Preliminary results of the biological research in the Hatokaliotsy region, South-West Madagascar 

(Czech version)

Pavel Hošek, Ivo Dobšíček, Libor Kunte, Jiří Bálek

SUMMARY

The paper will summarize biological  data collected in and near the Hatokaliotsy region, south-west  Madagascar. The basic vegetation types will be preliminarily delimited and described. Checklist and distribution of the succulent plant species growing in the region will be given in context with their general distribution in Madagascar. The reptile species present in the region as well as registered arthropode  species of selected groups (Cassidinae s. lat., Scorpionida, Scarabeidae, Cerambycidae) will be stated.  Biological significance of the region, its recent degree of anthropic deterioration, and the forms of human pressure, will be assessed.
 

1. INTRODUCTION

1. 1. South-West Madagascar

The Hatokaliotsy region is located in the south-west Madagascar, being an extremely dry area from the climatic point of view. This fact, in addition to the long-term isolation of the island from the outer world (Rabinowitz, 1983), has generated very specific and unique plant and animal societies with high percentage of endemic species. In many taxonomic groups the endemism rate both in the level of the species and family reaches 50 to 100 per cent.
Go to the figure number 1 Fig. 1. The south-west of Madagascar is the dryest part of the island, and Hatokaliotsy belongs to the absolutely dryest areas (Battistini, 1964a). The rare rainfalls begin in December and end in March or April, but in some years may not appear at all (e.g. 1990-1992). The greater graph shows the variations in total annual rainfall between different years, as they were measured in the 50ies at several meteorological station in villages near Hatokaliotsy. The smaller graph shows variations during the year in the village Itampolo (directly on the Hatokaliotsy border). 
All the south-west area is predominantly covered with so-called spiny bush (bush epineaux). According to Keraudren (1961) and Koechlin (1972) the spiny bush plant communities can be characterized by the following characteristics:
 - grass cover thin, missing in extreme habitats
 - moss cover mostly does not exist
 - hemicryptophytes and terrophytes very rare
 - epiphytic, saprophytic and parasitic plants very rare
 - abundance of spiny and thorny plants, „bottle“ trees, succulent and cereiformic elements including palms
 - morphological and physiological adaptations similar to those of American arid continental formations
 - floristic composition of the spiny bush parallels with the African equatoreal dry-forest formations
According to Keraudren (1961) the spiny bush consists of three layers:
1. tree layer – reaches mostly 8 – 12 m, exceptionally 15 – 30 m above ground. It is created mostly by small trees in the common sense of the word, and also by Didiereaceae family species (succulent phanerophytes) and upright-growing trees (Adansonia – up to 30 m). The densest layer is 2 – 3 m above ground. Mostly deciduous and semi-deciduous species are concerned. There are many species of the Euphorbiaceae family, which are much different from the African ones in their habitus (6 – 8 m tall, with woody trunk, and their succulency is apparent in branches and leaves). The Didiereaceae form the highest layer, and the „bottle trees“– Adansonia, Moringa – are also present.
2. liana layer – in the dry season is presented only by woody aerial organs. Many climbing species are morphologically unique, belonging to phanerophytes (Keraudren, 1961). Surprising abundancy of the Asclepiadaceae (particularly Cynanchum) and Cucurbitaceae families is in contrast with low occurence of Rubiaceae, Asteraceae, Fabaceae, Rhamnaceae, Vitaceae, and Passifloraceae families.
3. lower layer – is biologically the most complex regarding the diversity of elements creating them. The grass stands are rare and more-less local, and the herbs in general are found only in a certain period of the year. In contrast, many perennial herbs and herb succulent species (Kalanchoe, Aloe) occur. Many of them are geophytes.
Go to the figure number 2 Fig. 2. Examples of xerophytic vegetation types in the south-west Madagascar (according to Keraudren, 1961). The Hatokaliotsy type resembles most the type A). Among others, Adansonia za (Bignoniaceae) and endemic Alluaudia montagnacii (Didiereaceae) are conspicuous in Hatokaliotsy. 
A. Xerophytic vegetation on limestone 
B. Xerophytic vegetation on sandy sediments 
(similar types as B. are found on the coast near Hatokaliotsy) 
1. Alluaudia dumosa (Didiereaceae), 2. Kalanchoe beharensis (Crassulaceae), 3. Psiadia altissima (Composita), 4. Euphorbia plagiantha (Euphorbiaceae), 5. Aloe divaricata (Liliaceae), 6. Alluaudia adscendens (Didiereaceae), 7. Xerosicyos perrieri (Cucurbitaceae), 8. Brachyaria humbertiana (Graminae), 9. Alluaudia humberti (Didiereaceae), 10. Acanthaceae, 11. Pachypodium geayi (Apocynaceae), 12. Alluaudia procera (Didiereaceae), 13. Cynanchum (Asclepiadaceae), 14. Croton (Euphorbiaceae), 15. Vitis (Vitaceae), 16. Mimosaceae, 17. Didierea madagascariensis (Didiereaceae), 18. Eragrostis biflora (Graminae), 19. Salvadora angustifolia (Salvadoraceae), 20. Euphorbia stenoclada (Euphorbiaceae), 21. Commiphora (Bursaceae), 22. Maerua (Capparidaceae), 23. Hipocrataceae, 24. Stereospermum nematocarpum (Bignoniaceae). 
1. 2. Hatokaliotsy

Hatokaliotsy with an area of 21,850 ha is located in the south-west of Madagascar (see figure 3) along the sea coast. M. E. Nicoll and O. Langrand (1989) classify it as a „biologically interesting place“. In 1956 Hatokaliotsy was proposed for a special reserve (reserve special), but up to now the status have not been confirmed by the Malagasy government. One of the reasons why this status could not have been granted is complete absence of biological information describing the area, as no research have been carried out so far. The only faunistic list, unfortunately very incomplete, mentions only birds and a few species of reptiles and mammals. Floristic information on Hatokaliotsy does not exist. At the same time, no ecological research have been published.
Hatokaliotsy is located on the Mahafaly plateau, its altitude oscilating between 55 and 258 m above sea level. The Mahafaly plateau consists of limestone, and has a karst character. Its western border, parallel to the sea shoreline, is delimited by vast escarpment. The shoreline zone differs very much from the Hatokaliotsy area in many ecological aspects. All Hatokaliotsy can be certainly described as a subarid zone. Eastwards the vegetation character changes from the typical spiny bush (see further) to secondary (man-made) savanna communities. Many karstic phenomena can be seen in the area.
The human population in the area is minimal. There is no permanent village in Hatokaliotsy, only along the western border are several villages with tens to hundreds of inhabitants. The biggest village is Itampolo near the south-west part of Hatokaliotsy, with scattered population of approx. 2,500 inhabitants (see figure 4).
Go to the figure number 3 Fig. 3. Map of Hatokaliotsy as defined by Nicoll and Langrand (1989). The exact position can be delimited by 24° 24´ – 24° 39´ southern latitude and 43° 52´ – 44° 04´ eastern longitude. 
2. Methods

The field research programme called „Hatokaliotsy Project“ was started in 1993. The authors worked in the area in February and March. Regarding difficult accesibility of the inner parts of Hatokaliotsy the work was limited to reconnaissance and basic faunistic and floristic research. According to individual authors’ specializations the lists of the following organisms were worked out: reptiles, selected taxa of invertebrates (Cassinidae, Cerambycidae, Scarabeidae, Scorpionida), succulent plants, and to certain extent also other vascular plants – see tables in chapter 3.1.
This was the first of the series of expeditions to be carried out. Their aim is a complex research of the Hatokaliotsy area as support and accelerate the declaration of the special reserve by the Malagasy government. Hatokaliotsy is a considerably large area with comparatively undamaged and unique communities of so-called „spiny bush“ or „bush épineux“ in French. The research to be carried out in 1996 will include more detailed ecological mapping:
 - complete the lists of species
 - transects and following phytosociological studies
 - quantitative methods of collecting invertebrates and following evaluation of specific composition and abundancy in  some species
 - enable participation of mammalologists and ornithologists
 

3. RESULTS

3.1. Faunistic and floristic records

The following floristic records are the first published lists of succulent plant species occuring in Hatokaliotsy. Most of the species are found in other area in south-west Madagascar. Alluaudia montagnacii is probably endemic for Hatokaliotsy.
The faunistic records of reptiles is partially based on Nicoll and Langrand (1989), containing 1 species, and the records of some other authors, which are nevertheless related to all south-west Madagascar, and not only to Hatokaliotsy. Among the records the discovery of Phelsuma breviceps should be stressed, as is it known only in a few specimens found in other parts of south-west Madagascar. The habitat characteristics are in some aspects different from other known localities. One species can be most probably considered a new species, and was preliminarily classified to belong to Paroedura genus.
Faunistic records of some groups of invertebrates is published for the first time not only for Hatokaliotsy, but also for all arid part of south-west Madagascar.
 
 
 

Tab. I. Succulent plant species reported from south-west Madagascar (previous literary data) and found by the authors (confirmed in 1993). The upper part of the table contains complete list of succulent plant species known from the adjacent areas. The lower part shows selected important species of xerophytic flora.
 
Species Family prev. lit. data confirmed in 1993
Didierea trollii Capuron et Rauh Didiereaceae
Didierea madagascariensis H. Bailon Didiereaceae + +
Aloe vaombe Decorse Liliacaea
Aloe divaricata Bgr. Liliacaea
Aloe rauhi Reyn. Liliacaea
Alluaudia montagnaci Rauh Didiereaceae +
Alluaudia comosa Drake Didiereaceae +
Alluaudia ascendens Drake Didiereaceae
Euphorbia intisi Drake Euphorbiaceae + +
Euphorbia stenoclada Baill. Euphorbiaceae + +
Euphorbia oncoclada Drake Euphorbiaceae + +
Euphorbia tulearensis Rauh Euphorbiaceae
Euphorbia cylindrifolia Marn.-Lap. et Rauh Euphorbiaceae
Euphorbia enterophora Drake Euphorbiaceae
Euphorbia plagiantha Drake Euphorbiaceae
Euphorbia aff millii Drake Euphorbiaceae
Euphorbia croizatii Léandri Euphorbiaceae
Euphorbia delphinensis Ursch et Léandri Euphorbiaceae + +
Euphorbia leucodendron Drake Euphorbiaceae
Alluaudiopsis fiherensis Humb. et Choux Didiereacea +
Turraea sp.  Orchideaceae +
Iamellea sp. Orchideaceae +
Cryptostegia madagascariensis Bojer Asclepiadaceae
Commiphora sp. Burseraceae + +
Kalanchoe beharensis Drake Crassulaceae + +
Kalanchoe grandidieri Baill. Crassulaceae
Kalanchoe arborescenc H. Humb. Crassulaceae +
Xerosicyos danguyi H. Humb Cucurbitaceae +
Stapelianthus madagascariensis (Chaux) Choux Asclepiadaceae
Stapelianthus insignis B. Desc. Asclepiadaceae
Folotsia sp. Asclepiadaceae +
Cynanchum sp. Asclepiadaceae + +
Moringa drouhardii Jum. Moringaceae + +
Megistostegium perrieri  Malvaceae +
Adansonia fony H. Baill. Bombacaceae + +
Adansonia za H. Baill. Bombacaceae + +
Adansonia madagascariensis H. Baill. Bombacaceae +
Delonix adansonioides Leguminaceae +
Xerophyta sp. Velloziaceae + +
Uapaca bojeri Euphorbiaceae +
Tamarindus indica Caesalpiniaceae
Stapelianthus keraudrenae Asclepiadaceae +
Solanum sp. Solanacaea + +
Xerophyta pinnifolia Velloziaceae + +
Grewia sp. Tiliaceae +
Lochnera rosea (L.) G. Don Apocynaceae +
Pachypodium geayi Cost. et Bois Apocynaceae + +
Operculicarya decaryi Anacardiaceae + +
Selaginella nivea L. Selaginellaceae + +
 
 
 

Tab. II. Presence of reptiles in Hatokaliotsy
 
Species prev. lit.  
data
confirmed  
in 1993
remarks
Crocodylus niloticus Laurenti, 1768 According to unverified information by locals present in the upper part of the river Onilahy 
Pelomedusa subrufa (Lacépéde, 1788) +
Pelusios castanoides Hewitt, 1931 +
Pyxis arachnoides Bell, 1827 + Confirmed near Hatokaliotsy, presence in Hatokaliotsy very probable 
Geochelone radiata (Shaw, 1802) + + In Hatokaliotsy frequent 
Hemidactylus mabouia (Moreau de Jones, 1818) + Introduced species. Synanthropic, presence in Hat. not probable 
Paroedura pictus (Peters, 1854) +
Paroedura bastardi (Mocquar, 1900) +
Paroedura sp. nov. + Species nova discovered by the authors 
Phelsuma standingi Methuen et Hewitt, 1913 +
Phelsuma breviceps Boettger, 1894 + Rare species, known only in several specimens. In Hat. first report 
Phelsuma leiogaster Mertens, 1973 +
Phelsuma mutabilis (Grandidier, 1869) + Presence in Hatokaliotsy probable
Furcifer lateralis (Gray, 1831) + +
Chalarodon madagascariensis Peters, 1854 + +
Oplurus cyclurus (Merren, 1820) + +
Oplurus saxicola Grandidier, 1869 + Presence in Hatokaliotsy probable
Oplurus quadrimaculatus C. et A. Duméril, 1851 + Presence in Hatokaliotsy probable
Tracheloptychus madagascariensis Peters, 1854 + Presence in Hatokaliotsy probable
Zonosaurus karsteni (Grandidier, 1869) + +
Zonosaurus quadrilineatus (Grandidier, 1867) +
Mabuya aureopunctata (Grandidier, 1867) + +
Acrantophis dumerili Jan, 1860 + Presence in Hatokaliotsy probable
Sanzinia madagascariensis Duméril et Bibron, 1844 Presence in SW Madagascar doubtful. Reported from the Toliara province by Guibé (1958) without details 
Mimophis mahfalensis (Grandidier, 1867) + +
Mimophis meridionalis Domergue, 1987 + Presence in Hatokaliotsy possible
Mimophis ocellatus Domergue, 1987 + Presence in Hatokaliotsy possible
Leioheterodon modestus (Guenther, 1863) + Presence in Hatokaliotsy possible
Leioheterodon geayi Mocquard, 1905 + Presence in Hatokaliotsy possible
 
 
 

Tab. III. Selected groups of invertebrates and their presence in Hatokaliotsy (only species found by the autors in Hatokaliotsy)
 
Species Group prev. lit.  
data
confirmed  
in 1993
Opisthacanthus madagascariensis Kraepelin, 1894 Scorpionida + +
Scarabaeus radama Scarabaeidae s. lat. + +
Onthophagus elegans Klug, 1832 Scarabaeidae s. lat. + +
Onthophagus catta F., 1787 Scarabaeidae s. lat. +
Helictopleurus quadripunctatus Scarabaeidae s. lat. + +
Glaresis franzi Paulian, 1981 Trogidae +
Phaeochrous madagascariensis Westwood, 1846 Hybosoridae +
Kuijtenous laeviceps (Faim.), 1893 Hybosoridae +
Notosacantha sp. Cassidinae +
Cassida sp. Cassidinae +
Aspidimorpha madagascariensis Boheman, 1854 Cassidinae +
Androya longula Faim., 1901 Cassidinae + +
Androya rubrocostata Fairm., 1898 Cassidinae + +
Coptops liturata Klug, 1833 Cerambycidae + +
Ancylonotus tribulus Fairm., 1895 Cerambycidae + +
Lasiocercis semiarcuata Breuning, 1957 Cerambycidae +
Trachyliopus forticornis Fairm., 1901 Cerambycidae +
Megalofrea decorsei Fairm., 1901 Cerambycidae +
Lentalius dorsopictus Fairm., 1902 Cerambycidae +
Diadelia sp. Cerambycidae +
Macrotoma androyana Fairm., 1890 Cerambycidae +
Hoplioderes aquilus Coquerel, 1859 Cerambycidae + +
Lycoreus sp. Elateridae + +
Cicindela cristipennis Cicindelidae + +
Cicindela andriana Cicindelidae + +
 

3.  2. The human influence in Hatokaliotsy

Regarding the above-mentioned considerations about the nature reserve declaration in Hatokaliotsy the topics on human – nature relation are highly important aspects. The growing population and increasing „civilization“ are the only threats to the nature in Hatokaliotsy.
Practically all the south-western Madagascar is difficult to reach, with exception of several very bad roads. The population is very scarce and the villages are mostly only small groups of straw huts. Local people are small farmers (raising cattle, growing several crops) or fishermen. Any mechanization or industry is missing. From these reasons the area is not touristically attractive, and therefore this form of nature destruction is negligible.
Go to the figure number 4 Fig. 4. The numbers of inhabitants near Hatokaliotsy and their distribution in the landscape (according to Battistini, 1964a and Battistini, 1964b). Many people change their place of stay throughout the year according to seasonal cattle migration. 
The only endangering factor to the nature present themselves the local inhabitants, which nevertheless has several serious trends:
1. Production of charcoal – probably the most serious threat to local biotopes. Good quality wood is rare in the spiny bush, and therefore many rare and even endemic species are felled for the charcoal production. The everyday use of charcoal is typical for all Madagascar, and the production of charcoal is enormous. Villagers in the area have very limited sources of sweet water, and they have to buy it from the truck drivers passing by. Their only „currency“ to offer is charcoal. The most threatened species are the slow-growing Didiereas and Alluaudias, and local people are obviously not aware that these are protected species. Even if they knew, they would not willingly abandon the most important source of their income.
2. Cattle grazing – the head numbers are lower compared with the rest of Madagascar, but regarding low rainfall increases its influence. The cattle consumes a lot of sweet water, which could be used by man. This fact increases indirectly the production of charcoal. According to local tradition the number of heads determines the position of a farmer in the society, and therefore they mostly keep more animal than they need.
During the year seasonal migration of herds occur, and the shepherds move from the sea shore to the inland during the rainy season (Battistini, 1964a). Sertain areas have already been seriously devastated. An example is the village Beheloka (70 km north of Hatokaliotsy), where the original stand of spiny bush have been completely destroyed, and savanna plant communities took its place. The only phanerophyte is Euphorbia stenoclada remaining due to its toxicity. Cattle grazing can be considered as reducing the ecosystems to secondary stands with low abundancy of species.
3. Trade with animals – although the tourist activities in this area is low, those who come are mostly nature lovers or directly trafficants with animals. For some rare animal and plant species this trade presents a considerable danger.
4. Introduction of new species – can be divided into introduction synanthropic animals and introduction of new crops and weeds. Regarding low population density the synanthropic rodents and insects are not a serious threat, and have not been reported directly in Hatokaliotsy. More dangerous are escaped crops (e.g. Agave americana, Agave sisalana, Opuntia aff. ficus-indica). The competition from local plants is lessened by grazing domestic animals, and they grow without their natural enemies. In the border areas of Hatokaliotsy these plants have already overgrown original stands. Fortunately, local people for some unknown reason do not like them, and sometimes burn them, and so these plants present some danger only in marginal areas.
5. Disturbance of water regime – occurs in the inhabitated places. Hatokaliotsy appears to be out of actual danger.

4. Conclusion

Hatokaliotsy is a unique area, where the original plant and animal communities have been conserved up to the present. But the human population increases steadily and their activities are widening. The direct human pressure are seen only in the border areas. For the future it should be declared a nature reserve to stop the expansion of local people. The borders of Hatokaliotsy delimited by Nicoll and Langrand satisfactory. The coastal zone is different from the plateau area, and is much more densely populated. We do not recommend to include it to the reserve, as it has been more influenced by human activities, and it should be left for reasonable agricultural use. The more problematic situation is in eastern border, where the spiny bush gradually changes into secondary savanna. Here the border should be watched and the free entrance of cattle to Hatokaliotsy prevented. Also a buffer zone minimizing the influence of degraded ecosystems to Hatokaliotsy itself should be established. The future Hatokaliotsy special reserve would be with recent Tsinamampetsotsa the only reserves protecting the unique spiny bush ecosystems.
 
 

Literature:

Albertin L., a kol., 1992: Madagaskar: Mensch und Natur im Konflikt. Birkhäuser Verlag, Basel – Boston – Berlin
Battistini R., 1964a: Étude géomorphologique de l´extréme sud de Madagascar, Cujas edit., Paris: 636 pp
Battistini R., 1964b: Geographie humaine de la plaine cotiere mahafaly (These complementaire de Doctorat publie), Cujas edit., Paris: 197 pp
Battistini R., Richard-Vindard G., 1972: Biogeography and Ecology in Madagascar, W. Junk, The Hague: 766 pp
Breuning S., 1957: Faune de Madagascar 4, Insectes (Coleopteres Cerambycidae, Lamiinae) Museum National d´Histoire Naturelle, 400 pp
Eisenberg J. F., Gould E., 1970 The Tenrecs: A study in Mammalian Bahavior and Evolution. Smithsonian Institution Press, Washington
Glaw F., Vences M. (eds.), 1992: A Fieldguide to the Amphibians and Reptiles of Madagascar, Köln
Guibé J., 1958: Les Serpents de Madagascar, Mem. Inst. Sci. Madagascar A/12: 189 – 260
Jacobsen H., 1983: Das Sukkulentenlexikon, VEB Gustav Fischer Verlag, Jena
Jenkins M. D. (ed.), 1987: Madagascar: An Environmental Profile, IUCN, UNEP, WWF, Gland and Cambridge
Jolly A., Oberlé Ph., Albignac R., 1984: Key Environments Madagascar, Pergamon Press
Keraudren M., 1961: Quelques aspects des formations xérophiles du sud de la République Malgache, Bull. Soc. Bot. Fr. 108/1 – 2: 73  – 79
Koechlin J., 1972: Flora and vegetation of Madagascar. in: Battistini R., Richard-Vindard G.: Biogeography and Ecology in Madagascar, W. Junk, The Hague
Mittermeier R. A., Rakotovao L. H., Randrianasolo V., Sterling E. J., Devitre D., 1985: Priorités en matiere de conservation des especes a Madagascar,  UNEP, UICN, WWF, Gland
Nicoll M., Langrand O., 1989: Revue de la conservation et des aires protégées, WWF Gland, Suisse
Paulian R., Lebis E., 1960: Faune de Madagascar 11, Insectes, Coleopteres, Scarabaeidae (Scarabaeina, Ontophagini, et Helictopleurina), Museum National d´Histoire Naturelle, Paris: 130 pp
Paulian R., 1961: Faune de Madagascar 13, La zoogéographie de Madagascar et des iles voisines, Museum National d´Histoire Naturelle, Paris: 484 pp
Paulian R., 1981: Faune de Madagascar 56, Insectes Coleopteres Trogidae et Hybosoridae, Museum National d´Histoire Naturelle, Paris: 28 pp
Quentin R. M., Villiers A., 1975: Faune de Madagascar 40, Insectes, Coleopteres, Cerambycidae, Parandrinae et Prioninae, Museum National d´Histoire Naturelle, Paris
Rabinowitz P. D., Coffin M. F., Falvey D., 1983: The separation of Madagascar and Africa, Science 220: 67 – 69
Rakotovao L., Barre V., Sayer J., 1988: L’Equilibre des Ecosystemes forestiers a Madagascar, UICN Gland Suisse et Cambridge
Rauh W., 1975: The Didiereaceae, Ashingtonia 2: 2 – 5
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Acknowledgements:

The authors would like to express their gratitude to the employees of local WWF office, particularly Mrs. Sheila O’Connor and Mr. Olivier Langrand for precious suggestions concerning ecological field work in extreme conditions of south-west Madagascar.
We thank to Mr. and Mrs. Rasoloson for their help in orientation in local legal and social conditions.
We also thank to Mrs. J. Rivert, Mr. A. Domerque and many others, who supported our work and whose help was of immense value
We are deeply indebted to Air Madagascar for financial help and moral support. Our further sponsors were:
  – Česká spořitelna (The Czech Savings Bank), branch Ústí nad Labem
  – SWAH Ltd.
  – Investiční banka Ttd., branch Ústí nad Labem
  – Koktejl magazine
  – Ekoagrobanka
  – IPARS Comp. constructions
  – Česká pojišťovna (Czech Insurance Comp.), branch Ústí nad Labem
  – Made in Switzerland Trade Comp.
  – SLUNCE Ltd. advertizing
All these companies deserve our deep gratitude
 



 
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