"Modeling habitat connectivity for conservation. of semi-aquatic vertebrates is a particularly. challenging task, due to the fine-scale and linear. distribution of riverine habitats and to the capacity of. species to move both on freshwater and terrestrial. realms. We showed how the integrated analytical. framework provided by the habitat availability (reachability). metrics and their fractions can be used to. effectively evaluate the distinctive roles and contributions. of both habitat patches (aquatic and riparian) and. linkage areas (permeable land matrix) to the connectivity. and functioning of a complex system composed. of multiple river catchments. Analysis focused on the. Eurasian otter (Lutra lutra L.), one of the most. endangered mammals in Italy. We developed a. network connectivity model based on suitable otter. habitats and multiple least-cost paths between catchments.. A graph analytical approach was used to. identify critical nodes and links for the potential. expansion and long-term viability of the species in the. region. Our results showed that few basins concentrate. most of the importance for sustaining the overall habitat connectivity, due to the extension of suitable. habitats they contain, their strong connections with. other basins, and their importance as stepping stones. that uphold ecological fluxes between otherwise. weakly connected habitats. The potential contribution. of each basin to enhance the dispersal and expansion of. otters in the area strongly depended on the key. functional paths (sequences of links and nodes) among. the catchments. We identified vacant basins that could. be colonized by otters in the near future, and connecting. areas in the intermediate matrix that might be. preferentially used to conduct and promote dispersal. movements and gene flow in the area. The novel. approach here adopted could be easily extended to. other semiaquatic species and catchment systems,. offering a management strategy to preserve the. hydrographic network as an integrated system, as well. as a joint evaluation of the role of both the river courses. and the matrix in between in a single landscape model."
|Digital Object Identifier (DOI):||10.1007/s10980-011-9682-3|
|Codice identificativo ISI:||WOS:000300088700011|
|Codice identificativo Scopus:||2-s2.0-84856223582|
|Appare nelle tipologie:||1.1 Articolo in rivista|