Effectiveness of protected area networks in representing freshwater biodiversity:: the case of a Mediterranean river basin (south-eastern Spain)

1. Biodiversity is probably at greater risk in freshwater systems than in other ecosystems. Although protected areas (PAS) play a vital role in the protection of biodiversity and are the mainstay of most conservation polices, the coverage of biodiversity by existing PA networks is often inadequate and few reserves are created that take into consideration freshwater biota. 2. In this paper an attempt is made to address the performance of protected areas in the context of freshwater biodiversity conservation using data records for water beetles in a Mediterranean river basin. 3. Although the present PAS in the study area cover a relatively high number of water beetle species, the distribution and extent of reserves is still inadequate or insufficient to protect freshwater biodiversity, especially species of conservation concern. 4. Alternative area-selection methods (hotspots and complementary) were more efficient than PAs for representing water beetles. Within these, complementarity was the most efficient approach, and was able to represent all species in a significantly lower area than the current PA network. On the other hand, the future Natura 2000 Network will result in a great increase in the total area of protected land as well as in the biodiversity represented. 5. Unfortunately, the occurrence of a species within a protected area is not a guarantee of long-term survival because the extent of PAS is often insufficient and disturbances occur outside park boundaries. Thus, whole-catchment management and natural-flow maintenance are indispensable strategies for freshwater biodiversity conservation. Copyright (c) 2006 John Wiley & Sons, Ltd.