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The failure of biogeographers to convey the conservation message

2000; Wiley; Volume: 27; Issue: 1 Linguagem: Inglês

10.1046/j.1365-2699.2000.00370.x

1365-2699

Ghillean Τ. Prance,

Species Distribution and Climate Change

There have been many attempts by biogeographers to use their data for practical conservation through such methods as defining centres of endemism and of diversity and then preparing sites for conservation units. An example of this is the map of Amazonia produced by a large number of biogeographers for Conservation International (1991). Indeed that map has resulted in the establishment of a few new reserves such as the enormous Jaú National Park in the Rio Negro region of Brazil. Recently a number of computer programmes have been produced to analyse biogeographic data for the purpose of conservation or placement of reserve, for example Worldmap ( Vane-Wright et al., 1991 ; Williams et al., 1991, 1996 ). In spite of these efforts from biogeographers around the world who are studying many different temperate and tropical ecosystems, the destruction of habitat is continuing, often at an accelerating pace. At the same time politically minded conservationists have produced the Convention on Biodiversity and a host of other legislation and, although there have been many conferences and debates following on from the Convention, the loss of species is continuing unabated. If we want there to be organisms to study in future and perhaps even a future for our own species, the many fields, including biogeography, that have entered into the conservation debate must work harder to promote the cause. Even in an age where biodiversity has become a well-known term, we are not getting the message about the importance of biological species to the politicians and industrialists who have the power to enact change. The challenge for the new millennium is to get our data much more widely beyond the pages of this most excellent Journal and in a format that can be readily understood by the layman. Many recent reports continue to document habitat destruction around the world (e.g. FAO, 1997; Salim & Ullsten, 1999). In tropical Asia only 32% of the potentially forested areas remained forest covered in the mid 1990’s and only 6% still contains undisturbed primary forest. Africa has lost 50% of its forested area and from 1980 to 1995 lost 15% of its forest, the highest rate in any region (FAO, 1997). Latin America and the Caribbean region was not far behind with a loss of 9.7% of its remaining forest during the same time period, which amounted to about 5.3 million hectares ( Salim & Ullsten, 1999). This loss was largely due to direct deforestation for projects of short duration that could not be sustainable in the medium or long term. The destruction in the biogeographers paradise of Madagascar is most alarming. In that country only 23% of the original vegetation remains. All the various humid and arid biomes have suffered destruction as natural vegetation is replaced by agriculture and paddy fields ( Du Puy & Moat, 1996, 1998). Island ecosystems, another favourite pasture for biogeographers, have really suffered badly and species have become extinct at an alarming rate in such places as the Mascarenes, St Helena, Juan Fernández or Hawaii. In the latter at least eighty-six native species of plants and many of the native birds have become extinct since western civilisation settled there. Many more Hawaiian species of plants and animals are on the brink of extinction. One of the conclusions of the recent report of the experts on the World Commission on Forests and Sustainable Development ( Salim & Ullsten, 1999) was that ‘the world’s forests are being cut at such a rapid rate that if action is not taken soon, we risk undermining their vital functions in maintaining a habitable planet’. Biogeographers are familiar with the problem, but what are we doing about it? A huge amount of biogeographical data lies hidden and of no use to conservation in monographs of many different types of organisms. Relatively few, but fortunately an increasing number of monographers are extracting the biogeographic data in their monographs either to develop biogeographic theories or to apply to conservation. It is the latter that this essay seeks to promote further. The most used concepts have been the application of biogeographical data to define centres of diversity and of endemism which are not necessarily the same (e.g. Brown, 1987; Prance, 1987). The Worldmap programme ( Williams et al., 1991, 1996 ) has been developed specially to identify and prioritize both centres of diversity and of endemism depending upon which algorithm is chosen. Worldmap has been used for a wide range of organisms from many areas of the world and at different scales. These analyses are furnishing most useful information for conservation. There have been many publications using Worldmap data, but have the significant conclusions reached the people who could make use of them for conservation or sustainable development? The Worldmap programme is only one of many new applications of methods using modern information technology. This has added value both to theoretical biogeography and to its practical application. Once such method that is being much used for conservation planning is Geographical Information Systems (GIS). For example, GIS is being employed extensively by the World Conservation Monitoring Centre in Cambridge an organisation that is to some extent succeeding in getting biogeographical information out to the broader world. At the Royal Botanic Gardens, Kew we have been able to overlay many physical aspects of the Madagascan environment such as geology, rainfall, soil, altitude with the known distributions of plants ( Du Puy & Moat, 1998). This has been used both to predict where else a species is likely to be found to plan better field work and also to analyse the efficacy of the existing conservation areas for preserving the different types of ecosystems. In this case it has demonstrated the inadequacy of the current reserve system and the need for many more. The distribution of a species of animal or plant is often a good indicator of a particular type of habitat and an adequate conservation programme will try to include all potential types of habitat available in a given region. Frequently reserves have been confined to areas of little use for either things and so do not adequately sample the whole ecosystem. The availability of more and more physical data which can be combined with biogeographic data has greatly enhanced the potential contribution of the discipline for conservation. Geographical Information Systems have also been important for gap analysis. For example, Fearnside & Ferraz (1995) applied it to the vegetation of the Brazilian Amazon. It is not just centres of diversity and endemism that need to be preserved. Contact zones between species (e.g. Haffer, 1969, 1974) are of particular interest since they are often areas of genetic diversity and of active evolution. The identification of these areas is an important task for biogeographers. For the purposes of conservation, biography on the microscale can be just as important as biogeography on the macroscale of species distribution. An increasing amount of vegetation plot data is becoming available in the tropics. The local demography of species in these plots furnishes most useful data both for conservation and for the use of a species. The distribution of species in tropical rainforest is very uneven and in any individual plot many species have a very sparse distribution whereas a few may be clustered and more abundant. Information about this local demography is essential for adequate reserve design. If we do have data of use for conservation of the types mentioned above are we getting it out to those who need it and how do we transmit it? No politician will read a biological monograph or even this journal. However, they might watch a demonstration of biogeographic data using GIS on a screen. In fact a few have done just that at the Royal Botanic Gardens, Kew. I have deliberately worked on the biogeography and the biology of some of the well-known plants of the Amazon region such as the Brazil nut (Bertholletia excelsa) and the royal water lily (Victoria amazonica) that are known by most people. As a consequence it is possible to reach a much wider audience with data that give the reasons for conservation. The governor of Amazonas state Brazil and other leading politicians were quite interested to sit through a lecture I gave based on information about the familiar plants. There are many other ways to influence the world with our data such as through the internet and through the school curriculum. Geography has recently gained some ascendance in the National Curriculum in the UK. Can we ensure that this includes some biogeography as well? It is time that the design of reserves for the conservation of species and natural habitats was determined by scientific considerations rather than by such factors as low economic value of an area or its unsuitable topography for development. Biogeography has much to contribute to both the location of reserves and to reserve design. So far it seems that only island biogeography has been adequately applied to the problem yet the discipline can still contribute much more.