Malcolm Hadley is a biologist with the Division of Ecological Sciences. Unesco, Paris.
Note: This article is dedicated to Matuka David Kabala, Programme Specialist in Unesco's Division of Ecological Sciences, who had been invited to contribute to this issue of Unasylva before his sudden death in Paris on 5 February 1993. Among Matuka Kabala's accomplishments was his advocacy that the conservation of nature and natural resources was a legitimate and important target in technical assistance programmes. He did much to promote and put into practice the biosphere reserve concept in Africa.
Managing parks and protected areas in humid Africa: the work of Unesco's Man and the Biosphere Programme.
Lab night end early morning mists are critical for the survival of the dense tropical forests in the Mayombe region of the Congo
Over the past two decades, conservation scientists have been looking into ways of making conservation responsive to a fast-changing society. These changes, in African terms, include fast-growing populations; a changing socioeconomic situation, especially through urbanization; increasing demand on natural resources to meet basic needs; a changing environmental situation through industrialization; general climatic changes with increased droughts; and changes in political systems.
A review of the conservation approaches in Africa reveals an underlying need for approaches to broaden and accommodate uses of protected areas other than those for which only gate fees are paid. There seems to be a general consensus in contemporary thinking that a more open approach is the only solution, or else protected areas may be completely swallowed up by stronger and more popular interests. Put another way, conservation objectives must be balanced with development.
Biosphere reserves represent one such concept and tool (Di Castri and Loope, 1977; Unesco, 1984), with much of the underlying philosophy and characteristics of what have recently been called "integrated conservation and development projects" (Brown and Wyckoff-Baird, 1992).
Biosphere reserves are an innovative type of protected area which originated within Unesco's Man and the Biosphere (MAB) Programme in the early 1970s. As the name of the programme implies, the objective was, and indeed remains, to find a means of reconciling nature protection with human needs, and underpinning the whole with international scientific cooperation. The entry point for biosphere reserves, therefore, was essentially pragmatic and scientific.
Fully functioning biosphere reserves perform three main roles: i) conservation in situ of the diversity of natural and semi-natural ecosystems and landscapes; ii) the establishment of demonstration areas for ecologically sustainable land and resource use; and iii) the provision of logistic support for research, monitoring, education and training related to conservation and sustainability issues.
These functions are associated through a zonation system consisting of a core area or areas with minimal human disturbance. The surrounding area acts as a buffer for the core and accommodates more human activities such as research, environmental education and training as well as tourism and recreation. The outlying transition area serves as a liaison with the larger region in which the biosphere reserve lies, and promotes in particular the development concern with activities such as experimental research, traditional use or rehabilitation, human settlements and agriculture, etc. Efforts are made to develop cooperative activities with research scientists, landowners, farmers and local populations; hence, the management of this zone requires innovative coordination mechanisms.
A key additional dimension is that biosphere reserves are united globally into a network, coordinated through the MAB Programme. As of mid-1993, there were 311 biosphere reserves in 81 countries, representing a total surface area of 170 million ha. In Africa, there are 85 biosphere reserves located in 23 countries. The situation of individual biosphere reserves is variable. In some cases, the denomination of biosphere reserve has been added to that of an existing national park, with little change in emphasis or management philosophy (Hough, 1988). In others, a real attempt has been made to integrate the multiple functions and participatory approaches that are intrinsic to the biosphere reserve concept. In the following sections, experience and activities from a number of biosphere reserves in Africa are drawn on to provide insights of efforts for combining conservation, research and sustainable resource use in the tropical regions.
Rice and forests rather than rice or forests
In Mananara-Nord on the northeastern coast of Madagascar during the 1980s, the nocturnal aye-aye (Daubentonia madagascariensis), the most remarkable of Madagascar's femurs, was causing serious damage to coconut stands by eating the young fruits. Research in 1987 showed that deforestation by local people, who continued to clear and burn the rain forest to satisfy their requirements for rice, was displacing the aye-aye from its natural biotope. The problem was complicated by the fact that the aye-aye is protected by law as well as by local traditional beliefs.
In order to find sustainable and acceptable solutions to the problem, a group of scientists and foresters suggested taking an integrated approach to protecting the forest, beginning with finding ways to satisfy the priority needs of local populations. The MAB reserve approach was the framework identified to address the issue. In September 1987, Unesco organized a multidisciplinary seminar at Mananara to define the institutional, legal, technical and social requirements for the creation of Madagascar's first biosphere reserve. An international conference on the environment, held at Tananarive (Antananarivo) in 1985 (jointly organized by the World Conservation Union, the Madagascar Government and the World Wide Fund for Nature), and the preparation of a national environmental action plan influenced UNDP's decision to finance the Mananara Biosphere Reserve project, which was submitted by the Department of Water and Forests and supported at the international level by Unesco. The launching of the project in October 1988 was followed in July 1989 by a presidential decree establishing the Mananara Biosphere Reserve.
A zoning system, incorporated into the legislation and consisting of core national park areas (24000 ha) and peripheral development zones (116000 ha), manifested the concern to integrate the protection and development of the target populations into the project, with the final goal of ensuring better management of the area's natural resources.
Participatory research carried out at the beginning of the project indicated that local people had the following priorities: increased rice production and yields; diversification into small-scale stock rearing; improved health care aimed at decreasing mortality from malaria, diarrhoeal diseases and bilharzia; and support for education (the costs of running primary schools, except for teachers' salaries, have generally to be borne by parents). In the light of these identified needs, project operations have targeted native villages of tavystes (highland rice cultivators) and fishermen around the national parks, with operations in such sectors as agriculture, rural infrastructure, health, education, fishing, animal husbandry, women's organizations, research, conservation and adventure tourism. Practical achievements (Ramangason, 1993) have included an increase in rice yield from 1 to 3 or 5 tonnes per hectare in 22 sites; 56 projects on strengthening rural infrastructure (e.g. irrigation systems, rehabilitating schools and health centres); the establishment of four village libraries; the introduction of beekeeping in five villages; encouraging the use of zebus as draught animals in rice cultivation; and developing plant resources used in handicrafts. Fifteen research projects have ranged from understanding patterns of rural decision-making and social structure to plant and animal inventories and improved production systems.
The University of Tananarive provides the main scientific backing for the work at Mananara-Nord, whose philosophy might be encapsulated in the phrase "rice and forests", not "rice or forests". The approach taken has been to relieve pressure on the reserve's core by improving the living conditions of the area's rural population and modifying existing resource use practices, particularly rice cultivation and fishing. Education and awareness have also been emphasized as a means to stimulate the involvement of local communities and institutions in project planning and implementation. Experience gained at Mananara-Nord is reflected in somewhat similar schemes that are being implemented in four other areas situated in different climatic zones of the country: Bemaraha, Tulear, Andasibe-Montody and Ankarafantsika.
Addressing conflicts, sharing revenues
Amboseli Biosphere Reserve lies at the border of Kenya and the United Republic of Tanzania in a semi-arid area renowned for its diverse and numerous wildlife. It occupies about 300000 ha, although its exact extent has yet to be fully defined since it is intended to include all the range covered by the migratory wildlife population.
The core zone of the biosphere reserve is formed by Amboseli National Park (39200 ha), with buffer and transition areas merged into what are collectively called dispersal areas, owned by the local Maasai pastoralists. Over the past two decades, increasing human and cattle populations have exacerbated conflicts in resource use, with sharpened competition of cattle and wildlife for water and grass and increasing hostility by the Maasai to wildlife populations.
In 1990, the government disbanded the Wildlife Conservation and Management Department and, by act of parliament, set up the Kenya Wildlife Services, a semiautonomous parastatal organization with a mandate to run the parks in Kenya. Among the interventions introduced by this body is that of sharing the revenue collected from the park's entrance fees with the local people living adjacent to the park. So far, the revenue (25 percent of total gate entry fees), is being given in the form of community services (e.g. schools, health centres, water and cattle dips). Although the scheme was initiated only relatively recently (September 1991), its promise is reflected in a sharp decrease in Maasai hostilities towards wild animals, with the number of reported cases of speared animals dropping to almost zero (Nyakweba, 1993).
The field research station of the Institute of Tropical Ecology in Taï, Côte d'Ivoire
Buffer zone development and long-term ecological studies
The Taï National Park covers an area of 330000 ha in southwestern Côte d'Ivoire. It was established as a national park in 1972 and declared a World Heritage Site in 1982. It is the largest fully protected area in the Upper Guinea forest block and is often described as "the only area that is sufficiently large and secure to guarantee the survival of the numerous animal and plant species endemic to this region" (Sayer, Harcourt and Collins, 1992). Species such as the pygmy hippopotamus, Jentink's and zebra duikers and chimpanzees, rare elsewhere in the Upper Guinea zone, are comparatively numerous in Tail The World Conservation Union (IUCN) review of the protected area systems of the Afrotropical realm ranked the Taï National Park as the single highest priority area for rain forest conservation in West Africa.
Within such a perspective, the conservation threats to Taï are several, including increasing human pressure, illegal hunting, gold prospecting and confusion between the legally protected areas of the national park and the contiguous buffer zones and transition areas (Kouadio, N'Goran and Lauginie, 1992). The problems of the buffer zones at Taï National Park have been particularly contentious (Sayer, Harcourt and Collins, 1992). Some people feel that the buffer zone should be totally protected and should be a de facto extension of the park itself. Others see the highest priority as being the sustainable use of the buffer zone forest to meet the needs of local communities so as to relieve pressure on the central area.
Part of the research effort at Taï is geared towards identifying possibilities for improved buffer zone management in such domains as the economic potential of non-wood forest products and approaches to weed control in shifting cultivation. In addition to such targeted research, the Taï region has been the subject of many long-term ecological studies (Guillaumet, Couturier and Dosso, 1984; Vooren et al., 1992). One of these long-term studies has shed important light on hominoid evolution, such as the sexual differentiation in the use of tools, and has also thrown strong doubt on a traditional view among palaeontologists that humans are the only primates who hunt for meat in a highly organized group. These studies, on chimpanzee populations at Taï have been carried out since 1979 by Christophe and Hedwige Boesch of the Swiss Centre for Scientific Research. Sustained observations have allowed the Boeschs to compare the hunting strategies of chimpanzees in Taï with those of the same species in savannah woodland in Gombe-Stream National Park in Tanzania (studied by Jane Goodall) and in a more heavily wooded savannah in the Mahale Mountains National Park, about 200 km south of Gombe (studied since the mid-1960s by a team of Japanese biologists headed by Toshisada Nishida).
A comparison of this kind provides insights on the effect of habitat on hunting behaviour, and particularly the effect of forest conditions in favouring the emergence of cooperation and group hunting (Boesch, 1990). The chimpanzees of Taï differ from those of Gombe or Mahale in four main ways:
· Forest chimpanzees are more highly specialized hunters than those of the savannah.
· Forest chimpanzees are group hunters. In Taï 63 percent of the hunts observed involved a minimum of two individuals compared with 36 percent in Gombe and 24 percent in Mahale.
· A third crucial difference is that cooperation in hunting is the rule among forest chimpanzees whereas it is the exception in savannah populations. In Taï 63 percent of all observed hunts involved a minimum of two animals, each performing a different but complementary role. Some act as drivers, others may attempt a capture by pursuing the prey, another may block a possible escape route simply by sitting in the way, while all the others encircle the prey and wait in ambush for the animal to come to them.
· A fourth difference is that forest-dwelling chimpanzees share meat much more consistently than those that live in savannahs.
Forest-atmosphere interactions at Dimonika Biosphere Reserve
The 62000 ha Dimonika Biosphere Reserve in the Mayombe region of the Congo is one of a number of biosphere reserves in the humid tropics where long-term research is contributing to an understanding of the processes related to global climate change. Since the late 1970s, scientists from the Marien Ngouabi University in Brazzaville and the University of Toulouse have been carrying out long-term studies on atmospheric physics and canopy-atmosphere interactions in the Mayombe (Diamouangana, Cros and Kabala, in press). A 45 m high metallic tower is among the tools used in assessments of the role of submicronic particles (e.g. Aitken nuclei, radon) as tracers for understanding canopy-atmosphere exchange. These particles play a key function in the formation of mists at the end of the night, which are critical for the survival of the dense forests of the Mayombe during the dry season (average annual precipitation in central Mayombe is only about 1200 to 1400 mm, with a four- to six-month dry season and four months with an average rainfall of less than 10 mm).
Precipitation at Dimonika, as both rain and mist, is highly acidic. This is largely attributable to vegetation fires in the surrounding savannah and has resulted in a considerable and permanent alteration of atmospheric conditions. Associated work in the Congo on sources and sinks of methane and carbon dioxide has entailed measurements of methane flux in the flooded forest zone of the Congo River basin compared with dry soil in the Mayombe. Important methane emissions were measured in flooded lowlands where soil characteristics (neutral pH and strongly negative oxydo-reduction potential) favour the growth of methanogenic bacteria. This contrasts with the upland soils in the Mayombe, which constitutes a sink of atmospheric methane.
There has been some controversy in recent years over whether termites are a major source of methane. Research in the Mayombe has suggested diet as a key determinant: humus- and fungi-feeding termites produce large quantities of methane while wood-feeding termites emit very little. The explanation lies with the presence of symbiotic, methane-producing microflora in the intestines of the humus- and fungi-feeding termites.
Part of the work at Dimonika now contributes to a cooperative programme involving several African and European laboratories and focusing on the dynamics and chemistry of the equatorial forest atmosphere. Known by the acronym DECAFE (Dynamique et Chimie de l'Atmosphère en Forêt Equatoriale), the programme is sponsored by the French Ministry of the Environment and other bodies. It also contributes to the proposed Southern Tropical Atlantic Regional Experiment (STARE) being planned within the framework of the International Geosphere-Biosphere Programme (IGBP). aimed at investigating the source of trace gases, their atmospheric transport and the chemical processes in the atmosphere that lead to elevated levels of ozone, carbon monoxide and other gases over the tropical Atlantic.
Hunting and trapping game at Luki
Despite its nutritional importance, wildlife hunting in tropical forests (as opposed to the savannah areas of the tropics) has been largely ignored in terms of scientific study. Those interested in the "benefits" to be gained from tropical forests have concentrated almost exclusively on plant products. Only recently have biologists, applied anthropologists and those interested in human use of tropical forest resources begun to study hunting (Robinson and Redford, 1991) and the implications of hunting to seed dispersal and forest regeneration.
In the 33000 ha Luki Biosphere Reserve in southwestern Zaire, studies have highlighted the role of wildlife in the maintenance of the reserve's flora, as well as the uses made by local people of forest products such as medicinal plants and firewood. Populations in urban centres in the vicinity of Luki have tripled over the past 30 years and increasing needs and pressures are reflected in offtakes of wildlife, which are hunted and eaten locally and sold in local rural centres as well as at a dozen sales points along the Kinzan-Muvete-Materne road which crosses the reserve. An inventory of 248 animals on sale at 12 locations on eight days of observation from April to July 1991 indicated that 22 species of mammals, belonging to ten families, made up 90 percent of the commercialized animals. Extrapolation suggests that over 900 animals are exported to the towns every month; that is more than 11000 animals per year.
With such levels of offtake, it is scarcely surprising that hunters and sellers are reporting a drop in numbers. Pendje and Baya ki Malanda (1992) describe the seriousness of the present situation in Luki to those in policy and management. However, since hunting is such a lucrative business (a small forest ruminant may fetch ten to 20 times the monthly wage of an agricultural worker), the future prospects for wildlife populations in the vicinity of Luki - and their potential contribution to sustainable forest use might appear to be bleak.
In addressing such situations, a distinction perhaps needs to be made between hunting for direct consumption and local sale, and hunting for transport and sale in urban centres. For example, in Côte d'Ivoire. in areas opened by logging concessions, there had been a severe reduction of forest ungulate and primate wildlife populations. Wildlife regulations were drafted to allow subsistence hunting but to provide a strict control over the transport of bushmeat from forest areas to urban markets. The result has been a significant decrease in bushmeat offtake. Similar legislation has also been drafted in neighbouring Liberia.
"Biosphere reserves" is both a concept and a tool, which seeks to combine protection of biodiversity with sustainable development and with improved knowledge of the functioning of ecological systems and their potential uses. Two of the principal challenges that have been encountered in putting the concept into practice are those of involving local people as the driving forces for conservation and of using the insights from scientific research in schemes for economic improvement and diversification.
In Africa, as in other tropical regions, the process of setting up protected areas has too often been associated with the alienation of local people from their resources and the complete absence of public participation in conservation actions. Conservation actions are resented by inhabitants who see them as restrictions preventing them from attaining an acceptable standard of living and well-being [Ed. note: see article by Tchamie]. Park rangers tend to be viewed as agents of repressive action. In the last few years, however, in Taï and elsewhere, there has been a change of attitude on the part of the government authorities and cooperating non-governmental conservation bodies towards acceptance of participatory park management (Vooren, 1992).
Such changes in attitude took place in the late 1980s and early 1990s, in part as a result of the much larger incentives that have been made available by bilateral and multilateral agencies for promoting conservation in Africa. As argued by McNeely (1993), the climate now seems right for designing new approaches to conserving biodiversity that are built on the use of economic incentives and disincentives as well as the reduction of perverse incentives.
Changing behaviour typically requires reasonably comprehensive packages of direct and indirect incentives as well as disincentives, and McNeely (1993) provides a number of examples from various parts of Africa which illustrate how such systems of economic incentives and disincentives can work.
Intercropping of rice and tree crops near Mananara-Nord, Madagascar
An increase in bilateral and multilateral funding for conservation projects is being paralleled by an upsurge in interest for seeking out ways and means of managing tropical landscapes in order to ensure a perpetual stream of multiple products and services at a reasonable cost. The notion of a critical mass strategy (Muul, 1989; 1993) is among those that hold promise. Just as there may be a minimum habitat area and a minimum population size for the long-term conservation of a particular species, so a critical mass strategy may offer one way of convincing economic developers that the sum of sustainable activities can exceed the profits of the sum of many ongoing unsustainable activities. Such a strategy requires making full use of the range of products and resources that tropical landscapes can provide. It calls for scientific research and demonstration schemes that give concrete and practical short-term evidence of the value of diverse ecological systems in order to convince economic developers that much larger areas of tropical land than those currently planned need to be set aside for conservation purposes. To be attractive, the critical mass strategy needs to be comprehensible, convincing, concerted (i.e. focused on achievable goals) and cost-effective.
Progress has also been made in the past few years in providing the occasions and opportunities for indigenous African experts to gather and exchange experience on wildlife conservation among themselves, in contrast to earlier gatherings which tended to be dominated by people from the outside. The February 1990 regional training workshop on protected area management in Africa, held in Mweka, Tanzania, was one such meeting of Africans talking to Africans (Lusigi, 1992). There have been others at the subregional level for such areas as the African part of the southwestern Indian Ocean (Maldague, Kabala and Albignac, 1989), the humid tropics of central Africa (Kabala, Maldague and Mankoto ma Mbaelele, 1990) and the Sudano-Sahelian zone (Kabala and Le Berre, 1993).
Another challenge has been to find the correct mix in the research agenda, combining basic research with more targeted research focused on the design of appropriate management practices and systems. Again using Taï as an example, there are indications that this mix of ingredients can be achieved, with earlier work on ecosystem structure and function (Guillaumet, Couturier and Dosso, 1984) and long-term research such as that on the chimpanzee populations (Boesch, 1990) being complemented by research to support the activities of grassroots organizations in the area (Vooren, 1992). To the extent that the "process is the product", the involvement of local people in conservation actions and of researchers in buffer zone and transition area development can be considered critical ingredients in the integration of community development, scientific research and conservation. The biosphere reserve concept can contribute to such a process. The concept is not a fixed agenda for a given area (Kaus, 1993); rather it provides a basis from which to develop a workable management plan that is compatible with local customs and conservation interests specific to that area.
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