Do Natura 2000 sites protect the most vulnerable species?

New research suggests that Natura 2000 sites are highly effective in minimising the number of endangered species of concern to European conservation. The findings may reduce concerns that poor coordination between Member States in setting up the European network of protected areas has led to inadequate protection of vulnerable species.

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Systematic reserve site selection in dynamic landscapes

Setting aside protected areas is widely recognized as one of the most effective measure to prevent species from extinction. The efficiency of networks of protected sites can be enhanced considerably by a systematic selection that considers the principle of complementarity (e.g. Margules and Pressey 2000). While the theory and practice of systematic reserve site selection has considerably advanced, changes in species composition, which is an important process in many ecosystems, especially in dynamic landscapes, is rarely considered. Usually, the data from several years are compiled. Site selection based on species occurrence data of a single year may result in remarkably divergent network configurations. Hence, temporal variability in species occurrences and composition should be routinely tested and considered in systematic reserve site selection in dynamic systems. For an implementation of conservation planning into praxis on a fine spatial scale in a fragmented landscape, this means, besides the collection of such temporal data (repeated surveys for more than 1 year), that species should be represented in a several sites so that recolonization from neighbouring sites is possible. Ideally, aggregated site networks that contain viable metapopulations should be considered as planning units. If the temporal variability is mainly due to low detection probability, sampling must be increased to obtain data suitable for systematic reserve site selection.

To assess the influence of temporal variability in species composition on the establishment of a reserve network in dynamic landscapes, Felinks et al. (2010) compared network configurations based on species data of small mammals and frogs sampled during two consecutive years in a fragmented Atlantic Forest landscape in south-eastern Brazil. Site selection with simulated annealing was carried out with the datasets of each single year and after merging the datasets of both years. Remarkable differences are reflected in both the identity of the selected fragments and in the amount of flexibility and irreplaceability in network configuration. Networks selected when data for both years were merged did not include all sites that were irreplaceable in one of the 2 years. Results of species number estimation revealed that significant changes in the composition of the species community occurred. Hence, temporal variability of community composition should be routinely tested and considered in systematic reserve site selection in dynamic landscapes.  

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