Introduction

Out of the four components of biodiversity (UNEP 1992, Art. 2, Par. 2), two of them, namely species diversity and ecosystem diversity, focus on the fauna and flora in ecosystems and implicitly stress the importance of non-domesticated organisms living in their natural habitats. The term wildlife is used to scientifically describe plant and, more commonly, animal species without any serious human influence on habitats or population numbers. According to the Red List of Threatened Species, 1 per cent of all described species and 41 per cent of the species evaluated worldwide are seriously threatened by extinction (IUCN 2004). The dramatic increase in the rates of extinction can be expected to lead to a loss of half of all existent birds and mammals within the next 2–5 centuries (Wilson 1992; Stork 1997).

Species extinction is closely linked to (economically motivated) human activities such as land conversion, hunting and tourism. Irrespective of its immediate causes, species extinction is most often due to habitat modification and fragmentation (Groombridge 1992; MEA 2005). Thus, measures to protect habitats or ecosystems constitute the core of wildlife (or ‘in situ’) conservation. The World Conservation Union (IUCN) developed a classification and certification scheme for protected area management, reaching from human exclusion (strict nature reserve; category Ia) to coexistence of conservation and recreation (national park; category II) and to sustainable use (managed resource protected area; category VI). Therefore, an ecosystem (or habitat) approach targets at protecting representative samples of ecosystems or habitat types through control of land use.