isalo National Park 05.jpg, Standing Stones at Isalo National Park
Lichens3 Isalo.jpg, lichens growing on the rocks at Isalo
Lichens4 Isalo.jpg, lichens growing on the rocks at Isalo National Park, Madagascar including Dermatiscum thunbergii
See also
* List of national parks of Madagascar
References
External links
Official website (in French)
{{Authority control
National parks of Madagascar
Ihorombe
Protected areas established in 1999
1999 establishments in Madagascar
Madagascar dry deciduous forests
Madagascar subhumid forests
Important Bird Areas of Madagascar