4 The protected areas and biosphere reserves in the savannahs.
1.1 General considerations
Unlike the tropical rainforests, the savannahs do not contain unusually high biodiversity. They are famous, however, for their easily seen wildlife. In a forest containing more than a thousand species of birds, the bird-watcher will be lucky to see more than a hundred species on a morning walk. Such is not the case in the savannahs. A large number and variety of large mammals can be seen in Africa's grassy and woody savannahs, opportunities for birdwatching are excellent in the woody savannahs of southeast Asia, and in the New World tropical savannahs it is relatively easy to see large felines such as jaguars and other large mammals such as giant anteaters.
Yet the world's woody and grassy savannahs are at great risk. The main causes for savannah loss are desertification, fires, and transformation into grazing. Climatic change threatens the entire planet, but many savannah regions, especially the Sahel in Africa, are among the most intensely affected. As the climate becomes hotter and drier, the woody savannahs turn into grassy savannahs or scrubs, and both may eventually become deserts.
The development of protection in the savannah areas
Many of the protected areas in the savannahs, especially the larger ones in Africa, were created in the early twentieth century by the colonial powers as game reserves or wildlife reserves. The Amboseli National Park (Kenya) is the remains of the southern hunting reserve created by the British administration of the Eastern African Protectorate in 1906, which occupied 107,000 [mi.sup.2] (277,000 [km.sup.2]). In the same region, the Selous Game Reserve (19,300 [mi.sup.2] [50,000 [km.sup.2]]) and the Serengeti National Park (5,800 [mi.sup.2] [15,000 [km.sup.2]]) in Tanzania were created in 1922 and 1951, respectively. The Tsavo National Park in Kenya (7,700 [mi.sup.2] [20,000 km2]) was created to the east in 1948.
Since the end of the 1970s, views on protected areas have changed significantly, and these changes have had several important effects on human activities. In the first place, the idea of the strict protection of the national parks and hunting reserves has been replaced by the idea of a compromise, trading protection for resource use. Secondly, the currently protected areas are considered much less as "islands," and great efforts are made to involve the local communities in their management and to study the areas surrounding them. The concept of the biosphere reserve is a result of precisely this line of thinking. The protected areas of savannah are thus starting to be seen more as elements forming part of national and international savannah systems. A single area is often not enough to protect large mammal populations effectively; it is often necessary to protect migratory corridors and ensure access to water holes during the dry season to ensure the safety of certain species. In Botswana, for example, fencing in the middle of the savannah prevents wild animals grazing with livestock but also interferes with the migration of gnus.
The protected areas of savannah may also generate a series of goods and services. Wild animals are often a key source of protein for local communities. They also provide skins for clothing and horns, teeth, and nails for a variety of uses. Plants provide food, wood, straw, and other resources for the native communities. Protected areas sometimes contain important cultural artifacts like the monoliths on Komodo Island or the cave paintings in Boucle de Baoule. In many regions, the surrounding lands have been so degraded by human populations that the protected areas are the only source of plant and animal resources. It is thus important for agreement to be reached between the park's managers and the local population to ensure the sustainable use of these products. Some southern African parks allow the local population, under strict control, to extract wood and to hunt a number of animals. In Zambia and Botswana, the Hunting Department and the local communities cooperate so closely in the administration of the hunting management areas that the rural wardens are chosen by the local population, and the wildlife is protected almost exclusively by the local communities.
Some protected areas in the savannahs have become major sources of tourist income. Brazil, Venezuela, Kenya, Tanzania, Namibia, Zambia, India, and Cape York (Australia) show great potential for development of savannah-related tourism. Ecotourism has been practiced for some time in Kenya and Tanzania, and areas like the Amboseli, Serengeti, and Tsavo National Parks are among eastern Africa's best-known tourist attractions. These parks and other experiences offer some lessons for other countries on how to develop ecotourism in their protected savannah areas. One of the main problems is to ensure that profits from tourism are reinvested in the system of protected areas and are not channeled to central government or the private sector. The benefits of ecotourism should also help to develop local economies, so that the communities within or near protected areas can appreciate their economic value.
Management problems in protected savannahs
The savannahs are a classic example of a nonequilibrium system and, as such, their behavior is unlike that of a system in equilibrium. There is no reason why they should return to their initial state after removing the source of a disturbance, and they may oscillate indefinitely between different states in virtue of their own internal dynamics or external disturbances. This means that there is no single set of management instructions on how to manage a protected savannah and no clearly defined model for the correct use of savannah resources. The lack of clear aims and the consequent lack of management plans further complicates things. In countries with savannahs, resources are usually scarce and labor availability and management structure is often deficient. In the end, it is the limited intervention capacity that, together with the preceding history and disturbance regime, really determines both management aims and results.
In many protected areas of savannah, humans have played an important role for thousands of years in maintaining the savannah ecosystems by burning. The human populations of most protected areas have in fact declined greatly, and management of a protected area requires systematic burning to maintain the savannah in good condition. In the absence of this type of interference, the savannah ecosystems tend towards a dry forest climax. Once this has been established, it is difficult to recover the original savannahs and impossible to reproduce the original species composition. Fire is one of the most powerful tools available to the managers of protected savannah areas, but it has to be used with great caution so as not to provoke long-term changes in the biomass, species composition, and productivity. The frequency and timing of burning are very important. For example, burning at the beginning of the season, together with a failure of the rains, may increase the risk of erosion and reduce the grazing. However, the suppression of fires may also have similar effects. Fire is also important in maintaining the tourism and landscape interest.
The savannahs, especially the woody ones, accumulate a large quantity of organic matter, and because rainfall is scarce they are at great risk of fires, whether spontaneous or due to negligence or criminality. Constant control of undesired fires is necessary. A different approach is required in small protected areas with easy access and in large areas where mobility is harder. In small easily accessible areas, park wardens can patrol regularly to put out small fires before they turn into large ones. In large areas, fire has to be fought with periodic controlled fires. This is based on the fact that regular fires do not generate very high temperatures; most trees and grasses can survive the short period of high temperatures while the fire passes. Controlled burning should be carried out by experts able to judge the force and duration of the wind required to burn precisely the area necessary, without damaging neighboring areas or causing wildfires. This technique can also be used to stop the advance of natural fires by burning its source of fuel before the fire arrives (counterfires).
Culling the weakest animals from the herbivore populations is another management tool frequently used to prevent irreversible damage to savannah ecosystems by overgrazing (the reason why the number of ungulates has to be controlled). The selection has to be carried out with great care, and the effects on the vegetation have to be monitored closely. Weak animals should be culled at a moment that does not coincide with adverse environmental conditions, as it might lead to serious losses among the species being culled.
In most of the African savannahs, however, poaching is the main problem facing the managers of protected areas. Human beings have hunted large mammals for their flesh and skins ever since they entered the savannahs, but recently the problem of abusive hunting has arisen in the hunting of certain species for secondary products, including furs, claws, teeth, tusks, and horns for jewelry and medicine. Two of the animals most affected by international trade in secondary products have been the African elephant (Loxodonta africana) and the rhinoceroses (Diceros bicornis and Ceratotherium simum). The ivory problem is very complex and beyond the influence of the managers of protected areas. There is still no consensus on the best way to control this trade; some people are in favor of totally prohibiting all trade in ivory objects, while others would prefer the ivory trade be legalized so it can be managed sustainably. Many possible solutions have also been suggested to reduce the impact of the rhinoceros horn trade on rhinoceros populations.
Human invasion and colonization are serious threats facing many protected areas in the African savannahs. Some parks, especially Serengeti and Amboseli, have shrunk due to the invasion of human settlements. In the New World tropics, many areas of woody savannah, like many forests and rainforests, have been turned into grasslands. The existing vegetation is easy to eliminate, and in general the soils are unsuitable for agriculture, so very low-density cattle ranching has been an attractive alternative, but it is unsustainable in the long term.
1.2 Protected parks and areas
The tropical savannahs occupy more than 7,720,000 [mi.sup.2] (20 million [km.sup.2]). More than 425,000 [mi.sup.2] (1.1 million [km.sup.2]), roughly 5.5%, is specifically protected, making the savannah one of the biomes with the most protected area, both in relative and absolute terms. This is due mainly to the large size of the protected spaces. The average size of the parks in the savannah is 1,400 [mi.sup.2] (3,600 [km.sup.2]), though some protected parks and areas exceed 3,900 [mi.sup.2] (10,000 [km.sup.2]).
The parks in the African and South American savannah
The protected areas of the African savannah need to be large to protect viable populations of large herbivores such as the gnus (Connochaetes) and the large predators such as lions (Panthera leo). Furthermore, they often have to protect migratory routes and shelters for the dry season to ensure the animals' survival. This is the case of the eastern Tsavo National Park (Kenya) and the Serengeti National Park and Selous Fauna Reserve (Tanzania).
The protected areas of savannah in South America are also very large. The El Tuparro Nature Reserve (Colombia) occupies 5,000 km2 of grassy savannahs in the Orinoco region. The Canaima National Park protects 30,000 km2 of the Guyana Shield in Venezuela and is mostly occupied by the broad savannahs of the plateau known as the Gran Sabana (Great Savannah). Yet the woody savannahs and the secondary formations derived from monsoon forests (see volume 2, p. 429) in South America have been relatively ignored. Awareness is now growing of the value of these forests (which have been shown to possess almost as much biodiversity as their wetter equivalents); still, they are disappearing fast. Only 2% of the original 550,000 km2 of dry forest in Central America remains and only 0.08% of this area is protected. Some Central American countries are now reassessing the size of their protected areas and are trying to incorporate more areas of dry forest. Pilot projects in the Guanacaste National Park (Costa Rica) have even managed to regenerate dry forest from grasslands.
The parks in Asia's savannahs
The savannahs of southeast Asia are harder to define than those of the other continents and contain very few protected areas and biosphere reserves. The generally dense human populations would make it hard for protected areas to survive. The inhabitants of the areas around the sanctuaries, parks, and forest reserves are often obliged to extract basic resources from them--firewood, building materials, meat, and grazing for their herds--as these resources are increasingly scarce in other areas. Some protected areas in the region have been invaded by colonists and have been altered by the traditional shifting agriculture practices. High livestock density often complicates the situation, as herders are increasingly forced to go farther and farther into the protected areas to find grazing and water. The farmers and stockraisers on the edges of protected areas often lose livestock to the attacks of predators, and their recently sown crops may also be damaged.
Effectively protected areas are shrinking and are increasingly isolated from each other; few are large enough to support populations of large mammals. Yet in many areas of southern and southeastern Asia, these animals would probably be unable to survive outside protected areas. Only smaller and more adaptable animals, including the wild boar (Sus scrofa), the sambar deer (Cervus unicolor), muntjak deer (Muntiacus muntjak), chevrotains or mouse-deer (Tragulus), and several primates, are sure to survive without special measures to protect their habitats. The survival of many rare species could be ensured by improving the management of the existing protected spaces, but the fact that they are often small and fragmented creates a series of distinctive problems. Excessively small, protected areas tend to become islands surrounded by a humanized landscape and eventually are unable to support as many species as the larger areas. Many parks and reserves contain species that have arrived from elsewhere, sometimes in large enough numbers to have a negative impact on natural systems. Poaching, especially of rhinoceroses (Rhinoceros, Dicerorhinus), Indian elephants (Elephas maximus), and tigers (Panthera tigris), is a major management problem in most of the region. The rhinoceros populations have been virtually exterminated throughout almost all of their former range. There is a prosperous regional trade in birds, freshwater fish, and plants, and the protected areas may become centers of illegal supply. The logging and smuggling of valuable hardwoods is an equally serious problem. In some regions, political instability has hindered park management, and the protected areas are often used as shelters by insurgents.
Even so, some protected spaces in the Asiatic savannahs are quite successful. Part of the Gir National Park and Wildlife Sanctuary in Gujarat (India), where the last families of lions in Asia live (see volume 2, p. 481), is in the savannah, as is the Komodo National Park and Biosphere Reserve (see volume 2, pp. 496-498). In addition to these spaces, there is the Manas Wildlife Sanctuary on the India-Bhutan border and the Shwesettaw Nature Sanctuary in Myanmar.
The Manas Wildlife Sanctuary
Manas Sanctuary covers 39,100 ha of the 283,700 ha of the Manas Tiger Reserve in Assam State, northeastern India (1 ha=2.5 acres). The sanctuary includes part of the valley of the Manas River, which has its source in Bhutan, and is on the Bhutan frontier abutting the Manas National Park in Bhutan (65,800 ha). In 1974 Bhutan and India reached an agreement on the joint management of the two sanctuaries, whose unique biological importance led to their inclusion on the World Heritage List in 1985.
Manas is located in the foothills of the Outer Himalayas and includes a wide range of habitats, from mountainous jungle in the north to open savannah in the south. The area is mainly flat lowland with great alluvial terraces. The southeast monsoon dominates the climate, and annual rainfall is about 3,000 mm. Temperatures vary between 4-37[degrees]C.
Manas Sanctuary's extraordinarily diverse flora and fauna cannot be compared to that of anywhere else in India. There are more than 540 species of plants. There are three main vegetation types: the mixed wet deciduous forests of the eastern Himalayas, common to the lower areas; the tropical semievergreen forests on the well-drained soils on hills below 2,493 ft (760 m); and the large grasslands in the west of the sanctuary, dominated by wild sugar cane (Saccharum spontaneum), wire-leaved sugar cane (S. filifolius), and cogon grass (Imperata cylindrica). The grasslands contain scattered trees and shrubs such as black catechu acacia and shisham (Dalbergia sissoo). The highland savannahs are different from those of the wet alluvial savannahs, and between them cover almost 50% of the sanctuary.
The sanctuary is home to 55 species of mammal, 22 of them in danger of extinction (more than any other protected area in India). These include the entire population of the endemic golden langur monkey (Trachypithecus geei), the dwarf pig (Sus salvanius), and the Assam rabbit or hispid hare (Caprolagus hispidus). The other mammals include the capped langur monkey (Presbytis pileata), the clouded leopard (Neofelis nebulosa), tiger (Panthera tigris), leopard (P. pardus), four species of wild cat (Felis bengalensis, F. marmorata, F. temminckii, and F. viverrina Balso known as the leopard cat, the marbled cat, Temminck's cat, and the fishing cat), the binturong (Arctitis binturong), the blubberlipped bear (Ursus ursinus), dhole (Cuon alpinus), gangetic dolphin or susu (Platanista gangetica), Indian elephant (Elephas maximus), the barasinga or swamp deer (Cervus duvauceli), the last pure strain stock of water buffalo (Bubalus bubalis arnee), and the gaur (Bos gaurus). Until recently, Manas was the home of the third largest population of one-horned Indian rhinoceros (Rhinoceros unicornis) in India, but poaching has exterminated the local population. More than 300 species of birds have been identified in the park, including the Bengal florican (Houbaropsis bengalensis). The tortoise Kachuga sylhetensis was rediscovered in 1988, a century after the last sighting.
Manas is surrounded by human settlements with their different patterns of land use. These include the village of the Bodo tribe, Nepalese stockraisers, as well as Bengali and Assamese farmers, about 59,000 of whom live in 146 villages in a peripheral protected area of the tiger reserve. About 50 villages are near the park's core area, where human population density may reach 600 people/km2. There is poaching of elephants and rhinoceroses and illegal logging. The Bodo, one-third of the population of Assam, are fighting for a separate state, and since 1989 guerilla groups have been using the park as a shelter and training area. The nearby population takes firewood from the park, as well as building materials, and they lead their livestock there to graze. The World Wide Fund for Nature (WWF) has started a project to identify the basic needs of the population living near the park, with the long-term aim of providing alternatives to their current dependence on the park and to obtain their cooperation in its protection and management. As a consequence of the political situation, tourism has virtually disappeared from the area.
The Shwesettaw sanctuary
The Shwesettaw sanctuary in Myanmar lies between the Arakan Mountain Range and the River Irrawaddy, about 261 mi (420 km) north of Rangoon, bordered to the north by the River Mon Chaung and to the south by the River Man Chaung. It includes the Kywetaga, Kyauko, and Shwesettaw Forest Reserves and the Shwesettaw, Kyikan, and Myosapho Protected Forests. The sanctuary covers a total area of more than 55,000 ha (1 ha=2.5 acres) at an elevation of between 328-1,837 ft (100-560 m) and was created in 1940, basically to preserve a population of 350 brow-antlered deer (Cervus eldi).
The central and eastern sectors of the system are smooth rolling hills and ranges, while in the west, the higher sandstone ranges are separated by wide valleys. Several seasonal watercourses cross the region, which receives average annual rainfall of about 35 in (900 mm), mainly between May and November. Temperatures vary from 4-43[degrees]C.
Most of the sanctuary, mainly the lowland areas, is covered by a dry, grassy savannah vegetation known as indaing, adapted to fire (pyroclimax), with scattered and twisted specimens of dipterocarps (Dipterocar-pus), ingyin (Shorea siamensis), and thitya (S. oblongifolia). The eastern slopes support a taller mixed deciduous forest of teak (Tectona grandis), pyinkado (Xylia dolabriformis), and black catechu (Acacia catechu), with a variable understory of bamboos. There is dry forest dominated by Tectona hamiltoniana in the wetter areas. Large areas of the sanctuary were cultivated, and there is a wide range of seral stages on the succession from grasslands and scrubs.
The sanctuary's more important mammals, in addition to the brow-antlered deer, include the Siamese hare (Lepus peguensis), the Malaysian bear (Ursus malayanus), gaur (Bos gaurus), banteng (B. javanicus), muntjak deer (Muntiacus muntjak), the Indian hog-deer (Cervus porcinus), dhole (Cuon alpinus), leopard (Panthera pardus), wild boar (Sus scrofa), and several species of macaque monkey (Macaca) and langur monkey (Presbytis). Records also include the Himalayan black bear (Ursus thibetanus), sambar (Cervus unicolor), and serow (Capricornis sumatraensis). The brow-antlered deer (Cervus eldi) is definitely the most interesting species, and the estimated population in Shwesettaw is 240 individuals. Outside Myanmar it is effectively extinct, and the only two populations in the country live in protected areas. There are at least two endemic species of birds--the white-throated babbler (Turdoides gularis) and the hooded heron (Crypsirina cucullata)--as well as several species found throughout the region. There is not a single human settlement within the sanctuary, but the eastern half is edged by villages and intensively cultivated land. The sanctuary is widely used by the people of the neighboring villages as a source of firewood, bamboo, and land to grow their crops. When the sanctuary was created, the inhabitants were guaranteed the right of access to almost the entire area. About 45% of the sanctuary is managed as protected forest, where logging is prohibited. The Shwesettaw Pagoda, a religious site of national importance, is next to the southern edge of the site. The main threats to the sanctuary are the intensive and extensive crops within it and around it, the indiscriminate extraction of natural resources, and poaching. The park is patrolled irregularly.
The parks in the savannahs of Australia and New Guinea
Australia and New Guinea's open woody formations are well protected in terms of the proportion of their total area included within the systems of protected areas. Australia has won international praise for its commitment to the ideal of integrated conservation and is recognized as being in the vanguard in its idea of the cooperative management of national parks located in sites that were traditionally common land. In these parks, Aboriginal culture is a basic element of management; it is, in fact, of great importance in the overall concept of national park management in Australia. The Aboriginal parks of Northern Territory include Kakadu, Nitmiluk, Gosse Bluff, Gurig, and Uluru, which is also a biosphere reserve. There are many other, more conventional, parks and protected spaces throughout Australia and in its large areas of savannah.
The protected spaces in New Guinea are not so numerous or adeptly managed, but some are of great interest, among them the Tonda Natural Management area in Papua-New Guinea. Situated at the southwestern tip of Papua-New Guinea and used for many purposes, Tonda consists of a large coastal strip along the Torres Strait and is bordered to the west by the frontier with the Indonesian territory of Irian Jaya and to the east by the River Mai Kussa. It was established in 1976 and is on the southern edge of the Oriomo Plain, a relict alluvial plain that rises 148 ft (45 m) above sea level. The coastline consists of a narrow strip of marshes bordered by low coastal rises, enclosing--on the land side-wetlands formed on marine or estuarine deposits. Three rivers run through the area, all of them slow-flowing, and during the rainy season the tide usually rises for some way up the lower stretches. Annual rainfall is 59-79 in (1,500-2,000 mm).
Tonda's vegetation is very different from that of the rest of New Guinea, essentially because of its highly seasonal climate and the presence of relict Australian floras. Furthermore, its composition and structure are affected by anthropogenic fires and seasonal flooding. Most of the area is covered by one of several types of savannah, though there are other types of primary vegetation. There are mangrove formations all along the coastline, coastal forests and scrub, monsoon forest, gallery forest, mixed flooded forest, and flooded Melaleuca forest; there are also grasslands dominated by cogon grass (Imperata cylindrica) and Pseudo-raphis spinascens, a grass of waterlogged sites; flooded rushbeds with scattered clumps of Pandanus; and aquatic and riverside communities, which survive in the inaccessible areas of rivers and wetlands.
There are different forms of savannah. One is mixed, tall, and very open with a discontinuous tree layer, several species of Acacia, Tristania, Xanthostemon, Melaleuca, and Alstonia up to 82 ft (25 m) tall, and a dense herbaceous layer. Another is a mixed savannah of similar species, but with trees less than 82 ft (25 m) tall. A third is a savannah with a low tree layer dominated by Melaleuca, Dillenia alata, and Tristania suaveolens in seasonally flooded areas. Finally, there is a low monsoon scrub with trees less than 23 ft (7 m) tall on nutrient-poor or badly-drained soils, with species such as Melaleuca viridiflora, Banksia marginata, and Grevillea glauca.
The density of human population in the region is very low, so it has been left largely intact. Hunting, fishing, and egg collection are important parts of the local economy, in addition to the traditional shifting cultivation of yams, taro, and sweet potato practiced in forest areas. The native inhabitants can hunt without restrictions. They hunt using traditional methods and target the agile wallaby (Macropus agilis), the wild boar (Sus scrofa), and the cassowary (Casuarius casuarius). They also earn income from the sale of the skins obtained by hunting the estuarine crocodile (Crocodylus porosus).
The area has been deeply changed by the introduction of the Strait sambar or russa (Cervus timorensis), with a population of at least 20,000 individuals in the Bulla alluvial plains. There are also feraldogs, cats, pigs, and cows. The native mammals include the common echidna (Tachyglossus aculeatus), the agile wallaby (Macropus agilis), scrub wallabies (Thylogale stigmatica, Dorcopsis veterum), rodents, and bats. The birds include the Australian eagle (Aquila audax), red crane (Grus rubicunda), Australian bustard (Ardeotis australis), the bluewinged kookaburra (Dacelo leachi), and some birds endemic to New Guinea. Many waterbirds arrive in the wet season, and during the Northern Hemisphere winter hundreds of thousands of Palaearctic migrants occupy the tidal marshes.
Most of the world's population of lesser curlews (Numenius minutus) are localized in this area. There are also many species of amphibians and reptiles, including the estuarine crocodile (Crocodylus porosus), New Guinea crocodile (C. novaeguineae), three monitor lizards (Varanus), and the Papuan black snake (Pseudechis papuana). Fish are abundant. The highly productive floodable plains are the feeding sites of the catadromous perch (Lates calcarifer). Some freshwater crabs are also common.
Geomorphological, floristic, and faunistic research has shown the zone's importance due to its mixture of the Australian flora and fauna with the species and communities typical of New Guinea. Feral deer and pigs, with their impact on the region's ecology, may have contributed to the invasion of the Bulla plains by trees and scrub.
One of the major problems affecting the area is poaching. Poachers from Irian Jaya set nets at the mouth of the Bensbach River and smuggle crocodile skins over the frontier. This situation is worsened by the fact that the landowners receive little guidance and supervision of their natural resource management, and projects to farm crocodiles, cassowaries, and butterflies have all come to nothing.
The single warder is responsible for the entire area. The visitors to Tonda are mainly hunters, and nature-lovers are obliged to travel with a paid guide. Tourism is centered around the nature hostel in Bensbach, where hunting and angling are organized.
2. The UNESCO biosphere reserves in the savannahs
2.1 The biosphere reserves in the savannahs
Thirty-two biosphere reserves in 22 different countries (15 in Africa, four in the Americas, and two in Asia and Australia) are wholly or partly in the savannahs, two-thirds of them in Africa. Africa also contains most of the larger savannah biosphere reserves, as shown by the fact that almost three-quarters of the total area of biosphere reserves is in Africa, with an average size of more than half a million hectares (1 ha=2.5 acres). The Serengeti-Ngorongoro Biosphere Reserve (Tanzania) covers more than two million ha, while Samba Dia (Senegal), only covers 756 ha. Australia has the most savannah biosphere reserves: three. The other countries either have one (Benin, Bolivia, Burkina Faso, Central African Republic, Colombia, Congo, Guatemala, Indonesia, Ivory Coast, Niger, Mali, and Uganda) or two (Cameroon, Guinea, Kenya, Sen-egal, Sudan, Tanzania, Thailand, and Democratic Republic of Congo).
The first biosphere reserves in the savannah biome, both created in 1976, were the Sakaerat Environmental Research Station (Thailand) and the Luki Forest Reserve Biosphere Reserve (Democratic Republic of Congo). Neither is dominated by savannah, as Sakaerat is dominated by monsoon forest, though there are also open dipterocarp forests comparable to woody savannahs. In Luki, savannah also occupies only a small area, as the site is mainly dominated by tropical rainforest. The most recent incorporations are the Cerrado Biosphere Reserve in Brazil (1993) and the Region "W" du Niger (1996).
2.2 The biosphere reserves in the American savannahs
The four biosphere reserves in the American savannahs are between Guatemala and Bolivia and contain very different types of savannahs--the woody savannahs of the Sierra de las Minas in Guatemala and in the Cerrado Biosphere Reserve in Brazil, and the wet grassy savannahs of the llanos of the Orinoco, or the Mojos, represented respectively in the biosphere reserves by the El Tuparro Nature Reserve in Colombia and the Beni Biological Station in Bolivia.
The Beni Biosphere Reserve
The Biosphere Reserve of the Beni Biological Station is in northeast Bolivia, in the provinces of Ballivian and Yacuma, in the Department of Beni. The 135,000 ha reserve is an area with several different forest types containing huge areas of seasonally flooded savannah on its northeastern and western borders. The foothills of the Andes are 31 mi (50 km) to the southwest. The Beni Reserve is situated in an area of transition between lowland tropical rainforest and subtropical forest. It is the convergence of three biogeographical regions: Amazonia, the Chaco, and the cerrado.
Natural values and features
The influence of these three biogeographical regions leads to a great diversity of habitats, animals, and plants, with more 500 species of bird, eight primates, 40 bats, and more than 100 fish, as well as half of Bolivia's protected animal species.
The two main rivers draining the area are the Maniqui, which marks the western edge of the reserve, and the Curiraba River, which marks the eastern limit. The area is almost flat and shallow lakes form in the badly drained areas during the rainy season from November to March but disappear during the dry season. The Maniqui River has a decisive influence on the area, and its rapid changes of course and speed have given rise to vegetation formations in different stages of succession.
The Beni area has very limited agricultural possibilities due to the poverty of the soils, whose low fertility is related to the seasonal flooding regime. The abundant remains of pre-Columbian civilizations (thousands of drained fields, many channels, terraced riverbanks and mounds) suggest this now depopulated region may have been home to half a million people before the arrival of the Spanish conquistadores, and probably long before them, as there is absolutely no mention of any possible civilization in the region in the chronicles of the time. The entire area of the Beni Biosphere Reserve is state property and is surrounded by privately owned ranches and small farms managed by lowland campesinos. The reserve's core is uninhabited. The Chimane Indians, part of whose territory is within the reserve (about 20%), live mainly on the eastern and western edges, along the banks of the River Curiraba and the River Maniqui.
The Amazonian influence is shown by the presence in the tree layers of the forests of palo Maria (Calophyllum brasiliense, Guttiferae), cedro (Cedrela odorata, Meliaceae), and pachiuba palm (Socratea exorrhiza), and of animals like the southern river otter (Lutra longicaudis) and the sloth Bradypus variegatus. Only 15% of the reserve is occupied by savannahs, and the rest is forests and woodlands. Between the forest and the savannah there is a transition zone with tabijos (Tabebuia spp.), chaaco (Curatella americana, Dilleniaceae), and Pseudobombax spp. The matorral is dominated by Machaerium spp. (Legumi-nosae). The chaco's influence is shown by the presence of plants such as tabijo (Tabebuia spp., Bignoniaceae) and animals such as the huaso or brown brocket deer (Mazama goazoubira) and the nine-banded armadillo (Dasypus novemcinctus). The cerrado contributes plants like the tuseque (Machaerium hirtum, Leguminosae) and chaaco (Curatella americana, Dilleniaceae), also known as mapajo, and animals such as the rhea (Rhea americana) or the maned wolf or borochi (Chrysocyon brachyurus). About 2,000 species of vascular plant have been recorded in the reserve.
The maned wolf (Chrysocyon brachyurus) is more a long-legged fox, with legs like a greyhound. It got its name because of the patch of long black erectile hairs on its nape and shoulders and its large size. It is found in swamps and savannahs in Brazil, although it also occurs in bordering areas of neighboring countries including Bolivia. The maned wolf's tail is very short for a member of the dog family, while its legs are extremely long. Apparently, its stiltlike legs allow it to see over the tall grasses of the savannah, while its large erect ears can detect rodents at a distance. When crossing marshy ground, the maned wolf can spread out the pads of its feet, rather like an otter's webbed feet, so it does not sink.
The giant armadillo (Priodontes maximus) is a typical inhabitant of the Beni Reserve. Though it is tolerant of a range of lowland habitats, including forest, it lives mainly in forest areas or on the forest-savannah edges. It is easily distinguished from other armadillos because it is much bigger and has large scales covering its back, making it the most heavily armored of all modern mammals. The giant armadillo can dig well with its large front claws, both in search of food and to make itself a burrow. Termites are its main food, but other invertebrates, snakes, and carrion are also taken. Snake venom seems to persist in the animal's flesh, as there have been cases of poisoning comparable to snake bites after eating giant armadillo flesh. Its area of distribution is from Central America as far south as northern Argentina and Uruguay. Though its range has not shrunk in recent years, its population has decreased dramatically and the species is now classified as vulnerable by the IUCN.
The marsh deer (Blastocerus dichotomus) is the largest South American deer. Its coat is dull brown in winter, turning a warm russet brown during the summer months, while the legs remain an attractive black throughout the year. The marsh deer is characteristic of wet areas and, like the maned wolf, its digits are linked by an expandable membrane allowing it to walk over marshland. The deer sleeps during the day and emerges at night to feed on grasses, reeds, and other aquatic plants. The marsh deer, unlike other members of its family, does not have a defined breeding season; antlers are grown and shed throughout the year, and the single calf may be born in any month. Recently the number of marsh deer has declined sharply because of overhunting and habitat loss due to agriculture and drainage.
The greater rhea (Rhea americana) is one of the most typical birds of the South American cerrado. Members of this order, the Rheiformes, were already present in the region in the late Paleocene, 55 million years ago. The rhea is very well adapted to terrestrial life, as its very long legs with only three toes allow it to run at speeds of over 37 mph (60 km/h). The rhea's long neck enables it to spot predators such as the jaguar (Panthera onca) from far away in the open savannah. When flushed, the rhea flees at high speed in a zigzag course using its outstretched wings as stabilizers when it changes direction. In the breeding season, the male utters a loud bisyllabic roar resembling a stag's bellow; the onomatopoeic local name, nand, is derived from this call. The rhea eats leaves, fruits, and insects but also takes small mammals and reptiles. Like all birds, it swallows stones to help grind the food in the gizzard. The rhea plays a major role in the regeneration of the cerrado and palm savannah vegetation. It roams over large distances, acting as a seed dispersal agent, and studies have shown that seeds that have passed through the bird's digestive tract are up to three times more likely to germinate than those falling to the ground uneaten. The rhea is gregarious and normally forms large flocks, but in the absence of other rheas, it will seek the company of sheep, cattle, and deer.
The red-legged or crested seriema (Cariama cristata) is another typical cerrado bird, the last of a line of terrestrial predators whose fossil ancestors go back to the Tertiary (50 million years ago). These fossils and those of the rhea show that the open savannahs and other habitats now present in Argentina, Bolivia, Brazil, and Paraguay are an ancient feature of the continent. The seriema is much smaller than the rhea, weighing only 48 oz (1,500 g), but its lifestyle is very similar. It has long legs, can run very fast, and usually runs away from danger, reaching speeds of up to 44 mph (70 km/h), rather than flying away. The seriema's diet is similar to that of the rhea, but it is said to eat so many snakes that they are not found where seriema's hunt. Whether or not this is true, both birds are very useful in controlling agricultural and cattle pests and are encouraged to breed on some ranches.
Management and problems
Most of the human inhabitants of the Beni Bio-sphere Reserve are Chimane Indians, who occupy an area in the transition zone between the humid forest on the eastern foothills of the Andes and the westernmost edge of the Beni savannahs. They are the traditional inhabitants of this part of Bolivia and live mainly on the banks of the Maniqui River and its tributaries; in Beni, in fact, they are on the eastern edge of their traditional hunting grounds. Like most native peoples, they have a strong cultural identity and deep knowledge of their environment. Chimane communities are organized around a core family or groups of families formed by two or three like-minded monogamous couples that function as a social, political, and economic unit.
Fishing is their main source of protein, but they also hunt many animals and gather fruit, medicinal plants, and honey. They use firearms, hooks, and lines to hunt and fish, but when they have no ammunition, they use their traditional bows and arrows. The Chimane's hunting area is centered more on the forests in their territory than in the savannahs. One unresolved problem in the Biosphere Reserve of the Beni Biological Station is that some of the game animals the Chimane hunt and eat are endangered primates such as spider monkeys (Ateles spp.), greatly appreciated in their diet.
The Chimane complement hunting and fishing with shifting agriculture and making handicrafts. Much of their agricultural production is for subsistence, but they also sell their surpluses in local markets. (This is their main source of income.) They cultivate more than 80 food, medicinal, and fiber-producing plants, mainly rice, bananas, cassava, maize, squashes, and a wide range of fruits. Their agricultural activities are based on detailed knowledge of the soil types, based on criteria such as color, structure, texture, and drainage. This knowledge helps them to control pests and obtain the greatest production from cultivated land. They also earn income from paid labor, the sale of craft products made by the women, and the gathering and weaving of jatata (Roystonea regia), a roofing material traditionally produced by the Chimane.
The local mestizo population hunts very little and lives basically on their cattle and crops. Unlike the natives who do very well from their wild food sources, the campesinos consider fish and game as special treats, not staple foodstuffs.
After the biosphere reserve received official recognition from UNESCO in 1986, a multidisciplinary team drew up a preliminary management plan containing directives on resource administration, nature protection, research, and public use. There is an office in La Paz to deal with national and international relations. The park's office in El Porvenir houses an administrator, the scientific staff, and the wardens, and also provides basic facilities for researchers and visitors. Bolivian biologists started a comprehensive biological inventory helped by a small program of grants. The basic physical and vegetation maps were drawn up, and a census was taken of the human population in the reserve and its surroundings. Several institutions contributed additional funding. The data collected in these studies were analyzed and used to zone the reserve. In 1988, the administrative staff of the Beni Biosphere Reserve, together with the Interdisciplinary Center for Community Studies, started projects to solve the problems of the peasant communities in the fields of health and food production. This both improved the living standards of the local people and taught them about the importance of conserving natural resources. The many completed studies, reports, and projects make Beni Reserve a reference point when starting resource exploitation programs in other areas of Bolivia.
Since the reserve was created, environmental education programs seem to have been well received among the local people, though their practical effects are yet to be seen. The current challenge is to integrate local people in the reserve's administration and put the concept of the biosphere reserve into practice. The environmental administration program is vital to maintaining the reserve's ecological integrity. The program focuses on two main points: protection and resource management.
This program is governed by the zoning in the reserve set out in the management plan. Special controls have to be applied 1) in the zones where natural resource usage is restricted and 2) in those zones intended for the regeneration of the wild flora and fauna. The biosphere reserve has a group of park wardens and forest police, all of them from the Beni area. Patrolling the reserve is not only the responsibility of the park's wardens; local communities and institutions are also involved.
The resource management program seeks to combine biological conservation with sustainable development within the biosphere reserve. This program mainly uses traditional knowledge of the ecosystem and resource management, especially in the field of agroecology. One of the most interesting projects is the management of the turtle Podocnemis unifilis in the Maniqui River. The project began with a study of the abundance of the species and a questionnaire-census on human usage of these turtles. The results were used to design a project to allow turtle populations to recover and to create a management plan for the species. Another recovery program affects the black caiman (Melanosuchus niger), which is endangered throughout Amazonia. A group of caimans from a captive breeding program were released in the Normadia Lake, where their adaptation to life in the wild is being observed. The shallow lake near El Cedral houses a natural caiman population that is observed as a control. Several resource use programs are now under way, including ones dealing with grassland usage and management of the peccary (Tayassu pecari) and the collared peccary (Tayassu tajacu). Others programs are being planned, among them a management plan for the black spider monkey (Ateles paniscus), studies of land use and cultivation systems in Beni, research into the native savannah species, and studies of the area's promising medicinal and food plants.
The Beni Biosphere Reserve has also attracted attention for its role in the world's first "debt-for-nature" swap, held in 1987. The principle of debt swaps is as follows: an interested party, including an international conservation donor, buys part of the commercial debt of a debtor country at a discounted price (typically a third of the full figure) from international banks eager to recoup losses. A national bank then agrees to pay off the discounted debt in local currency to a value of say two-thirds of the original sum. Thus, the international bank obtains some payment on its original loan, the debtor country is relieved of a portion of its debt, and the donor organization multiplies its investment (in this case twofold). In the case of Beni, the Conservation International, a U.S. non-governmental organization purchased $650,000 (U.S.) of Bolivian debt for a discounted price of $100,000 (U.S.). The debt was then surrendered in exchange for a commitment from the Bolivian government of 1.5 million hectares of land (1 hectare=2.5 acres) and $250,000 (U.S.) maintenance funds to expand existing protected areas in northwestern Bolivia to form the Beni Biosphere Reserve.
This first "debt-for-nature" swap became highly controversial because the political sectors opposed to the payment of Peru's foreign debt opposed the scheme as well. The Chimane also withstand it because of the logging concessions in their territory, the Chimane Forest Reserve. The Chimane were encouraged to move to a buffer zone that was already being exploited by ranching and logging interests. The Gran Consejo Chimane was created to represent the Chimane people and to promote land titling in the nearby Bosque de Chimanes. This culminated in the Chimane and other local people marching to La Paz to protest. Over 300 indigenous residents of the Beni took part in the March for Dignity and Land. They took a month to march from Beni to La Paz in order to take their case to the federal government. Almost immediately, the Bolivian president granted the indigenous people land rights within the Bosque de Chimanes and required timber companies to leave the area.
2.3 The biosphere reserves in the African savannahs
Twenty-two biosphere reserves in Africa contain significant amounts of savannah of some type, and in practice two-thirds of them correspond to the savannah biome. They include all types of savannahs, but most are grassy savannahs, mainly in the countries of eastern Africa such as Kenya (Mount Kulal and Amboseli), Sudan (Dinder and Radom National Parks), and Tanzania (Lake Manyara and Serengeti-Ngorongoro National Parks).
The Serengeti-Ngorongoro Biosphere Reserve
The Serengeti-Ngorongoro Biosphere Reserve contains some of the most famous conservation areas in Africa and is home to the greatest concentration of large mammals on the planet. It is in northern Tanzania, to the east of Lake Victoria, and consists of the Serengeti National Park, the Maswa Game Reserve, the proposed Grumeti and Ikorongo game reserves, and the Ngorongoro Conservation Area (NCA). Both Serengeti National Park and Ngorongoro Conservation Area are World Heritage Sites.
The Serengeti National Park (endless plains in Masai) was gazetted in 1940 and was the first national park to be created in Tanganyika (now part of Tanzania). It currently covers an area of 1,476,300 ha (1 ha=2.5 acres). When the park's limits were decided in 1948, the Ngorongoro Crater Highlands were included, but in 1959 this area was excluded and reclassified as a conservation and multiple land use area. The 828,800 ha Ngorongoro Conservation Area is administered by the Ngoron-goro Conservation Area Authority (NCAA) and was incorporated into the Serengeti-Ngorongoro Biosphere Reserve in 1982. A conservator appointed by the NCAA is responsible for all the activities within the area. The total protected area, including the two proposed game reserves in Grumeti and Ikorongo, covers an area of 2,695,000 ha.
Natural characteristics and values
Olduvai Gorge is located near the boundary between the Serengeti National Park and the Ngorongoro Conservation Area. It is a deeply incised seasonal streambed draining into Lake Lagarja. The gorge cuts downwards through two million years of deposits, and the site became world famous in 1959 when Mary Leakey (1913-1996) found the skull of the hominid Zinjanthropus (now Australopithecus boisei) while working in the area from 1931-83 with her husband, Louis Leakey (1902-1972). The area became even more famous after the discovery of more hominid remains of Homo habilis and Homo erectus (see pp. 244-247). A total of 33 fossil hominid specimens have been recovered from the nearby site of Laetoli above Lake Lagarja, where fossilized hominid footprints were found preserved in 3.7-3.5 million-year-old volcanic ash (shown in photo on p. 245). These footprints helped establish when hominids started to walk on two feet.
The Olduvai Gorge and other sites in the NCA have also yielded a vast array of fossilized animal bones and stone tools, and together with pollen and sediment analyses, this has made it possible to reconstruct the paleoclimates and paleofloras. These reconstructions suggest there was a dynamic mosaic of savannah grassland and woodland that was perpetually changing due to shifting climate patterns and volcanic activity. Olduvai has established the importance of the Serengeti-Ngorongoro Biosphere Reserve as a unique evolutionary showcase, continuously used by hominids and humans for 3.5 million years or more.
The Serengeti-Ngorongoro Biosphere Reserve is on a plateau ranging from an elevation of more than 9,842 ft (3,000 m) in the southeast of the Ngorongoro crater to 3,018 ft (920 m) near Lake Victoria in the west. The area's geological materials are mainly pre-Cambrian, with areas of very old volcanic rock and ironstone up to 2,500 million years old. Much of the Serengeti consists of gently rolling ridges and valleys, with hills rising 328-984 ft (100-300 m) above the surrounding countryside. The almost flat south and east of the Serengeti Plain were formed by repeated deposits of layers of volcanic ash from the still active Oldoinyo Lengai Volcano. In some areas, the plains have scattered granitic outcrops (kopjes). Farther south, the plains rise to the Ngorongoro Crater Highlands, consisting of several volcanic mountains such as Olosirwa, 12,073 ft (3,680 m), Loolmalasin, 11,768 ft (3,587 m), and Oldeani, 10,394 ft (3,168 m). Ngorongoro is an enormous volcanic crater 10-12 mi (16-19 km) in diameter with a flat bottom 1,3121,969 ft (400-600 m) below the crater's rim.
The Serengeti drains mainly to the west, toward Lake Victoria. There is little permanent water in this part of the reserve. The Mara and Bologonja rivers in the northern Serengeti are the only watercourses that bear water all year-round, the others are seasonal. Towards the east, in the Ngorongoro Highlands, there are at least 20 permanent streams that flow toward lakes in craters or seasonally flooded depressions. There are several lakes in the reserve, including Lake Lagarja, Lake Masek, and Lake Magadi, and those in the craters of Ngorongoro and Empakaai. Most surface waters are alkaline, giving rise to soda lakes.
There is typically a short rainy season in November-December and a longer one in March-April. The dominant winds are from the east and are strongest in the dry season. The highest rainfall (up to 59 in [1,500 mm] per year) is in the area with the steepest relief facing the dominant winds. The lowest rainfall (16-18 in [400-450 mm] per year) is in the rain shadow to the west and northwest of the Ngorongoro Highlands, which acts as a barrier to the rains from the Indian Ocean. To the northwest, rainfall increases along a gradient toward Lake Victoria and the other Great Lakes, where it is considerably higher (up to 47.2 in [1,200 mm] per year). The warm dry winds increase evaporation in the plains and reduce the effects of the rainfall. January and February are normally the hottest months, while July and August are the coolest. There is a hot dry season between July and October, and the driest month is normally July. Temperatures rarely exceed 90[degrees]F (32[degrees]C) or fall below 50[degrees]F (10[degrees]C). The average annual temperature in Seronera in the central Serengeti is 71[degrees]F (21.7[degrees]C) and is relatively constant throughout the year. Olduvai Gorge is one of the hottest parts of the reserve, as temperatures may reach 100[degrees]F (38[degrees]C). In the highest areas of Ngorongoro, average temperatures are lower than in the lowlands, and the relief introduces major microclimatic changes. For example, frosts are common in the higher areas, especially between May and July.
The grassy savannahs of the Serengeti Plains are a continuum of low, medium, and tall grassland communities. The low grass plains consist of dwarf growth forms of grasses like Digitaria macroblephora and Sporobolus marginatus, and sedges (Cyperus spp.) in volcanic soils with high potassium, sodium, and calcium levels. They are intensely grazed in the rainy season. In the west of the reserve, the tall grass savannahs of Themeda triandra and Pennisetum mezianum often burn fiercely, preventing any woody vegetation from establishing in them. There is an intermediate grassy savannah dominated by gnu grass (Andropogon greenwayii) in the west and south of the low grasslands, in areas with deeper soils and higher rainfall.
The south and center of the Serengeti are dominated by woody savannahs with deciduous or semideciduous trees, mainly species of Acacia and Commiphora. Acacia drepanolobium and A. tortilis are the most common species, and Commiphora trothae is also abundant. There are relict patches of semideciduous broad-leaved thickets dominated by Combretum molle (Combretaceae) along the valleys and ridges, and in the north there are dense thickets dominated by species of Croton (Euphorbiaceae), Teclea (Rutaceae), and Euclea (Ebenaceae). The kopjes have their own characteristic vegetation, and there are islands of different vegetation surrounded by grassy savannahs.
The gallery forests are virtually restricted to the rivers Grumeti, Mbalageti, Duma, and Mara, and the areas surrounding watercourses. In the most disturbed areas of the Ngorongoro Conservation Area, on the wetter, east-facing slopes, there are montane forests dominated by Hagenia abyssinica (Rosaceae), heaths, and montane thicket. The drier, higher areas--at an elevation of about 6,562 ft (2,000 m)--are dominated by montane forests of Acacia lahai, while the bottom of Ngorongoro crater is occupied by grasslands with scattered freshwater and salty lakes, wetlands, and two patches of woodland. One woodland is dominated by Acacia xanthophloea (Leguminosae) and Rauwolfia caffra (Apocycnaceae), and the other is dominated by Cassipourea malosana (Rhizophoraceae), Albizia gummifera (Leguminosae), and Acacia lahai (Legumi-nosae). Above 7,218 ft (2,200 m), there are montane tussock grasslands dominated by Eleusine jaegeri, while at lower elevations, below 7,218 ft (2,200 m), Pennisetum sphacelatum tends to dominate.
The number of species in the conservation area does not exceed a thousand but includes some endemic species. The grass Holcolemma transiens occurs mainly within the Ngorongoro Conservation Area (NCA); the herbaceous Ethulia ngorongoroensis (Asteraceae) is only known from around the short grass and bushlands area within the NCA; the climber Neonotonia verdcourtii (Asteraceae) lives in the Ngorongoro crater and the grasslands on its rim.
Very many mammal species live in the Serengeti. The most abundant large mammals are the brindled gnu (Connochaetes taurinus), with about 1.3 million individuals; zebras, with 250,000 individuals; Thomson's gazelle (Gazella thomsonii), with 400,000; and common eland (Taurotragus oryx), with 12,000. The other mammals include the Cape buffalo (Syncerus caffer), topi (Damaliscus lunatus), Coke's hartebeest (Alcela-phus buselaphus cokei), Grant's gazelle (Gazella granti), oribi (Ourebia ourebi), warthog (Hylo-choerus), giraffe (Giraffa camelopardalis), African elephant (Loxodonta africana), hippopotamus (Hip-popotamus amphibius), black rhinoceros (Diceros bicornis), and seven species of primates. Predators are abundant--among them the lion (Panthera leo) and the laughing hyena (Crocuta crocuta)--and 21 species of ungulates have been recorded. Elephants were not originally considered a significant component of the area's fauna, but loss of grazing and harassment outside the reserve have led a population of nearly 450 to take up residence within the reserve.
The Serengeti Park is famous for its spectacular migrations of gnus (Connochaetes) and other large herbivores. It is one of the last places on Earth where such large seasonal movements of ungulate biomass still occur. They are following the seasonally available grazing in the grasslands and the waters of the plains and adjacent forests. Since the deadly rinderpest disease was controlled among local cattle, the number of gnus in the Serengeti has increased to 1.3 million. The main migratory population moves within an area of 250,000 [km.sup.2], two-thirds of it within the Serengeti-Ngorongoro Biosphere Reserve and the neighboring Masai Mara Wildlife Reserve on the other side of the frontier with Kenya. The roughly 10,000 gnus require an area of about 250 km2. Gnus rapidly deplete the pastures, as they graze short grass very efficiently and are present in large numbers, forcing them to move continuously in search of fresh grazing.
In the rainy season (December-May), attracted by the availability of surface water and tender green grazing, they form large herds on the short grasslands of the eastern Serengeti Plain. This is when all the calves are born, within an extraordinarily short calving period. This strategy probably evolved to glut the predators that pursue them on their migration, while ensuring the survival of enough calves. The calves can stand up within seven minutes of birth and stay with their mothers for between 6 and 12 months. Their main predators are laughing hyenas, as well as lions, leopards, and African hunting dogs.
When the dry season starts (around May or June), the gnus leave the plains for the wetter woody savannahs to the north and west around Lake Victoria, and cross the international border into Masai Mara, where rain is more likely to fall out of season. The mating period, or rut, is at the beginning of their migration; within an extraordinarily short period (three weeks), about 90% of the sexually mature females are mated by the bulls. The bulls may reach a density of 280 km2. The migration covers an annual route of about 497 mi (800 km) and crosses areas where the gnus enter contact with the Masai herders. Gnu calves are infectious vectors of malignant nasal catarrh, a disease that is deadly to cattle, so the Masai keep their herds away from the areas where the gnus migrate.
The Ngorongoro Crater is the habitat of many species and is probably the only part of the reserve where a significant number of black rhinoceroses still survive. The forest fauna is poor when compared with other mountain areas, though there are buffalo, rhinoceros, elephant, giant forest hog (Hylochoerus meinertzhageni), and bushbuck (Tragelaphus scriptus). Most of the wild ungulates in the Ngorongoro Conservation Area move into the crater during the dry season, apart from Grant's gazelles, giraffes, elands, and impalas. There is evidence that some gnus, zebras, elephants, and buffalo migrate out of the crater and then back again, though most of the 10,000 to 20,000 gnu within the crater are probably resident. The crater contains a very high concentration of lions and laughing hyenas, a uniquely high concentration of large predators. The cheetah (Acinonyx jubatus), African hunting dog (Lycaon pictus), leopard (Panthera pardus), serval (Felis serval), and caracal (F. caracal) visit the area occasionally.
More than 530 species of bird have been recorded. Many greater flamingoes (Phoenicopterus ruber) and lesser flamingoes (Phoeniconaias minor) feed in the soda lakes and salty lakes such as those in the Ngorongoro Cater and Lake Natron and Lake Magadi.
Management and problems
Evidence shows the Ngorongoro Crater has been occupied by herders for at least 2,000-2,500 years. Until the early nineteenth century, the crater was occupied by Datoga (or Taturu/Dadog) herders, who now live farther south in the arid plains at the base of Mount Hanang. They were ousted by the Masai, who had been moving south from the arid Lake Turkana (Lake Rudolf) depression during the seventeenth and eighteenth centuries and who imposed their culture and language on most of the peoples in the region.
When the Serengeti National Park was created, about 1,000 Masai and 50,000 head of cattle were resident in the protected area. Cultivation and herding were permitted within the park, but farming was banned in 1954, as it was thought to be harmful to wildlife. This controversial decision was reconsidered in 1959, when the entire park was divided into two parts. The western part (with some additions on its northern edge) became the Serengeti National Park, while the eastern part became the Ngorongoro Conservation Area, within which herding and farming were allowed to continue. All the Masai resident in the Serengeti were moved to the Ngorongoro Conservation Area. The government promised the Masai that it would build wells and reservoirs to compensate them for the loss of their lands in the Serengeti.
As some animals--especially buffaloes, gnus, and zebras--migrate outside the Ngorongoro crater during periods of drought, there was some concern that their migration routes might be interrupted by unplanned settlement or agricultural development. Continued cultivation within the Ngorongoro Conservation Area was held to be negative, and in 1975 the Masai were again forbidden to settle and farm within the crater. About 25,000 Masai now live within the Ngorongoro Conservation Area with about 285,000 head of cattle, and 75% of the area is grazed by cattle. The Masai have traditionally shown little interest in hunting wild animals.
In the last few years, discontent has grown among the Masai living in the Ngorongoro Conservation Area, mainly because they are disadvantaged in comparison with other collectives in terms of housing, education, health, and other social services. This discontent has increased in parallel with the rapid population growth (from 8,700 inhabitants in 1966 to 22,600 in 1987). The number of head of cattle has not grown as fast as the number of herders, and the Masai can no longer live from their traditional diet of milk and meat. Cereals are now their staple foodstuff, and unless they receive them as a subsidy, the Masai will have to be allowed to grow them if their herder lifestyle is to remain viable in the Ngorongoro Conservation Area.
In an effort to help the Masai living in the Ngorongoro Conservation Area, the NCAA grants them a percentage of the income derived from park entrance fees and has committed itself to 1) buying veterinary pharmaceutical products for resale at cost price, 2) constructing cattle dips, and 3) supplying water points. Yet recent reports have drawn attention to the great imbalance between the NCAA's large investments in tourism and conservation and its low input into the development of veterinary, sanitary, hydraulic, and community services.
The Serengeti-Ngorongoro area is one of the most thoroughly researched in Africa, partly because of its great habitat diversity but mainly because it is now unique in containing huge herds of migrating ungulates coexisting with a high density of predators in an unspoiled and almost intact system. Researchers have also been attracted by the low level of human population in much of the area, which allows pure research into the savannah wildlife. Much early research was on natural history or only a single species, without great immediate relevance, but several of the earliest publications are now landmarks in wildlife biology. Recent research is tending more toward community and systems ecology, and human beings are beginning to be considered as an integral part of the ecosystem.
Since its establishment in 1962, the Serengeti Wildlife Research Center, a paragovernmental research institute in Seronera, has provided research facilities such as an herbarium and library for resident and visiting scientists. The center's income for maintenance and development comes from renting accommodations to the scientists, from donations, and from government subsidies.
Research needs to be directed toward improving management, as ecological, social, and economic pressure is building up in the area; the 1990-1995 Management Plan for the Serengeti National Park urged the development of a long-term research program. Serengeti has also been chosen as a potential site for inclusion in an international network of sites for biodiversity inventory and monitoring. Fifteen priority research areas have been identified, focusing mainly on 1) the population dynamics of the nearby human groups, 2) the impact of tourism, 3) resource inventories, 4) ethnobotany, 5) the effects of fire, 6) endangered species and habitats, and 7) invertebrates and small mammals.
The Serengeti-Ngorongoro Biosphere Reserve is the most visited of all Tanzania's parks, accounting for 25% of total visitors. They come to see the spectacular migrations of animals over the plains and the attractive landscape and wildlife of the Ngorongoro crater. Two lodges and one campsite have been built at Lobo and Seronera within the Serengeti National Park, and five more within the Ngorongoro Conservation Area. International tourism is increasing, and local tourism is also growing, especially in the Ngorongoro Conservation Area, as a result of educational visits from schools and other institutions. In the Serengeti, most local visitors are in transit between Arusha and Musoma or Mwanza.
Most of the tracks to see big game in the wild are in the Seronera Valley and Ngorongoro Crater, and park guides are available to accompany excursions to view the wildlife. Most visitors use guides and chauffeurs from tourist companies. In the Ngorongoro Conservation Area, the NCAA retains 40% of the income derived from foreign tourism and 100% of those generated by local tourism. About 92% of the NCAA's income comes from the tourism it receives. Four more tourist lodges are planned in the Serengeti National Park, and another two in the Ngorongoro Conservation Area, all financed by private investment. There is no plan to limit the growth of tourism, and the siting of the developments was chosen totally against the criteria of the NCAA and its board of directors. There has also been criticism that the park does not exploit its full potential as a source of foreign exchange, with the danger that the area may be used for aims other than conservation.
It is not at all surprising that a system as large and productive as the Serengeti-Ngorongoro Bio-sphere Reserve is subject to many of the standard problems now facing the managers of Africa's protected areas. The reserve's main management problems are probably due to local human pressures. The Serengeti National Park lies between increasingly dense farmer populations to the west and stockraisers to the east. A further complication is that cattle rustling is conducted across the park, with all the problems this implies. Another related problem is that no income or other direct benefits from tourism or the sustainable use of resources reaches local people or district councils--the very people who lost their ancestral rights due to the park's previous management policies. This has led to a breakdown in communication between park staff and local and district authorities. The growing disenchantment of the Masai residents with the Ngorongoro Conservation Area is a serious problem, made worse by the fact that management is split between the NCA and the Ngorongoro District Council, which means responsibilities are unclear.
As already mentioned, the government has no regional policies or general guidelines on the development or use of tourist facilities or on environmental protection. Management practice in the area has developed under the guidance of foreign scientists, and, perhaps, in the long term, more pragmatic policies based on local values, needs, and ecological history might be more viable.
Poaching is common, especially in the north and west of the Serengeti Park. Snares are normally used, and often vehicles are used to transport the illegally hunted meat to market. Migratory species are less affected than resident ones; the Mara River hippopotamus (Hippopotamus amphibius) and the Cape buffaloes (Syncerus caffer) in the northwest of the park have been worst affected. Poaching for ivory and rhino horn was so intense that from 1977-1986 the population of black rhinoceros (Diceros bicornis) in the Serengeti Park fell from several hundred to one or two survivors. There is now concern for the future of the African hunting dog (Lycaon pictus) in the reserve, as it is too small for the gnu's entire migration route.
2.4 The biosphere reserves in the southeast Asian savannahs
Only three biosphere reserves in southern Asia contain large areas of savannah; these areas are mixed with monsoon forests, which are locally considered more valuable. Two of these biosphere reserves are in Thailand--the Sakaerat Research station and the Mae-Sa-Kog Ma Environmental Research Sta-tion--and the third is on the Indonesian island of Komodo. In the two biosphere reserves in Thailand, open forests of dipterocarps comparable to woody savannahs (see p. 85) occupy relatively small areas in a context dominated by monsoon forests. The Komodo Biosphere Reserve, described below in more detail, contains both woody and grassy savannahs, which between them cover three-quarters of the reserve, while the rest is covered by monsoon forest (see also volume 2, p. 496).
The Komodo National Park Biosphere Reserve
The Komodo National Park is in the province of Nusa Tenggara Timur in the Sape Strait separating the islands of Sumbawa and Flores; it consists of three of the smallest islands in the Strait, namely Komodo, Rinca, and Padar. In 1980 and 1984, the national park was extended to include the surrounding area of sea and now covers an area of 219,000 ha (1 ha=2.5 acres), only a quarter of them dry land. The biosphere reserve is a part of the national park and has the same name, but it only includes an area of 30,000 ha on the island of Komodo. Its nomination as a biosphere reserve and the increase in the size of the national park were a political maneuver forming part of a development plan seeking balanced regional development and growth.
Komodo Island is the largest unit within the national park. It is 22 mi (35 km) long from north to south, and 3-9 mi (4-15 km) from east to west. It is very typical of the conditions in the Lesser Sunda Islands, as it lacks the abundant terrestrial species found on the islands farther to the north due to the absence of large areas of rainforest. Most of Komodo Island is covered by woody and grassy savannahs, with remnants of deciduous monsoon forests at the base of hills and in valley bottoms. The very rugged coastline has mangrove forests in the most protected bays.
The island is best known as the home of almost all the populations of the Komodo dragon (Varanus komodoensis), the world's largest monitor lizard (Varanus), whose total population is below 6,000. The woody savannah suits the lizard and contains large populations of wild primates and ungulates as well as domesticates (mainly horses and buffaloes). The lack of fresh water means the human population is low (a little over 600), giving the reserve's managers a unique chance to conserve this unique species while obtaining the population's collaboration by encouraging the development of traditional marine activities and tourism.
Natural features and values
Komodo Island's steep relief reflects its position on the active shatter belt separating the Australian and the Sunda tectonic plates. The island was shaped during the Pleistocene, a period of great volcanic and tectonic activity, though studies of its flora and fauna suggest that the chain of islands it forms part of has emerged and been submerged more than once since the Miocene.
The reserve has a generally mountainous landscape, dominated by a ridge running north-south at elevations of 1,640-1,968 ft (500-600 m). These highly eroded mountains are rounded in appearance. Only a few isolated peaks in the northeast of the island are less eroded; one of them is the peak of Gunung Todo Klea, whose walls are vertical and topped by a series of pinnacles and steep rock gullies that often reach down the mountainside, the dry beds of seasonal watercourses. The island's coastline is rocky and irregular, with small bays, coves, and white sand beaches separated at times by cliffs rising vertically from the sea. Navigation around the island is very difficult due to the combination of the bays, the coral reefs, and the strong tidal currents, and this helps explain why the island has remained relatively uninhabited by human beings. The geological significance of Komodo Island and its current physical characteristics make it a useful area for the study of natural history and evolutionary processes, and they should feature strongly in any management plan that seeks to make the island something more than just the home of the Komodo dragon.
Little meteorological data is available for Komodo, but it is possible to estimate on the basis of the data from the observation stations on the nearby larger islands. The most important factors governing the climate are the northwest monsoon and the trade winds from the southeast. They have completely different influences on the topographic and vegetation characteristics of the reserve, which vary greatly from those of the other Indonesian islands. The monsoon season lasts from January to March and is characterized by alternating periods of calm weather and very stormy weather, with higher humidity and lower temperatures than in the dry season. Most of the island's rainfall--32-39 in (800-1,000 mm) per year--falls during the monsoon months. In the dry season, humidity is lower and ground temperatures may exceed 112[degrees]F (44[degrees]C). The trade winds from the southeast make conditions at sea very dangerous (as is fishing, the livelihood of most local people). These extreme climatic conditions may also have adverse effects on land, causing severe erosion by water or by wind. Such adverse circumstances, when combined with the human influence within the reserve, may explain why the slopes on Komodo are so barren and hostile in comparison to other islands in the region.
Woody savannahs and tall grass savannahs dominate Komodo Island's vegetation, covering 70% of the island. Unlike the islands of Indonesia farther to the east, Komodo's savannah landscape is not dominated by Australian tree species. The monsoon forest is thus more open and spiny. The most common species is the lontar palm (Borassus flabellifer), scattered in patches throughout the reserve. The slopes show a distinctive transition of types of grassland reflecting differences in the frequency of human-induced burning to obtain grazing for their cattle.
Most of the island's grasses were introduced by human beings. The most important ones are Eulalia leschenaultiana, Setaria adhaerens, and in the higher areas Themeda frondosa and T. triandra. These grasses are important in maintaining the populations of wild animals in the reserve. Though the frequency of burning has recently been limited, the savannah vegetation will probably persist due to the associated soil changes. Notable woody species on the lower slopes of the mountains include Murraya paniculata (Rutaceae), Diospyros javanica (Ebe-naceae), and Harrisonia brownli (Simaroubaceae). They are also present in the dry monsoon forests that occupy almost a quarter of the island. These forests are very important to the reserve's management, as they are the Komodo dragon's preferred habitat. The lizard's prey mainly live in the higher areas, but in the dry season the animals have to descend to the lowlands in search of water.
Some of the highest mountains on the island contain isolated patches of evergreen cloud forest. There, far from the habitual burning, the forest contains species typical of wetter environments. Of great scientific importance, they provide an opportunity to study climatic changes in the region and the extent of human modification of the natural environment. The cloud forest may also be of use in observing the evolutionary pattern of the Komodo dragon, as it is the preferred habitat of many of its prey. Though they only cover a small percentage of the island, these forests show high floristic diversity. There are many areas of rattan, bamboo groves, and trees like Terminalia zollingeria (Combretaceae), Podocarpus neriifolius (Podocarpaceae), Uvaria rifa (Annonaceae), Ficus orupacea (Moraceae), Mischocarpus sundaicus (Sapindaceae), and Glycosmis pentaphylla (Ruta-ceae). The only other forests are those of the common mangrove (Rhizophora mangle) and the Pacific red mangrove (R. stylosa), found in some small sheltered bays or coves.
The Komodo dragon was presented to the scientific community in 1912 by Dutch zoologist P.A. Ouwens, then director of the Bogor Zoological Museum. He had followed up bloodcurdling reports from Malay pearl divers of "huge lizards that stalk the beaches." Since then the lizard has been the center of scientific controversy. It offers researchers a model for the study of evolutionary changes in isolated animal species and provides convincing evidence of the factors governing natural selection.
Except for a few locations on the island of Flores, the Komodo National Park contains the world's entire population of Komodo dragons. The largest and heaviest of all lizards, it can exceed a length of 10 ft (3 m) and a weight of 198 lb (90 kg). It has a fierce reputation, but local legends greatly exaggerate things to boost interest in the animal and thus benefit the islanders. The Komodo dragon owes its extraordinary longevity to its great adaptability. The environments on Komodo Island, like all islands, are especially vulnerable to external influences, and the reptile's environment has changed noticeably since its discovery. Within the biosphere reserve, human beings are the only direct threat to the reptile's survival, though it depends on the few edible species on the island and is thus very sensitive to any reduction in their numbers. One of the reserve's main management problems is poachers hunting the sambar deer (Cervus timorensis) with dogs. Once the poachers are finished, the dogs are abandoned on the island and then compete with the lizards, forcing them to adapt their feeding habits to become carrion-feeders rather than predators. The lizards can detect wounded animals from a distance and can even be seen on the beaches searching through the remains left by the fishing boats.
The Komodo dragon's natural environment is the lowland forest, where it hides in wait for its prey by the natural paths they follow. When prey passes by, the lizard generally grasps at its legs, and those that temporarily escape are soon tracked down. Like most animals who are masters of their domain, the Komodo dragon feeds a considerable time after finding its food. As there are no competitor predators, the young lizards fend for themselves almost as soon as they hatch; the female adults lay 20 eggs in each clutch. The younger lizards' only competitors are the older lizards, and as they are lighter, they can search the trees for food, finding birds, bird eggs, insects, rats, and even bats.
Human influence on the populations of Komodo dragons in the reserve have had very different, almost contradictory, results. Deliberate fires increase erosion and reduce the available habitat, but they help the lizards in the short term. The savannah areas created by the fires are the favorite habitat of the Strait sambar (rusa deer), one of the lizard's favorite preys, and it can hunt more effectively in the shorter grasslands created by repeated burning. Tourism also raises some problems, though tourist income helps management activities. Overfamiliarity with tourists, the result of sites where bait, such as a tethered goat, is left to attract the dragons so they can be seen more closely, has led to a revision of management practices. New proposals for a more balanced program based on nature routes cannot be expected to function without dealing with the even worse problems of the wild dogs and the poaching of deer. The problems' roots lie in the inadequate legislation and in the existence of a market for the products of poaching rather than in the reserve's management.
The designation of this area as a biosphere reserve was based excessively on the presence of the Komodo dragon. Other Indonesian islands have comparably diverse flora and fauna, but none shows such a wide variety of evolutionary influences as Komodo Island. Geographical isolation, the lack of competition between predator species, an especially harsh environment, rises and falls in sea levels, climate change, and volcanic activity have all contributed to the island's current morphology and ecological status. These factors place Komodo Island in the same category as the Gal Pagos Islands and the Hawaiian Islands in terms of its scientific interest, and like them, it deserves individual study. Though the Komodo dragon is unique, the island has a complex flora and fauna that is representative of one of the most important biogeographical divisions in the world, Wallace's Line. (See volume 2, map 102, p. 160.) Wallace's Line, named after A.R. Wallace, the scientist who first defined it, marks the transition between the Oriental and the Australian biogeographical regions. There has already been much research into problems such as species migration and colonization in periods of biogeographical change. Other species on Komodo may play an important role in this, as the island has a total of seven endemic species of terrestrial mammal, including the Komodo rat (Komodomys rintjanus) and the crab-eating macaque (Macaca fascicularis). Seventy-two species of bird have been recorded, including the yellow-crested cockatoo (Cacatua sulphurea) and the noisy friarbird (Philemon buceroides).
There have already been some geological studies of the island, and interest in the Komodo dragon has helped research into several questions such as island giantism. Perhaps its most important contribution to research has been in relation to evolutionary theory. Continued research with increasingly sophisticated field observation and advanced laboratory techniques (such as genetic mapping) will reveal more information about the island and the Komodo dragon and could also provide further insight into the enormous diversity of the surrounding marine ecosystems.
The marine environment around Komodo fulfills all the conditions needed for inclusion in the biosphere reserve. It is of interest to marine scientists, an adequate environment to support the local population, and an efficient buffer for management proposals for the reserve's conservation. The marine environment around Komodo is one of the most biologically productive areas in the world. The very rich ecosystem of coral reefs results from the upwelling of nutrient-rich deep seawater.
Fishing activities around the island have recently been regulated to avoid overfishing, and the national parks authority responsible for the reserve has proposed an extension of the intensive use zone to cover a radius of 3,281 ft (1,000 m) around the island. Almost all the inhabitants fish for squid and reef fish at night with nets from twin-hulled small platforms locally known as bagan. The continuation, or expansion, of traditional fishing is a key part of the proposals for the reserve's management. It is hoped that this will allow the fishers to broaden their fishing practice, thus reducing localized damage to some parts of the reef and, in the long term, reduce the need to exploit the island's terrestrial habitats.
Little is known of the prehistoric human occupation of the region, but it is thought to have been settled for a long time because of its strategic importance and the presence of safe anchorages. The island is believed to have been exploited for the abundant hunting when the forests covered a much larger area than now and there was much more freshwater. Until recently, discoveries were limited to a few poorly understood graves and artifacts. Early human settlement is clearly shown by the finds of Neolithic graves and Megalithic upright statues, like the menhirs of the European Megalithic cultures. They are not very frequent and do not suggest large-scale colonization, probably because the soil conditions were too poor for agriculture. The soils are very infertile and irrigation is almost impossible because of the extreme climate.
The age of the current settlements suggests that the ancestors of the present inhabitants arrived about 150 years ago. The island's oral tradition states that Kampung Komodo, the only village on the island, was founded by a group of outcasts banished from Sumbawa by the sultan of Bima. The current population lives almost exclusively from fishing, but this has not always been the case. The first settlers lived in the mountains, for example in the old village known to have existed on Mount Ora, where small patches of exotic palms and grasslands clearly show very small-scale dry farming was practiced. It has been suggested that the seasonal irregularity of the climate or the increasing scarcity of water, related to the repeated annual fires, forced the colonists to abandon this site and settle on the more productive coastline. Most of the current population of a little more than 500 inhabitants live in Kampung Komodo. This very low population is a key factor favoring the biosphere reserve. The coastal area provides the local people's only means of subsistence, making it unlikely they will invade other areas of the island.
The Komodo dragon has been protected since 1912, when the sultan of Bima decreed a ban on hunting or disturbing it. Local oral tradition retains traces of a collective protection even before this, as the islanders relate their well-being to that of the ora, as the lizard is locally known. This is, however, largely invalidated, as the social structure of Komodo can best be described as autocratic, and the local population fears reprisals for poaching. After the lizard's presentation to the astounded scientific community, more conservation initiatives were proposed, but most came to nothing. American zoologist W.B. Burden visited the island in 1926 and promoted the passage of a law banning the "capturing, killing and possession of live or dead ora." This law was the first significant conservation initiative but was of little use in preventing the destruction of the Komodo dragon's preferred habitat.
In 1938, Padar and Rinca were declared nature reserves. Komodo was declared a nature reserve in 1965, when scientists thought the Komodo dragon was on the brink of extinction. After studies in the 1970s on modifications to the reptile's habitat and a complete inventory of their fauna, the three islands were declared biosphere reserves.
Until the formulation of a management plan in 1980, inadequate facilities and remoteness discouraged tourist visits. Plans for tourism infrastructure adhere to traditional styles suitable for the local environment. Visitors stay in huts on pillars known as pondoks in the reserve's intensive use zone in Loho Liang. The tourists are located there so they disturb the islanders' subsistence economy as little as possible; officials also hope to arouse their interest in features other than the Komodo dragon. Nature routes have been established within the park's wilderness zone and services have been introduced on the coast (for example, boats to go scuba diving on the coral reefs). Some of the local population benefit from this, working as guides or wardens or building facilities for the reserve. At first the employees were not keen on living in the relatively isolated reserve, but they are now much happier with their involvement in the project. They are beginning to see results in the form of improvements in their living standards, as the reserve has financed health facilities and supplies of safe drinking water.
Seeing the Komodo dragon is the greatest attraction for tourists, but it is also the main headache for the reserve's authorities. There are often as many as 20 lizards at the baiting stations, and the management fears that they will end up like the bears in Yellowstone Park. It has been realized that it is necessary to promote nature routes to show the animal in its natural setting. The overall management objectives have been fulfilled, and Komodo Island compares well with other protected areas that are tourist objectives.
Tourism has also benefitted the Komodo dragon, as the management has insisted that income be reinvested in the construction of new facilities for the reserve and the maintenance of the existing ones. Patrol boats, radio links, and close collaboration with the police have led to the detention of many poachers. As a result, the ora population has stabilized in the last few years and may even be increasing.
The disparity between the size of the island and the ability of the wardens to patrol it has meant that poaching, clandestine logging, and abusive fishing practices have become almost constant features of the reserve. The management team used to concentrate its efforts on catching poachers, but this was not cost-effective and dissipated resources that could be put to better use. Not only is it hard to enforce the regulations needed to halt these activities, it is hard to get the appropriate legislation passed. Most intruders come from neighboring islands such as Sumbawa, which belongs to the neighboring province of Nusa Tenggara Barat, and the products of their illegal activities are purchased in markets outside Komodo. Those in charge of the national park cannot obtain appropriate legislation in other provinces. Programs to explain the importance and advantages of nature conservation, and even the project to establish a buffer zone where these activities would be allowed, have not obtained satisfactory results.
This is the reason underlying the national park management's support of an intensive-use zone aimed at exploiting the marine environment and fisheries. In theory, the administration's plan hoped to involve the local population by creating employment. The areas of less importance as habitat for the Komodo dragon could be used to cultivate fruit trees, timber, and bamboos for export, thus providing income for local families. This is done by the authorities issuing legal permits. It has been impossible to regulate fishing by permits, and the still-common use of explosives damages the reefs. The local community is concerned that fishers from other islands are causing the damage, and some locals now take advantage of the growing number of tourists to offer boat trips and other services.
2.5 The biosphere reserves in the Australian savannahs
Australia is the country with the most biosphere reserves representing the savannah biome. Its three reserves, as many as southern Asia or South America, are scattered throughout the Australian mainland. Perhaps some other reserves in the subdeserts in central Australia could also be included as very arid savannahs.
The Prince Regent River Biosphere Reserve
Located at the northern tip of Western Australia in the subhumid Kimberley region, this area has been protected as a total nature reserve since 1964. National park legislation passed in 1976 restricted entrance to the park to those with permits from the park's management.
The Prince Regent River region of Australia is probably one of the world's last genuine wildernesses. The relief includes plateaus crossed by deeply carved river valleys, steep cliffs on the coastline, and winding river valleys. It is mainly representative of the Australian woody savannahs, but the wide variety of ecosystems ranges from mangroves and wetlands at sea level, through dense scrub and gallery forest along the rivers, to scattered grasslands in the highest areas. The varied plant communities of the basin of the Prince Regent River are home to a rich fauna including many well-known native mammals. The complex relief and the dense plant cover make travel through the reserve almost impossible. The only sign of human influence are some traces of Aboriginal settlements, a characteristic feature of this region of Australia.
Natural characteristics and values
The reserve's irregular relief rises from sea level in the northeast of the reserve to 1,640 ft (500 m) in the south. This region, known as the Prince Regent Plateau, is crossed by the Prince Regent River and its many tributaries. The gradual erosion of the sandstones, with the resulting network of steep-sided gorges, rocky outcrops, and spectacular waterfalls, makes it an excellent study area for geologists and a site of extraordinary natural beauty. From the plateau, the Prince Regent River flows northwest into the sea at Saint George's Basin, a natural deepwater harbor surrounded by steep cliffs and broad intertidal mud flats and joined to the sea by a narrow strait.
The west of the bay, and the island near the adjacent coastline and the Changny and Heywood groups, consist of Carpentarian sandstones from the Warton formation, which in some places are 2,953 ft (900 m) thick. From the bay towards the interior there are small intensely eroded plains of Carpentarian sandstones of the King Leopold formation. Erosion by water in the rainy season has completely stripped the Tertiary surface, leaving Quaternary alluvial, sandy, dark soils that are up to 33 ft (10 m) thick.
In contrast to the Prince Regent Plateau, the northeast of the reserve around the Roe River is a combination of basaltic volcanic rocks and sandstones. The smooth landscape's low rounded hills are higher on the reserve's eastern border. These hills are the southwestern prolongation of the Mitchell Plateau and are topped by the remains of an ancient lateritic landscape dating from the the Tertiary. The Mitchell Plateau is one of the most biologically important areas in the reserve because the low soil-covered hills are more easily colonized by the vegetation and the terrain is not so inaccessible to animals as that in Prince Regent.
The Kimberley region has a subhumid climate with a very clear dry season and wet season, which has largely shaped the reserve's hydrology, flora, fauna, and geological formations. Most of the 39-79 in (1,000-2,000 mm) annual rainfall is in the rainy season between November and April; January and February are the hottest and wettest months. The wet season is characterized by violent storms and average temperatures of around 86[degrees]F (30[degrees]C). The seasonal rainfall gives rise to spectacularly different surface runoff patterns over the course of the Prince Regent River. During the wet season, the increase in the river's sediment load is perhaps more noticeable in the lower stretches, near the coast, where the very large freshets and ensuing sediment deposition are very clear. In the higher areas of the reserve, on the plateau, the greater rainfall may be reflected in very sharp increases in volume of flow, which have over the years formed a genuine maze of valleys and gorges.
This interlocking network of rivers and rocks has long attracted the interest of the Aboriginal tribes as a place to camp and to find shade and shelter. Until recently, the Wunambal Aboriginal tribe lived in the lands to the north of the Prince Regent River, the Worora tribe lived in the coastal areas, and the Ngarinyin lived farthest inland. Many areas of the reserve contain Aboriginal art of great scientific and historic interest. Various paintings represent the spirits worshiped and feared by the former tribes (the Wandjina spirit figures, for example). As well as revealing the migratory character and customs of the Aboriginal cultures, the paintings are also an important indicator of the history of human beings in Australia. The full scientific potential of rock art is now being revealed; for example, climate change can be studied by the analysis of pigments and carbon-14 dating techniques.
The reserve has a very rich flora of more than 500 species of vascular plants and a great variety of plant communities: mangroves, monsoon forests, woody Eucalyptus savannahs, grassy savannahs, and riverside scrub. Along the lowland coastal region where the water supply is relatively permanent (Saint Georges Basin, Rothsay Water, Prince Frederick Harbour), there are large mangrove swamps with the Pacific red mangrove (Rhizophora stylosa, Rhizophoraceae), dwarf mangrove (Aegiceras corniculatum, Myrsinaceae), Campostemon schultzii (Bombacaceae), and Sonneratia alba (Sonneratiaceae).
Farther inland, with increasing elevation, the vegetation changes to a woody savannah and denser gallery forests growing along the watercourses, with woollybutt (Eucalyptus miniata), Darwin stringybark (E. tetrodonta), long-fruited bloodwood (E. polycarpa), and round-leaved bloodwood (E latifolia) reaching heights of 49-52 ft (15-16 m). The dominant vegetation on the sandstone plateau is a woody savannah of low clumps with scattered specimens of different species of Eucalyptus and a diverse herbaceous layer with grasses of the genera Heteropogon, Sorghum, and Chrysopogon.
The subhumid climate also permits the growth of isolated patches of the monsoon forest typical of northern Australian, but this only occurs in certain spots of the Prince Regent River Reserve, namely by permanent watercourses and alongside rivers in Enid Falls, Mount Trafalgar, and Python Cliffs. Depending on the soil, these patches may contain delicate shrubs, climbing plants, and trees 66 ft (20 m) tall, with climbers and shrubs located mainly on the most difficult rocky outcrops. One notable species is the orchid Dendrobium dicuphum. The dominant trees are Alstonia actinophylla (Apocynaceae), Albizia lebbeck (Leguminosae), and Myristica insipida (Myristicaceae).
One of the most interesting trees on the reserve is the Australian baobab (Adansonia gregorii, Bombacaceae; see pp. 74-79), which clings to the walls of the gorges along the river valleys. The seeds of these trees are too heavy to be blown by the wind; they reach the valley walls when the river rises or when deposited in the dung of the rock wallabies (Petrogale) that eat its fruits.
The reserve's great biological importance is further shown by the fact that of the 65 species of native mammal in the Kimberley region (a quarter of all Australia's known mammals), 38 live in the reserve, though a complete inventory of the fauna has not been performed. This subhumid zone of the north of the Kimberley region has many animal species in common with Arnhem Land in Northern Territory. Most of these mammals, mainly members of the family Macropodidae (the kangaroos and wallabies), Peramalidae (the bandicoots), and rodents, are found in the rockier upper part of the plateau, except the bats. The very varied bat fauna includes Schreiber's long-fingered bat (Miniopterus schreibersi), Gould's bat (Chalinolobus gouldii), and the black flying fox (Pteropus alecto). The reserve also has some aquatic, terrestrial, and arboreal species of rodent and reptiles, including the threatened Australian crocodile (Crocodylus johnstoni), with a total population of less than 40,000 in the entire continent.
There are also clear similarities between the bird fauna of Kimberley and that of the Northern Territory. The two regions are separated by the relatively dry region around the base of the Joseph Bonaparte Gulf, and many birds can withstand the region's conditions, especially during the dry season. Two of these species are the Torres Strait imperial pigeon (Ducula spilorrhoa) and the Indian green pigeon (Chalcophaps indica). Other noteworthy members of the pigeon family include Ptilinopus regina ewingii and Chalcophaps indica longirostris, while Old World orioles are represented by Oriolus flavocinctus flavocinctus and Specotheres flaviventris.
Most species of mammals, birds, and reptiles are found in the woody savannahs, especially during the dry season, though many have very precise habitats. All the different ecosystems, whether mangroves, woody savannahs, coasts, riversides, or plateaus are home to almost disturbed populations due the reserve's remoteness and the absence of industrial disturbances.
Management and problems
Many of the problems that have arisen in the management of biosphere reserves, such as clearing ground for agriculture and conflicts between humans and fauna, do not occur in the Australian reserves. This is partly because this immense country has very few inhabitants. A reserve such as the Prince Regent Reserve is an exceptional example that fulfills its conservation and scientific research functions and does not include any exploited areas. The reserve requires very little management because of its isolation and does not attract human interest except for research and a few curious tourists.
Like other reserves and parks in northern Australia, the Aboriginal population is being incorporated into management networks. It is hoped that this will protect many of the ancient monuments and rock art more effectively and that the park management will be better able to understand the countryside and its fauna. At the moment, anyone wishing to enter the Prince Regent River Reserve has to obtain permission from the Aboriginal Council responsible for it.
225 The Beni Biological Station Reserve in northeastern Bolivia is one of the protected spaces in the savannah area. Beni contains several different types of woody formation and large areas of floodable savannahs. Thousands and thousands of hectares (1 ha=2.5 acres) are flooded by the rains that fall in the Southern Hemisphere summer, blurring the courses of the rivers, distinguishable only by the gallery forests rising out of the water. Small differences in elevation, just a few tens of centimeters, decisively separate two environments as different as dry land and flooded land (see photo 231).
[Photo: ERF / Ramon Folch]
226 Cape buffaloes (Syn-cerus caffer) form large herds (of 50-500 head) in the Tsavo National Park (Kenya) and also occur in the sub-Saharan savannahs. This artiodactyl can live in a wide range of habitats, though it prefers grasslands where it can find standing water, because it loves wallowing in the mud. The herds are on the move for 18 hours a day at an average speed of 3.4 mph (5.5 km/h). They graze on the move and occasionally stop to chew their cud, especially during the midday heat. The buffalo is known as one of the African savannah's most dangerous large herbivores. The old bulls have a bad reputation for chasing humans and engaging in unprovoked attacks, but this is unjustified; only wounded animals are violent.
[Photo: M. & C. Denis-Huot / Bios / Still Pictures]
227 Groups of carandai palm (Copernicia) are one of the most typical and consistent components of the thickets of the plains savannah, though other genera of palms (Acrocomia, Coccothri-nax, Colpothrinax, Mauritia, etc.) also grow in small groups. In the esteros and hyperseasonal savannahs, these palms have diversified spectacularly. The genus Copernicia, for example, is represented by several species whose range includes both the South American tropical savannahs and the subtropical dry forests and grasslands. Yet the genus shows the greatest diversity on the island of Cuba, where there are a dozen different species.
[Photo: Juan Carlos Munoz]
228 The Indian one-horned rhinoceros (Rhinoceros uni-cornis), with its characteristic skin folds clearly visible in the photo, lives in tall grasslands on the alluvial plains where the herbaceous cover may reach a height of 26 ft (8 m), but it can also be found in the neighboring forests and wetlands, and even in cultivated areas, because its habitat has been so reduced by human beings that it has no choice but to enter croplands. Its diet consists mainly of grass, but it also includes fruit, leaves, the twigs of trees and shrubs, and cultivated plants. The spread of human settlements and poaching for their valuable horns have caused the drastic decline of Indian one-horned rhinoc-eroses, and it is now classified as endangered by international bodies.
[Photo: Jaume Altadill]
229 The golden langur monkey (Trachypithecus geei) is a primate endemic to the frontier region between Assam and Bhutan, west of the River Manas. This species is in danger of extinction, but fortunately the entire population is protected within the Manas sanctuary. This small monkey weighs about 22 lb (10 kg) and is about 24 in (60 cm) long--not counting the tail, which is twice as long as its head. It is mainly arboreal, only descending to the ground in search of water in the dry season. It forms small groups that mark their own territory, though they do not appear to defend them violently. Golden langurs mainly eat plants, with the occasional insect, and also appear to eat salty earth or sand. Two of the golden langur's unusual features are its completely black face and black erectile hairs that grow on its forehead. The rest of its coat is yellow-orange and darker on the belly.
[Photo: Jean-Paul Ferrero / Auscape International]
230 The Waramanga are a group of Australian Aborig-ines who live in the semiarid areas of the Northern Territory, which have always been sparsely populated. They have even adapted their hunter-gatherer economy to these harsh areas. But humans do not always ap-proach the carrying capacity of an area, and thus in semiarid areas and on desert edges (where the Aborigines continually had to be on the move, traveling long distances and carrying provisions for only a few days), human populations were not very abundant. Therefore, under normal conditions, there was a relative abundance of food. Observing this minimum of well-being may lead one to believe that hunter-gatherers lived in harmony with their environment, though, depending on how you look at it, they are limited by the whims of nature.
[Photo: Andre Singer / The Hutchison Library]
231 The wet savannah dominates the dry savannah in the Beni Biological Station Biosphere Reserve (see also photo 225). In fact, the entire Mojos area of Bolivia is very similar to the flooded llanos of Colombia and Venezuela. During the rainy season, from November to March, the flat and badly-drained areas flood, forming shallow temporary lakes that last until the next dry season. The photo shows this type of landscape near the El Por-venir Station, the reserve's logistic center.
[Photo: ERF / Ramon Folch]
232 The biosphere reserves in the world's savannah areas (1998), showing the area in hectares (1 ha = 2.5 acres) and the year they were declared a biosphere reserve. Most of them are in Africa (22 out of 32), and so are the largest ones. The largest of all is the Serengeti-Ngorongoro in Tanzania, which covers 2,305,100 ha.
[Drawing: IDEM, based on data from MAB Program / UNESCO]
233 The red-legged or crested seriema (Cariama cristata) is a member of the crane order (Gruiformes) that lives in the South American cerrado. It is a terrestrial bird that rarely flies, despite having well-developed wings. It prefers to flee predators on foot. When it stops, it always stands in the typical upright position shown in the photo, taken in Beni Reserve (Bo-livia). Like the secretary bird (Spilornis cheela), a member of the falcon order (Falconi-formes), the seriema has a long neck and feet and is well adapted to the tall-grass environment where it lives. Both species occupy the same ecological niche, but on different continents, as they are both predators specialized in feeding on snakes. The seriemas live in small groups and often go near herds of cattle to feed on the small vertebrates the cattle disturb. They normally search for food in groups or in pairs, and this system means they can keep an effective lookout, another adaptation of this bird from the tall grasslands of the cerrado.
[Photo: Adolf de Sostoa & Xavier Ferrer]
234 The settlers of the savannahs and woodlands of the Beni Biosphere Reserve in Bolivia raise stock as a complementary activity, but this is practiced only by the mestizo groups. The native Chimane continue living by their traditional activities: hunting, fishing, and gathering, varying in importance in the different areas where each collective lives, either in the woodland areas or more open savannahs. The native Chimane populations are usually small, and they also practice some shifting agriculture, as is usual in peoples living in highly variable habitats. (The Beni savannah is flooded during the rains and then suffers long periods of drought.)
[Photo: Adolf de Sostoa & Xavier Ferrer]
235 There is much re-search into the fauna in the Beni Biosphere Reserve, including the study of the local armadillos, the most notable being the giant armadillo (Priodontes maximus). The photo shows the preparation at the Estacion del Porvenir of the skins of a different armadillo that lives on the reserve, the nine-banded armadillo (Dasypus novemcinctus).
[Photo: ERF / Ramon Folch]
236 The steep walls and meadows of the Ngoron-goro Crater in the heart of Tanzania enclose one of the most spectacular wildlife reserves in Africa. The wildlife is rich because the crater receives an almost constant supply of water for most of the year, so herbivores do not need to migrate to find fresh grazing elsewhere. In the dry season, when the typical savannah of eastern Africa is virtually a desert, the animal populations in Ngorongoro remain at more than 80% of normal. Two rivers, the Munge and the Lonyokie, supply water to the crater. Along their courses they flow through several swamps before flowing into the blue waters of the lake occupying the lowest part of the crater. This lake has no outlet, and as it only loses water by evaporation, it is becoming increasingly salty, so the aquatic life is restricted.
[Photo: J. L. Klein & M. L. Hu-bert / Bios / Still Pictures]
237 Kopjes, granitic outcrops typical of the Seren-geti Plains, are the result of recent tectonic phenomena, the same ones that formed the Great Rift Valley and the associated volcanic activity that led to the formation of high mountains like Mounts Kilimanjaro, Kenya, and Meru. In the eastern African highlands, the interaction of geological and geomorphological factors has given rise to a great variety of landscapes and plant formations. Some of the savannah types have complicated distributions in-fluenced by soil factors. The remains of the plateau, the horst blocks, and valleys are all affected to a different extent by the current erosion cycle and are covered by different types of savannah, while the scarped slopes and volcanic mountains covered by fertile soils favor the growth of forests. Unlike other points in Africa, South America, and Australia, tectonic phenomena and volcanic activity have played a very important role in the diversification of the savannah vegetation in the Rift Valley.
[Photo: Clive Jones / Natural Science Photos]
238 The Masai respect their livestock and the wild animals, as is common in stockraising peoples. They neither hunt nor eat the meat of their own livestock, except on special occasions such as the celebrations they hold to protect their herds from some lion or leopard or as a ritual show of bravery by young warriors. The austere monotheistic Masai religion worships the moon, the greatest manifestation of the goodness of their god, Nkai, and the savannah grasslands, which they consider sacred. Rain is present in most rituals (for example their funeral rites and those related to war and peace). The Masai know many plants, which they use for very different purposes--to cure diseases, as stimulants, to flavor foods, or to repel insects. They also have a name for each and every grass that their livestock consumes. It is thus not fair to say the Masai and their herder culture has degraded and overexploited their environment out of ignorance. It was the whites who, by confining the Masai and their herds in reserves, have introduced a major factor throwing out of balance the relationship between this savannah people and their savannah environment.
[Photo: Purdy & Mathews / Planet Earth Pictures]
239 The preferred habitat of the hippopotamus (Hip-popotamus amphibius) is deep bodies of fresh water with thick reeds and grasses on the banks, though it sometimes enters the brackish waters in river mouths (see also photo 134). During the rainy season, many temporary shallow lakes form allowing it to spread out into a larger area than in the dry season, when it is restricted to the permanent bodies of water. This artiodactyl swims very well, even underwater. When it submerges, it closes its slit-shaped nostrils and its ears. Normally it stays underwater for between three and five minutes, but it can definitely stay under longer--up to half an hour.
[Photo: Jonathan Scott / Planet Earth Pictures]
240 The inhabitants of the villages on Komodo Island, Indonesia, live almost exclusively from fishing, especially among the reefs and in the shallows around the island, where fisheries are richest. Agriculture and stockraising have started to develop, diversifying the islanders' sources of subsistence. The villages are still typical Strait fishing villages with beached boats and houses built on stilts to keep them above the highest tide.
[Photo: C.A. Henley / Auscape Intenational]
241 For a long time, the Komodo dragon (Varanus komodoensis) was thought to be a mere legend, but in 1910 an officer of the Dutch colonial army in Indonesia was ordered to go and investigate it. The same year the first two specimens of the species were caught, and it was described and classified in 1912. The Komodo dragon is the largest member of its family (Varanidae, the monitor lizards) and the largest of all living lizards. The monitor lizards are found throughout Africa, in southern Asia, and especially in Oceania. The different species of monitor lizard differ mainly in their size and color, as they are all very much the same shape. The Komodo dragon is carnivorous, and its flat teeth are triangular in cross-section, unlike other monitor lizards, which have conical noncutting teeth. It bites out chunks of flesh from its victims, which it swallows, bones, and all, and digests with its powerful gastric juices. When it is not eating, it hides or sleeps inside a burrow that it digs near the dry river beds. The females use the same holes to lay their eggs, usually 20-30 eggs in each clutch.
[Photo: Cyril Ruoso / Bios / Still Picture]
242 A fish-drying stall in a fishing village on Komodo Island. Most fishing is in the reefs around the island and is more a subsistence activity than a commercial one. In terms of large-scale fishing, the inhabitants of the islands of the South Pacific--including the islands of the Sunda Archipelago--did not start to exert their rights over their fisheries until 1977. This was possible after the decision by the member governments of the South Pacific Forum to define their 200 nautical miles offshore limit. Each island nation obtained the rights to exploit the marine resources in its territorial waters, and, later, after the creation of the South Pacific Forum Fisheries Agency, quotas could be negotiated on the basis of rights and licenses for fisheries exploitation by huge foreign fleets. In 1991, the agency also reached an agreement with Japan to ban drift nets in the Pacific. Komodo Island, a natural reserve with an exceptionally diverse landscape, has found a further source of income in tourism, but its management plans include the continuation and growth of traditional fishing.
[Photo: C.A. Henley / Auscape International]
243 The wardens on the Komodo Reserve use long forked sticks to keep the Komodo dragons away from the tourists. (The lizards approach the flesh that has been left to attract them for the tourists.) The reserve's administration is very interested in protecting the reptile, as it is the island's greatest tourist attraction, and this has led to the stabilization and even a slight increase in its numbers.
[Photo: Jean-Luc Petit / Gam-ma]
244 Eucalyptus (Eucalyp-tus) are abundant in Aus-tralia's savannahs. Nearly all of the more than 600 species are native to Aus-tralia. This photo of the flowers of the woollybutt (E. miniata) was taken in Kimberley, Western Australia. The many species of eucalyptus have colonized almost every habitat, including savannahs and even deserts, where they can only survive next to watercourses. The evolution of the eucalyptus in the savannahs has been governed by three main factors: aridity, soil characteristics, and fire. Dry climates and fires are often associated with each other; the eucalyptus have thus adapted to recurrent fires and to low, irregular rainfall. In addition, these trees have developed mechanisms to live in infertile soils. One such mechanism is an internal system to reuse nutrients or retain phosphorus, as most Australian soils are poor in nutrients.
[Photo: Rex Morrison / Aus-cape Intenational]
245 The ochre rock paintings of the Australian Abo-rigines, such as the one shown in this photo taken in Napier Downs Station, played an important role in the daily and religious life of the first settlers of Australia. When a tribe occupied a given zone, it took responsibility for maintaining the paintings and fulfilling the associated religious obligations. The paintings served different purposes. Some of them were sited where religious ceremonies were held and represented legendary heroes, while others represented now-extinct animals. The Aborigines of some areas of Australia believed that drawing an animal meant they would catch more of them; drawing was thus a way of obtaining goods or foreseeing their abundance. Whatever interpretation is given to rock art, it undeniably gives a unique insight into the lives of the Aborigines in the past, when they were dependent on hunter-gathering but still did not cultivate crops. Australia is full of Aboriginal paintings, but rock art is especially abundant in certain areas. The Kakadu National Park contains two impressive examples, Nangalawuru and Lein-chhardt. They are about 10,000 years old and relatively well-preserved, despite erosion and the cracking of the rocks. Many new items of rock art have recently been discovered in the Kuring-gai National Park.
[Photo: D. Parer & E. Parer / Auscape International]
246 The fauna of the Kim-berley savannahs includes Gould's bat (Chalinolobus gouldii), also found on Tas-mania, the Norfolk Islands, New Caledonia, and the Australian mainland. This bat hangs from the foliage of the trees, within a hole in a trunk, or in caves, mines, or tunnels, with its wings extended. Like most other insect-eating bats, it sleeps during the day and only sets off to hunt at sunset. The distinctive features of the bats of this genus include fleshy outward-projecting lobules on either side of its mouth, glands embedded in its short, broad nose, and a coat of chocolate brown, sometimes with reddish shades.
[Photo: Jean-Paul Ferrero / Auscape International]
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|Publication:||Encyclopedia of the Biosphere|
|Date:||Mar 1, 2000|
|Previous Article:||Tusks and horns.|