PART 6
HOW IS BIODIVERSITY MONITORED AND PROTECTED?



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 225
BioDiversity PART 6 HOW IS BIODIVERSITY MONITORED AND PROTECTED?

OCR for page 225
BioDiversity Product of a butterfly farm near Wewak, Papua New Guinea. Bird-wing butterflies are grown on vegetation planted by a farmer on steep slopes near his village. Photo courtesy of Noel D.Vietmeyer.

OCR for page 225
BioDiversity CHAPTER 26 MONITORING BIOLOGICAL DIVERSITY FOR SETTING PRIORITIES IN CONSERVATION F.WILLIAM BURLEY Senior Associate, World Resources Institute, Washington, D.C. Identifying the elements of biological diversity and monitoring their changes through time is a daunting task. Biologists have long recognized that the full array of biological diversity will never be known completely—that is, not all species and ecosystems will be identified, named, cataloged, and studied in any detail before many of them are lost. For example, it is likely that there are many more than 10 million species living today. Only 1.4 million of these have been described and named, and a tiny fraction of them have been studied thoroughly for potential use by humans. Ecosystems also vary greatly in size, composition, complexity, and distribution, and it is not uncommon for ecologists to differ in describing and defining them. For example, despite many studies by vegetation ecologists and biogeographers in the United States, today there is no single, agreed-upon vegetation classification that can be used by the federal land-management agencies or by the many state and private organizations that could productively use a national classification scheme. All this makes the work of systematically conserving species and ecosystems more difficult. It presents a real problem when we try to determine how well various ecosystems are protected or represented in the global, national, and state systems of protected areas (Harrison et al., 1984). THE GAP ANALYSIS CONCEPT To tackle this problem, conservation biologists for years have intentionally or unwittingly used the process called gap analysis to establish short-term and longer-term conservation priorities. The concept is deceptively simple, if not simplistic:

OCR for page 225
BioDiversity within a particular country or region, first identify and classify the various elements of biological diversity in several ways. Then examine the existing and proposed systems of protected areas and other land-management units that help conserve biological diversity. Finally, using various classifications, determine which elements (e.g., major ecosystems, vegetation types, habitat types, species) are unrepresented or poorly represented in the existing system of conservation areas. Once this is known with reasonable precision, priorities for the next set of conservation actions can be established. The process continues indefinitely, and the conservation system is refined as land use changes and as better information about the distribution and status of species and ecosystems is obtained. In practice, this process usually entails comparing and analyzing many different sets of information by using maps or computers to identify, for example, the gaps in coverage. Many countries have begun this process, but unfortunately, very few have attempted it in a thorough, systematic fashion with defined conservation objectives. Notable exceptions include Great Britain, Peru, Australia, and South Africa (Specht et al., 1974). The example from Australia illustrates the process well. By the mid-1970s, there was an adequate description of the major vegetation types found throughout Australia. A comprehensive review of the various park and reserve systems was begun to determine which vegetation types were already represented and seemingly adequately protected. The thoroughness of this effort varied considerably from state to state, but by the late 1970s and early 1980s, it was becoming possible to make more objective statements about which vegetation types were poorly represented in the national and state systems and therefore which ones needed conservation attention first. The state of Queensland has taken this broad-scale analysis one step further (Sattler, 1986). The Queensland National Parks and Wildlife Service recently completed mapping the vegetation of Queensland’s 90 national parks, environmental parks, fauna reserves, and scientific reserves larger than 1,000 hectares, and it now is analyzing gaps in the representation of vegetation types by protected areas. As these are identified, steps will be taken to protect or otherwise conserve good representative examples of the highest-priority vegetation types (Sattler, 1986). AN UNDERLYING CONCEPT An important concept underlies the gap analysis process: by ensuring that all vegetation types are well represented in a system of conservation areas, it is assumed that much if not most of the biological diversity (species and ecosystems) will be protected. Systems in practice verify this, e.g., in much of the United States, Australia, and Europe, but in addition, special efforts must be made to ensure the protection of particularly critical species and ecosystem types. Debates continue to rage among biologists about the minimum critical sizes of populations and ecosystems that are necessary to conserve the biota over the long term. A very practical question emerges from these debates: should a particular ecosystem type already represented in the system of conservation areas be better represented, or should the next conservation effort be aimed at conserving other

OCR for page 225
BioDiversity ecosystems that are either unrepresented or not adequately represented? All these considerations and unanswered questions in conservation biology do not obviate the need for gap analyses in all regions and countries, however, because inevitably we must have a good information base on which to base better conservation decisions. Gap analysis exercises similar to the one for Australia mentioned above have been undertaken in other countries. In Chapter 29, Huntley describes progress to date in several countries of southern Africa. A somewhat similar process is also being used to identify global priorities in plant conservation, as described by Williams and Lucas in Chapters 28 and 30, respectively. In the United States, no such countrywide analysis of ecosystems exists, except for several very preliminary studies using coarse classifications of ecoregions and the most general vegetation types. The federal agencies have never agreed on the methods to be used, but a nongovernmental organization, The Nature Conservancy, has made the most thorough state-by-state investigations using several vegetation classifications and all the species distribution data available. By developing a standardized methodology for all the states, the Conservancy is now able to make regional and preliminary national assessments of the most important gaps in ecosystem and species coverage, thereby establishing conservation priorities in a more systematic fashion than was previously possible. Chapter 27 by Jenkins describes this effort further. On the global scale, the International Union for Conservation of Nature and Natural Resources (IUCN) and the World Wildlife Fund have worked over the past decade to identify major conservation priorities. A biogeographic classification developed by Dasmann, Udvardy, and others was used to determine which major biomes and biogeographic provinces worldwide are relatively well represented in the global system of protected areas and where there are major gaps in the system (Udvardy, 1975). The analysis itself does not take into account the quality or level of management (and therefore the degree and quality of protection) of the conservation areas, but it has been useful to IUCN and others in helping to determine the allocation of program funds and to design conservation activities on a global scale and in particular regions. IUCN is carrying this global analysis further, and its Commission on National Parks and Protected Areas is coordinating a series of regional analyses to identify high-priority ecosystems and to recommend the establishment of additional protected areas (MacKinnon and MacKinnon, 1987). The next step in refining this process, however, is to do essentially the same type of analysis at the country and local levels. This is already under way in several Latin American countries. The Conservation Data Center (CDC) in Lima, Peru, for example, recently analyzed gaps in ecosystem coverage by overlaying biogeographic provinces, life zones, selected vegetation types, and existing and planned conservation areas. Although biologists in Peru have known for some time that the Andean cloud forests and coastal vegetation types were being decimated by human impacts and were important ecosystems to be conserved, the gap analysis done by the CDC revealed these priorities in a much more systematic, quantified way and identified particular areas that should be put under some form of protective management.

OCR for page 225
BioDiversity Unfortunately, however, most developing countries are not this far along in the process. This is ironic, because the cost and time needed to reach this level of data richness are not great, and a small team of biologists could pull together the necessary information in much less than a year. If every country in the tropics, for example, could generate this level of conservation information quickly, it would mean that more objective conservation priorities could be identified and made available for use not only by conservationists but also by land-use planners and development agencies. REFERENCES Harrison, J., K.Miller, and J.McNeeley. 1984. The world coverage of protected areas: Development goals and environmental needs. Pp. 24–33 in J.A.McNeeley and K.R.Miller, eds. National Parks, Conservation, and Development. Smithsonian Institution Press, Washington, D.C. MacKinnon, J., and K.MacKinnon. 1987. Review of the Protected Area Systems of the Afrotropical Realm. International Union for the Conservation of Nature and Natural Resources, Gland, Switzerland. 350 pp. Sattler, P.S. 1986. Nature conservation in Queensland: Planning the matrix. Proc. R. Soc. Q. 97:1–21. Specht, R.L., E.M.Roe, and V.H.Boughton, eds. 1974. Conservation of Major Plant Communities in Australia and Papua New Guinea. Aust. J. Bot., Supp. No. 7. Commonwealth Scientific and Industrial Research Organization, East Melbourne, Australia. 667 pp. Udvardy, M.D.F. 1975. A Classification of the Biogeographical Provinces of the World. IUCN Occasional Paper No. 18. International Union for the Conservation of Nature, Merges, Switzerland. 48 pp.

OCR for page 225
BioDiversity CHAPTER 27 INFORMATION MANAGEMENT FOR THE CONSERVATION OF BIODIVERSITY ROBERT E.JENKINS, JR. Vice President, Science Programs, The Nature Conservancy, Arlington, Virginia Everyone is beginning to recognize that biodiversity at all levels—gene pool, species, and biotic community—is important for many reasons and that it is being rapidly diminished by habitat destruction and other damaging influences resulting from human population growth, pollution, and economic expansion. No one seems to think that we can do anything effective to control the root causes soon enough to provide breathing space for the biota, so biological conservationists devote themselves to the use of techniques that are believed to be helpful in the context of a shrinking natural estate. All these techniques involve forms of triage, increasingly complex interventions, and decreasing margins for error. To conserve biodiversity in less and less space under greater and greater pressure requires that we have more and more knowledge. We need to know about the existence, identity, characteristics, numbers, condition, status, location, distribution, and ecological relationships between biotic species and biological communities or assemblages; their individual occurrences in the landscape; existing preserves and what they contain; the most important unprotected areas; related land ownerships; and sources of further information, among other things. With such knowledge we can select and design new preserves, improve existing ones, determine what sort of management is needed, establish priorities for ex situ conservation of species, monitor changing status, note restoration opportunities, and maybe even decide where we need to cut our losses and move on. Of course much of the basic information we would like to have has not even been collected in the field or, if collected, not yet developed into usable form. Kosztarab (1986, p. 23) estimated that “In the United States biologists have described only one-third of the living organisms and their developmental stages.”

OCR for page 225
BioDiversity Erwin (1982) has shown that the extent of our knowledge of the tropics is much more limited. From his collection of insects in tree canopies, he estimates that there may be 30 million species of organisms on Earth. This means that only about 5% have been described and classified at the species level, much less for all their developmental stages. Most of the undescribed organisms are invertebrates, fungi, and nonvascular plants. Kosztarab (Virginia Polytechnic Institute and State University, personal communication, 1986) believes it would take 50 entomologists 40 years just to describe the rest of the insects in the United States, not counting the work needed for additional collecting. It is implausible to think that we can mount a sufficient effort to amass this basic knowledge in time to have much bearing on the conservation of biodiversity. Fortunately, we can do a lot with the basic information already in hand. Before existing data can be put to use, they must be compiled from scattered secondary sources and repositories and organized into usable form. Accomplishing just this is a very complicated matter, much more so than can be realized without getting deeply into such matters as the details of system design, operational administration, and interinstitutional arrangements. The job would be quite challenging under ideal conditions, but in virtually all instances, this work has had to be carried out under severe financial constraints. Therefore, it is no wonder that many attempts to master the data compilation task have failed. The rest of this chapter describes an effort that seems to be succeeding. NATURAL HERITAGE DATA CENTERS The Nature Conservancy was established to conserve biodiversity by establishing natural area preserves. These preserves are selected and designed to protect examples of the widest possible spectrum of native ecosystems and species habitats. It was always clear that identifying the most important areas to be conserved was crucial to making the best use of limited resources. Therefore, gathering and organizing scientific information for conservation became one of the first orders of business. For many years, however, we were overmastered by the complexity of the task, and even the best of our efforts were essentially defeated by methodological flaws, limited duration of effort, underfunding, and similar problems. In 1974, in cooperation with the South Carolina Department of Wildlife and Marine Resources, The Nature Conservancy initiated the first of what are called State Natural Heritage Inventories. In this program, we finally brought together a sufficiently well-engineered mix of concepts and operational procedures for data gathering and management to successfully function as an efficient and effective tool for planning the conservation of biological diversity. The methodology used in that program has been continuously improved since 1974 and has become the most systematic, comprehensive, and widely used technology in existence for gathering and organizing the information needed for biodiversity conservation. (See Jenkins, 1985, for fuller explanations.) Natural Heritage Data Centers now exist in nearly every state of the United States, almost always as cooperative ventures between agencies of state government and the Conservancy (see Figure 27–1). Heritage inventory technology is also being

OCR for page 225
BioDiversity FIGURE 27–1 Distribution of the Natural Heritage Data Centers in 1986. used to help an increasing number of Latin American institutions to develop their own Centres de Datos para la Conservacion (CDCs), and requests for assistance in starting more such data centers have been coming in from other institutions all over the world. Collectively, the existing programs employ more than 250 biologists and have total annual operating budgets over $10 million. Each of these inventories used a highly standardized methodology, which provides some important economies in terms of system development and administration. In

OCR for page 225
BioDiversity other words, because of this standardization, the Conservancy has been able to develop, refine, and support systems on a very efficient basis, drawing new experience from all over, incorporating it into the central model, and propagating it throughout the network. Standardization also facilitates data exchange among the individual programs and permits higher order aggregation of data derived from many data centers. NETWORKING AND CENTRAL DATA BASES The standardization referred to above does not merely facilitate higher order aggregation of data, it virtually demands it. To optimize the effectiveness of the crucial bottom-up data collection of the individual centers, the Conservancy has gradually accumulated more and more data in a series of national data bases. We needed, for example, to have consistent taxonomic names for species to avoid the confusion brought about by locally used synonyms. We therefore kept central lists of names along with standard “element” codes for all rare and endangered plant and animal species being investigated by any state program. (An “element” is a species, a community type, or some other feature or phenomenon of special interest to conservationists.) We also began to accumulate national Element Manual Files on such species with information added and extracted by individual Heritage programs. We first thought that our central files would only accumulate information on a limited number of rare species. Since everything is rare somewhere in its range, however, we eventually discovered that we had at least some information on nearly every vascular plant and vertebrate animal species in the United States. We therefore went ahead and entered data on the rest of the species in these groups. We also have extensive information on species in other taxonomic groups, and these species- and community-type tracking data bases have become the most comprehensive compilations of such information in existence (Figure 27–2). Beyond standard taxonomy, there are many other data of common interest to more than one geographic area. To spare each data center the redundant effort of collecting and managing such data, we are dividing the labor by assigning lead responsibility for a given data item to one data center; results are then added to the central data bases, from which the other centers needing that same information can retrieve it. We have also found it useful to work this process in reverse, by undertaking special projects to add data obtained directly from national or regional sources for downloading to one or more individual data centers. From the beginning we have been compiling data from the National Museum of Natural History, for example, and then sending it back to Minnesota or Arizona where it came from. The central data bases are greatly facilitating this sort of procedure. Another reason for creating central data bases is the increasing need to compare information over wider geographic areas in order to gain a better perspective on the relative significance of conservation objectives and projects and to monitor status changes across a species’ or community’s entire range. In addition to the central data bases on North America, the Conservancy’s international office has made significant progress through a special Latin American

OCR for page 225
BioDiversity FIGURE 27–2 Data-processing procedure in the Natural Heritage program. Biogeography Project in assembling parallel data bases on the biota, ecosystems, and conservation areas throughout the rest of the Western Hemisphere. These central data bases are in Spanish and exchange information with the Latin American Conservation Data Centers. Since so many of the Latin American scientific data are located in U.S. repositories, the kind of top-down data repatriation from the central data base referred to above will be particularly helpful to the CDCs. Altogether, the network of local and central data bases, with its continually improving methods and procedures, has become a sort of machine for collective learning and retention of carefully winnowed facts. This network has been cumulatively amassing an immense body of knowledge with the capability of providing ever better insights about biological conservation needs and priorities. It is already being tapped as an important aid to decision making by a continually widening usership. APPLICATIONS OF THE DATA Following are some of the principal uses of these data: Facilitating continuing inventory. By organizing data well enough to tell what is and is not known, data needs can be targeted with precision. This is crucial in

OCR for page 225
BioDiversity TABLE 29–1 The Seven Centers of Endemism of the Afrotropical Realm, With Estimates of the Numbers of Seed Plant, Mammal (Ungulates and Diurnal Primates), and Passerine Bird Species in Each and the Percentage of These Endemic to the Unita     Plants Mammals Birds Biogeographic Unit Area (1,000 km2) No. of Species % Endemic No. of Species % Endemic No. of Species % Endemic Guineo-Congolian 2,815 8,000 80 58 45 655 36 Zambezian 3,939 8,500 54 55 4 650 15 Sudanian 3,565 2,750 33 46 2 319 8 Somali-Masai 1,990 2,500 50 50 14 345 32 Cape 90 8,500 80 14 0 187 4 Karoo-Namib 692 3,500 50 13 0 112 9 Afro-montane 647 3,000 75 50 4 220 65 aAfter MacKinnon and MacKinnon, in press.

OCR for page 225
BioDiversity TABLE 29–2 The Number of Seed Plant Species in Various Regions of the Worlda Biogeographic Unit No. of Species Area (1,000 km2) Species (per 1,000 km2) Tropical Africa 30,000 20,000 1.5 West Tropical Africa 7,300 4,500 1.6 Sudan 3,200 2,505 1.28 Southern Africa 22,977 2,573 8.93 Cape Floral Kingdom 8,504 90 94.49 Brazil 40,000 8,456 4.73 Peninsular India 20,000 4,885 4.09 Australia 25,000 7,716 3.24 Eastern N. America 4,425 3,238 1.37 aAfter Gibbs Russell, 1985. The flora of the Afrotropical realm probably includes some 40,000 species, the richest component of which is found in southern Africa, especially in the Cape Floristic Kingdom, one of the six major floristic divisions of the world’s flora defined by Good (1974). The magnitude of the floristic richness of southern Africa is indicated in Table 29–2, which provides data for a wide range of regions. The 8,500 species of the Cape flora are compressed into an extremely small area. The change of species composition from one patch of vegetation to the next is very high—two sides of the same valley may differ by 45%, adjacent large areas may share less than 40% out of more than 2,500 species. Such rapid changes in floristic composition are unknown elsewhere, not even in the Indo-Malayan rain forest (Kruger and Taylor, 1979). The Cape Peninsula, only 470 square kilometers in area, possesses 2,256 indigenous species—more than half the flora of eastern North America. The unique floristic richness of the Cape is unfortunately matched by unusually serious threats to its survival. A detailed 10-year survey of the conservation status of southern Africa’s 23,000 species of plants indicates that some 2,373 are threatened. The Cape Floristic Kingdom, occupying less than 4% of southern Africa, accounts for 68% of the threatened species (Hall et al., 1984). Satellite imagery indicates that 34% of the region’s natural vegetation has been transformed by agriculture and other human activities. The second most serious threat to the small heathland shrubs characteristic of this region is the aggressive competition exerted by large, introduced woody weeds. In addition, an invasive ant has been found to suppress populations of the native seed-storing ants, thus exposing critical seed sets to predation by rodents or destruction by the intense fires that characterize these Mediterranean-climate shrublands. The distribution of Afrotropical birds is rather different from that of the patterns of floristic richness. A recent analysis of the distribution of 1,595 species of Afrotropical birds indicated fairly clear correlation between bird diversity and rainfall, vegetation, and other factors in the present environment. But many species of forest birds displayed distribution patterns that could best be interpreted in terms of past climatic and habitat conditions (Crowe and Crowe, 1982). These somewhat anomalous distributions indicate the occurrence of what are known as Pleistocene

OCR for page 225
BioDiversity refugia—sites that would have escaped the dramatic environmental changes that took place during repeated ice ages. They are not only sites of species richness and endemism but are also the habitat islands of rare and threatened species. Of the 168 species listed in Threatened Birds of Africa and Related Islands, the ICBP/IUCN Red Data Book, 87 are forest species (Collar and Stuart, 1985). Many of these birds occur as isolated populations in widely separated montane forests. The most critically threatened group of these rare birds survive in the small patches of forest on Mount Moco in central Angola, more than 2,500 kilometers distant from similar but much larger forests in Cameroon, eastern Zaire, Tanzania, and the South African escarpment (Huntley, 1974). Pressure for timber and fuelwood on this 100-hectare remnant is severe—the rural peoples living on the cold mountain slopes have no alternative resources. The Great Lakes of Africa are the only massive freshwater bodies in the tropics. They are comparable in size to the North American Great Lakes but are much older. The African lakes harbor the world’s richest palustrine fish faunas, one family of which (Cichlidae) provides the supreme example of vertebrate evolution within geographically isolated communities—upwards of 900 species—far more spectacular than that described and immortalized by Darwin in the 13 species of Galapagos finches. Table 29–3 indicates the levels of species richness and endemism in the three largest African lakes. There are probably more than 1,100 species of indigenous fishes in these lakes, compared with less than 160 species in the much larger North American lakes. Not only are these fishes of immense ecological, evolutionary, and conservation interest, they also support a major traditional fishery. This fishing culture, and its socioeconomic fabric, is now being threatened by the introduction of sophisticated and capital-intensive fisheries based on Nile perch, an introduced species (Coulter et al., 1986). This piscivorous species was introduced into the northern part of Lake Victoria in 1960 in a well-intentioned but shortsighted effort to improve the commercial fishing industry. It has rapidly expanded its range in the lake at the expense of the endemic species. Massive changes in the abundance and distribution of these endemics are occurring, and it is estimated that up to 30 species have already become extinct. This is probably the highest rate of human-induced extinction of vertebrates yet recorded. The tragedy of the situation is that a vast number of the species currently threatened with extinction have not yet been collected, classified, and named. TABLE 29–3 The Great Lakes of Africa: Area, Fish Species Richness, and Endemisma     Cichlid Other Families Lake Area (km2) No. of Species % Endemic No. of Species % Endemic Victoria 68,000 250 99 38 42 Tanganyika 33,000 165 99 75 70 Malawi 30,800 500 99 45 63 aFrom Coulter et al., 1986.

OCR for page 225
BioDiversity APPROACHES TO THE CONSERVATION OF BIOTIC DIVERSITY IN AFRICA The spectacular diversity of landscapes and biota in Africa is not matched by the human and financial resources needed to protect and manage this heritage. It is therefore essential that available skills and funds be directed to sites of the highest conservation priority. An objective system of assessing priorities in relation to clear and unambiguous goals is needed. Within the context of the goals of the World Conservation Strategy, the specific objective of in situ biodiversity conservation in Africa might take the following form: To establish a minimum set of protected areas that provides for the preservation of the full range of African ecosystems and their biota, including marine and coastal species and systems. Some of the steps to be taken to reach this objective include: the development of a hierarchical series of biotic classification systems (from continental to regional to local scales); the assessment of the current level of protection given to each element of these classifications; the identification of gaps in the protected area network within a ranked listing of priorities; and the mobilization of the funds and manpower needed to incorporate these areas within the network. These needs will now be examined in the light of African examples. BIOTIC CLASSIFICATION SYSTEMS The first need in any review of biotic resources is information on the types, numbers, and distribution of the plants and animals to be found in the area under study. Such information is best synthesized within major vegetation and plant-geographic units. UNESCO has recently published a comprehensive review of the vegetation of Africa (White, 1983) and a detailed map at a scale of 1:5 million, which is of tremendous value in assessing the protected area cover of biota at a continental scale. Numerous regional and national vegetation classifications and maps that are also available in other publications permit analyses at finer resolution. But the complexity of biotic communities and the distribution of plants and animals require that much additional information be made available. The small, but species-rich communities of lakes, wetlands, rivers, estuaries, coastal dunes and mangroves, inselbergs, and escarpments, and many other specialized habitats are seldom included at the scale of even national vegetation maps. Conservation plans that ignore these communities will miss much of a region’s biotic richness (Clarke and Bell, 1986). A more complex problem relates to endemism. Centers of endemism are seldom reflected in distinctive and mappable vegetation types, yet they are of considerable conservation interest. Of greater concern is the fact that centers of endemism can

OCR for page 225
BioDiversity only be revealed through exhaustive floristic analysis, a task that has been accomplished for very few species groups in Africa. Even in South Africa, which has benefited from more than 200 years of biological survey, new centers of endemism of considerable importance are only now being detected. ASSESSING THE ADEQUACY OF CURRENT PROTECTED AREA COVER During the past 30 years, the International Union for the Conservation of Nature and Natural Resources has developed a comprehensive data bank on the protected area systems of the world. It has recently completed a detailed listing of all protected areas of the Afrotropical realm, providing exhaustive information on the geographic, faunal, floral, and management attributes of each of some 620 protected areas greater than 50 square kilometers in the realm (IUCN/UNEP, 1987). This data base served as the foundation for the review of Afrotropical protected areas undertaken by MacKinnon and MacKinnon (in press), whose analysis indicates that 4.7% of the realm falls within protected areas totalling 949,500 square kilometers, considerably larger than the State of Texas. By comparing the total area of each mapped vegetation unit with that falling within protected areas, they found that only one of the seven major centers of endemism of the Afrotropical realm has more than 10% of its area protected. The other six centers have between 3.6 and 7.0% of their area within national parks and reserves. Even at the extremely coarse scale of resolution afforded by this analysis, the finding that as little as 3.6% of the biotic resource is protected gives cause for concern. On closer inspection, the situation is even worse—many of the so-called national parks in Africa are little more than yellowing documents in government archives. The Giant Sable Integral Nature Reserve in central Angola is occupied by more than 20,000 peasant farmers, several trading villages, and until guerilla activity prevented it, extensive diamond prospecting. The Reserve has not seen a game ranger in 10 years. Factors such as the above necessitate a more objective evaluation of the effective protection afforded each biogeographic unit and protected area. In recent years, a variety of scoring systems have been proposed. These systems take account not only of the relative area protected but also of the effectiveness of government action to provide long-term security to the area (Clarke and Bell, 1986; Cumming, 1984). MacKinnon and MacKinnon (in press) developed a scoring system based on the size, protection objectives, and management effectiveness reported for each site. These data were then summarized by biogeographic unit and weighted for the number of distinct habitats and altitudinal ranges represented within the conservation network. Assessment of priority for action was based on the principle that action should be taken where it could have the best effect, not on lost causes—an all too common failing of conservation efforts based on sentiment rather than science. At a finer scale of resolution, an analysis of the protected area cover of 189 vegetation units in 10 southern African states demonstrated the existence of major deficiencies in many of the 24 major vegetation divisions recognized (Huntley and Ellis, 1984). The most seriously threatened systems included the lowland forests

OCR for page 225
BioDiversity of Angola and Mozambique and the Highveld grasslands, lowland fynbos, and succulent karoo of South Africa. All these systems face rapid reduction due to agricultural development or exploitation of timber resources for foreign exchange or fuel wood. To assess the adequacy of the protected area cover of 15 communities in the exceptionally rich communities of the lowland fynbos (Cape heathlands), Jarman (1986) made use of 1.25 million maps prepared from satellite imagery. More than 69% of this species-rich vegetation formation had already vanished under urban, industrial, and agricultural development, and 21% of the 8,955 square kilometers still in a seminatural state had been invaded by alien woody plants. A working group of over 40 researchers, administrators, and land owners participated in a 3-year study of the remnant patches of lowland fynbos. The survey identified 153 sites of conservation value and ranked them according to a formula that incorporated quantified attributes such as the rarity of the vegetation type, habitat diversity, total species richness, and the number of threatened plants found on the site. The rating was weighted in terms of the size and shape of the site and its distance from other protected areas and the degree to which the site had been transformed by introduced woody plants or other forms of disturbance. The conservation merit ratings ranged from 13 to 80 out of a possible 100. Only 5 out of 32 sites with a rating above 50 were currently protected, whereas the majority of the other existing reserves had ratings below 30 and were considered either too small, too greatly disturbed, or too low in biotic richness to merit inclusion in a costly protected area network. The study was probably the most detailed of its kind ever undertaken in Africa; indeed, the variety and quality of data available for the analyses are unlikely to become available elsewhere on the continent for many years. The significance of the results lies in the finding that even in an area of considerable financial and manpower resources, past decisions on the selection of sites for protection have been wholly inadequate to meet biological conservation needs. IDENTIFYING GAPS IN THE NETWORK The results of surveys of protected area cover based on vegetation maps can only provide the first step in the process of identifying gaps in the network. Much of the diversity of African ecosystems lies in communities that are too restricted or too narrow or patchy in their distribution to be included in the analytical approaches described in the last section of this chapter. Rivers, wetlands, and coastal ecosystems fall in this category. As a consequence of this, they have been largely ignored by African conservation agencies. During the last 10 years, long overdue attention has been devoted to these ecosystems in southern Africa. Some of the experience gained can be described here. Wetlands in the form of seasonally waterlogged grasslands (dambos) are a characteristic feature of the vast moist savannas of the central African plateau. Drainage of these dambos provides the only rich agricultural soils over vast areas, and much of these systems have been transformed into agricultural lands, dramatically reducing the habitat available to the vulnerable Wattled crane (Grus carunculata)

OCR for page 225
BioDiversity populations, which are dependent on these frequently burnt short grasslands. In South Africa, concern for the future of the Wattled crane has brought new emphasis to the conservation of the wetlands that support the remaining 100 pairs breeding in the country. Furthermore, 48% of the birds listed in the latest South African Red Data Book—Birds are grassland and wetland species (Brooke, 1984). Even more urgent, however, is the need to rehabilitate wetlands in the catchments of the country’s major rivers, which now carry up to 375 tons per square kilometer per year of soil lost from overgrazed rangelands and cultivated slopes. Despite the importance of wetlands, conservation efforts have ignored them because of difficulties in defining, identifying, and mapping them. These problems have now been overcome by the use of hydromorphic soils as the key indicator of wetlands (Begg, 1986). Maps of such soils are readily available in most African countries, and their identification on aerial photographs for detailed checking in the field is relatively easy. Because the soils retain their structural characteristics longer than their vegetation cover, it is also possible to obtain a rapid estimate of the rate of change in wetland systems. In the Tugela Basin of Natal, up to 34% of wetland communities have been destroyed in the past 50 years due to cultivation or overgrazing followed by extensive soil erosion. The most seriously neglected biotic systems in Africa are the tens of thousands of kilometers of streams and rivers that drain the continent. Even those rivers protected within national parks and reserves are subject to severe impacts from developments upstream or downstream of the protected section. Their narrow linear structure and diffuse spread make them difficult to contain within all but the largest protected areas, and detailed information on their biological values, degree of disturbance, and conservation needs are difficult to synthesize. They are, like wetlands, invariably ignored by conservation planners. During the last 3 years, considerable progress has been made in overcoming the difficulties of analyzing river conservation needs in South Africa. A computer-based expert systems technique developed by O’Keeffe et al. (1986) simulates the logic processes of river ecologists and converts the multivariate probabilities and diffuse intuitions of real-life situations into a simplified expression of river conservation status. The advantage of the system is that the complex calculations of interrelationships are handled by the computer, but the flexibility to take account of unusual situations is retained. A wide range of attributes are included in the system framework, and the users enter the best-available information on each of these, ideally within a workshop situation where the researchers, conservationists, and planners can pool their resources. Because each river is different and, therefore, all attributes do not always apply in the same way, a number of rules are included in the program to interrelate attributes or modify their effect. The system is designed to assess whole river systems, individual rivers, parts of rivers, or points in a river. The extent of the assessment must be defined by the user beforehand. Obviously, the assessment of a whole river system will be performed at a coarser resolution than that for a small tributary. The flexibility of the system, allowing successive levels of data to be added as knowledge improves, makes it especially useful in Africa, where few river systems

OCR for page 225
BioDiversity are adequately documented. The system has been developed for use on personal computers and is thus within the reach of most government agencies in Africa. MONITORING THE SYSTEM The dynamic nature of African ecosystems was mentioned at the beginning of this chapter. Continent-wide changes in the distribution of forests, savannas, grasslands, and deserts have occurred during the last 18,000 years due to major climatic events. San bushmen monopolizing isolated desert waterholes, iron-age communities deforesting coastal woodlands, and honey-gatherers burning moist savannas have induced subtle but significant fluxes in the distribution and abundance of plants and animals over the past 1,000 years. More recently, the changes brought about by both colonial and independent governments have been more extensive and less benign. Superimposed on these latter changes have been oscillating dry and wet rainfall patterns with intervals of 10 to 20 years. Any attempt to monitor the status of species and ecosystems must be cognizant of such fluxes. Conservation biologists in Africa seldom occupy research posts for more than 10 years, and few remain at a given station for more than 5 years. Their observations are therefore of limited generality and frequently result in misleading rather than accurate predictions of a system’s behavior. Nature is often counter-intuitive, and the obvious management response to a problem is not always appropriate—it may even produce an effect directly opposite to that intended (Caughley and Walker, 1983). Research is needed to develop a predictive understanding of ecosystem structure and functioning in response to environmental changes and must be linked to monitoring systems that measure the direction and rates of these changes and responses. There is extensive literature on the philosophy and technology of environmental monitoring. In Africa, much of this is irrelevant. What monitoring is being done varies tremendously in spatial and temporal scales and in duration and precision. Even where detailed long-term studies have been undertaken, few of the results are amenable to statistical analysis and valid interpretation due to faults in their experimental design (O’Connor, 1985). There are simply no reliable sets of data on some of the most critical issues in biotic diversity, such as the reduction of moist forests and the floristic impoverishment of arid lands. The need for a carefully planned international program of biotic diversity analysis and monitoring in Africa is an urgent priority. Without a reliable data base, cost-effective conservation measures cannot be planned. A few examples of successful monitoring activities suggest possible lines of approach. At continental and regional scales, Red Data Books (RDBs) of plants, animals, and habitats are beginning to provide a valuable first approximation to the monitoring of biotic diversity (Anonymous, 1985). The accuracy and detail of information on many species in these lists are inadequate, but the mere publication of these data leads to critical review and improvement. The 1976 RDB on South African birds was cited in more than 150 papers within 8 years of its publication, and the latest edition (Brooke, 1984) includes the reclassification of 37 of the

OCR for page 225
BioDiversity original listing of 101 species and adds 30 more. Similar rapid improvements of the data base on mammals, fishes, and plants have been witnessed in the new editions of these volumes. Although most of these changes in status reflect the inadequacies of the original data rather than real changes in the field situation, the existence of the RDBs triggered an upsurge of interest in monitoring rare species. This activity has been followed by the launch of annual counts of storks and cranes at a southern African scale; monitoring of all RDB bird species is now undertaken within a national bird atlassing project (Hockey and Ferrar, 1985). Perhaps the most ambitious and detailed monitoring project yet undertaken in Africa is that initiated in the Kruger National Park in South Africa in 1975. Following on 50 years of data collection on large mammal numbers and distribution, rainfall patterns, and fire occurrence, the current program includes a network of climate, vegetation transect, and fixed-point photographic stations plus detailed helicopter and fixed-wing aerial counts of 12 species of large mammals, estimates of forage and water availability, season and extent of controlled burns and wildfires, and other information, with a sampling scale of 4-square-kilometer units within the Park’s 19,853 square kilometers. The aerial and ground survey data are integrated within a series of computer programs, which provide a robust data base for the analysis and interpretation of large-scale patterns of change in savanna ecosystems (Joubert, 1983). Even more detailed monitoring of the dynamics of large mammal populations has been undertaken at Sengwa Wildlife Research Area in Zimbabwe, where the movements and social behavior of the elephant population have been tracked by radio telemetry for over a decade. The elephant study is supplemented by 20 years of detailed transect surveys of the habitat use of 15 other species of mammal. The Kruger Park and Sengwa projects, along with similar studies elsewhere in Africa, provide the practical experience and theoretical framework for much less sophisticated monitoring systems for implementation in countries with more limited resources. Ironically, the lessons learned in such extended and expensive exercises are seldom noted by expatriate conservation biologists sent to Africa. LESSONS LEARNED The review in this chapter is far too brief to provide more than a superficial treatment of the problems and progress in conserving biodiversity in Africa. A few key points arise from experience in this field over the past 20 years. African ecosystems are not as fragile and vulnerable as is popularly believed. Throughout their evolution, they have been subjected to enormous environmental pressures—including the hunter and the fire maker through the last few hundred thousand years. But current accelerated rates of change leave little room for complacency regarding the identification of real rather than perceived conservation priorities. Biotic diversity is not linked to the distribution of elephants, rhinos, and other so-called charismatic megaherbivores. The massive investment in conservation campaigns directed at these species does more for the souls of the donors and the

OCR for page 225
BioDiversity egos of the elephant experts than it does for biotic diversity, which is centered on less exciting communities of montane forests, Mediterranean heathlands, wetlands, lakes, and rivers. The analysis of the level of protection afforded mapped vegetation types is a valuable first approximation to evaluating the effectiveness of existing protected area systems. But attention must also be directed to centers of species richness and endemism and to sites of threatened species, which are seldom reflected in vegetation maps. RDBs of threatened plants, animals, and habitats are of considerable value in stimulating interest at a national level in issues of biodiversity conservation. The existence of highly sophisticated environmental monitoring systems in several African states offers experience and expertise to other countries that require simple but effective approaches to monitoring biodiversity. Expert systems based on the synthesis of available ecological principles and local knowledge offer tremendous potential in the development of objective decision rules for identifying conservation priorities in areas and on topics with limited expertise or data. With very few exceptions, knowledge of biotic conservation needs and priorities far exceeds the ability of African governments to implement conservation action plans. REFERENCES Anonymous. 1985. The plant sites Red Data Book. Pp. 3–24 in Plant Conservation in Africa. A Joint Session with the International Union for the Conservation of Nature. Association for the Taxonomic Study of the Flora of Tropical Africa. Begg, G. 1986. The Wetlands of Natal. Natal Town and Regional Planning Report. No. 68. Pietermaritzburg, South Africa. 114 pp. Brooke, R.K. 1984. South African Red Data Book—Birds. South African National Scientific Programmes Report. No. 97. Foundation for Research Development, Council for Scientific and Industrial Research, Pretoria, South Africa. 213 pp. Caughley, G., and B.Walker. 1983. Working with ecological ideas. Pp. 13–33 in A.A.Ferrar, ed. Guidelines for the Management of Large Mammals in African Conservation Areas. South African National Scientific Programmes Report. No. 69. Foundation for Research Development, Council for Scientific and Industrial Research, Pretoria, South Africa. Clarke, J.E., and R.H.V.Bell. 1986. Representation of biotic communities in protected areas: A Malawian case study. Biol. Conserv. 35:293–311. Collar, N.J., and S.N.Stuart. 1985. Threatened Birds of Africa and Related Islands, the ICBP/ IUCN Red Data Book. International Union for Conservation of Nature and Natural Resources, Gland, Switzerland. 761 pp. Coulter, G.W., B.R.Allanson, M.N.Bruton, P.H.Greenwood, R.C.Hart, P.B.N.Jackson, and A.J.Ribbink. 1986. Unique qualities and special problems of the African Great Lakes. Environ. Biol. Fish. 17(3):161–183. Crowe, T.M., and A.A.Crowe. 1982. Patterns of distribution, diversity and endemism in Afrotropical birds. J. Zool. 198:417–442. Cumming, D.H.M. 1984. Toward establishing priorities for funding and other international support for protected areas in Africa. Pp. 108–111 in Proceedings of the Twenty-Second Working Session of the Commission on National Parks and Protected Areas, Victoria Falls, Zimbabwe, 22–27 May, 1983. International Union for the Conservation of Nature and Natural Resources, Gland, Switzerland. Gibbs Russell, G.E. 1985. Analysis of the size and composition of the southern African flora. Bothalia 15:613–629. Good, R. 1974. The Geography of the Flowering Plants. 4th Edition. Longmans, London. 557 pp. Hall, A.V., B.de Winter, S.P.Fourie, and T.H.Arnold. 1984. Threatened plants in southern Africa. Biol. Conserv. 28:5–20. Hockey, P.A.R., and A.A.Ferrar. 1985. Guidelines for the Bird Atlas of Southern Africa.

OCR for page 225
BioDiversity Ecosystem Programmes Occasional Report. No. 2. Council for Scientific and Industrial Research, Pretoria, South Africa. 55 pp. Huntley, B.J. 1974. Outlines of wildlife conservation in Angola. J. S. Afr. Wildl. Manage. Assoc. 4:157–166. Huntley, B.J., and S.Ellis. 1984. Conservation status of terrestrial ecosystems in southern Africa. Pp. 13–22 in Proceedings of the Twenty-Second Working Session of the Commission on National Parks and Protected Areas, Victoria Falls, Zimbabwe, 22–27 May, 1983. International Union for the Conservation of Nature and Natural Resources, Gland, Switzerland. IUCN (International Union for Conservation of Nature and Natural Resources). 1980. World Conservation Strategy. Living Resource Conservation for Sustainable Development, International Union for Conservation of Nature and Natural Resources, Gland, Switzerland. Four-brochure set. IUCN/UNEP (International Union for Conservation of Nature and Natural Resources/United Nations Environment Programme). 1987. The IUCN Directory of Afrotropical Protected Areas. International Union for Conservation of Nature and Natural Resources, Gland, Switzerland. 1,034 pp. Jarman, M.L. 1986. Conservation Priorities in Lowland Regions of the Fynbos Biome. South African National Scientific Programmes Report. No. 87. Foundation for Research Development, Council for Scientific and Industrial Research, Pretoria, South Africa. 53 pp. Joubert, S.C.J. 1983. A monitoring programme for an extensive national park. Pp. 201–212 in R. N.Owen-Smith, ed. Management of Large Mammals in African Conservation Areas. HAUM Educational Publishers, Pretoria, South Africa. Kruger, F.J., and H.C.Taylor. 1979. Plant species diversity in Cape Fynbos: Gamma and delta diversity. Vegetatio 41:85–93. MacKinnon, J., and K.MacKinnon. In press. Protected Areas Systems Review of the Afrotropical Realm. International Union for the Conservation of Nature and Natural Resources, Gland, Switzerland. O’Connor, T.G. 1985. Synthesis of Field Experiments Concerning the Grasslayer in the Savanna Regions of Southern Africa. South African National Scientific Programmes Report. No. 114. Foundation for Research Development, Council for Scientific and Industrial Research, Pretoria, South Africa. 126 pp. O’Keeffe, J.H., D.B.Danilewitz, and J.A.Bradshaw. 1986. The River Conservation System, a User’s Manual. Ecosystem Programmes Occasional Report. No. 9. Council for Scientific and Industrial Research, Pretoria, South Africa. 17 pp. Udvardy, M.D.F. 1984. A biogeographical classification system for terrestrial environments. Pp. 34–38 in J.A.McNeely and K.R.Miller, eds. National Parks, Conservation, and Development: The Role of Protected Areas in Sustaining Society. Proceedings of the World Congress on National Parks, Bali, Indonesia, 11–12 October 1982. Smithsonian Institution Press, Washington, D.C. White, F. 1983. The Vegetation of Africa: A Descriptive Memoir to Accompany the UNESCO/ AERFAT/UNSO Vegetation Map of Africa. United Nations Educational Scientific Cultural Organization, Paris. 356 pp.