Natura 2000, the European network of protected areas made up of over 26,000 sites throughout the EU, provides the basic structure that could promote connectivity across the continent for numerous species with wide distributions. Although it effectively supports species in the present, an important question to ask is how well it will support them in the future, given that climate change and land use changes will likely shift the configuration and composition of habitats in and around the protected network. Will connectivity be preserved?
Using four widely distributed birds of prey as models (Griffon vulture [Gyps fulvus], Golden eagle [Aquila chrysaetos], Egyptian vulture [Neophron percnopterus], and Lesser spotted eagle [Aquila pomarina]), Mazaris and colleagues analyze the current connectivity of the network, and further projected climate and land use change to predict how connectivity might be altered. Their analysis included three steps: 1. predict species distribution models under current and future climate and land use scenarios, 2. develop network models of potential connectivity based on current and future species distributions using graph-theory approach, and 3. compare network topology metrics to see if changes in species distribution over time might alter the network’s connectivity. This ultimately resulted in maps of the network structures for current and future distributions of each species.
The conclusions from the study show that despite the future loss of habitat enclosed within the protected sites, the network area, structure and configuration should be able to maintain strong connectivity for the studied bird species. However, not all species will remain equally connected, so that the concept of an umbrella species would not work well for preserving connectivity. The complex structure of the network allowed for some sites to disappear due to climate and land use changes, but in such a way that connectivity could be retained using linkages between alternative sites. It appeared that land use change was more likely to have a negative effect than climate change, at least for the extent of Europe and the species that were studied. The authors recommend that conservation measures be taken to prevent further habitat loss, and that protected networks be designed to ensure flexibility in how sites function to maintain connectivity.
Mazaris, A. D., A. D. Papanikolaou, M. Barbet-Massin, A. S. Kallimanis, F. Jiguet, D. S. Schmeller, and J. D. Pantis. 2013. Evaluating the connectivity of a protected area’s network under the prism of global change: the efficiency of the European Natura 2000 network for four birds of prey. PLoS ONE 8(3): e59640. doi:10.1371/journal.pone.0059640[/fusion_builder_column][/fusion_builder_row][/fusion_builder_container]