A network approach to prioritize conservation efforts for migratory birds |
| |
Authors: | Yanjie Xu Yali Si John Takekawa Qiang Liu Herbert H. T. Prins Shenglai Yin Diann J. Prosser Peng Gong Willem F. de Boer |
| |
Affiliation: | 1. Ministry of Education Key Laboratory for Earth System Modelling and Department of Earth System Science, Tsinghua University, 30 Shuangqing Road, Beijing, 100084 China;2. Suisun Resource Conservation District, 2544 Grizzly Island Road, Suisun City, CA, 94585 U.S.A.;3. Network Architectures and Services Group, Delft University of Technology, Mekelweg 4, 2600 GA, Delft, the Netherlands;4. Resource Ecology Group, Wageningen University and Research, Droevendaalsesteeg 3a, 6708 PB Wageningen, the Netherlands;5. U.S. Geological Survey, Patuxent Wildlife Research Centre, Laurel, MD, 20708 U.S.A. |
| |
Abstract: | Habitat loss can trigger migration network collapse by isolating migratory bird breeding grounds from nonbreeding grounds. Theoretically, habitat loss can have vastly different impacts depending on the site's importance within the migratory corridor. However, migration-network connectivity and the impacts of site loss are not completely understood. We used GPS tracking data on 4 bird species in the Asian flyways to construct migration networks and proposed a framework for assessing network connectivity for migratory species. We used a node-removal process to identify stopover sites with the highest impact on connectivity. In general, migration networks with fewer stopover sites were more vulnerable to habitat loss. Node removal in order from the highest to lowest degree of habitat loss yielded an increase of network resistance similar to random removal. In contrast, resistance increased more rapidly when removing nodes in order from the highest to lowest betweenness value (quantified by the number of shortest paths passing through the specific node). We quantified the risk of migration network collapse and identified crucial sites by first selecting sites with large contributions to network connectivity and then identifying which of those sites were likely to be removed from the network (i.e., sites with habitat loss). Among these crucial sites, 42% were not designated as protected areas. Setting priorities for site protection should account for a site's position in the migration network, rather than only site-specific characteristics. Our framework for assessing migration-network connectivity enables site prioritization for conservation of migratory species. |
| |
Keywords: | bird migration connectivity conservation designation habitat loss network conectividad designación de conservación migración de aves pérdida de hábitat redes 鸟类迁徙 网络 保护设定 连通性 栖息地丧失 |
|
|