Identification and scenario-based optimization of ecological corridor networks for waterbirds in typical coastal wetlands

The limited space for coastal wetland conservation may conflict with achieving the 30 % protected area target under the Kunming-Montreal Global Biodiversity Framework. Identifying ecological corridors and enhancing connectivity in coastal wetlands is crucial for prioritizing critical areas. Our study presents a methodology for identifying ecological corridors for migratory waterbirds, using Yancheng coastal wetlands, a crucial stopover in the East Asian-Australasian Flyway, as a case study. We developed a novel framework for identifying and optimizing bird ecological corridors. Our approach integrates multiple key methodologies, including a comprehensive scoring system for selecting indicator species, an ecological source identification method combining MaxEnt and Morphological Spatial Pattern Analysis (MSPA), and a scenario-based simulation approach for optimizing corridor networks. We combined distribution data of 40 coastal waterbird species across four guilds with MaxEnt-simulated suitable habitat and MSPA-identified ecological source patches to improve source selection accuracy. Employing Circuit Theory, we identified critical ecological bottlenecks and facilitators. To optimize the ecological corridor network, we simulated three scenarios: (I) adding ecological stepping stones, (II) enhancing barrier points, and (III) simulating pinch point degradation. Scenario III proved most effective due to its lower optimization costs, robust planning, and high applicability, making it particularly effective in maintaining ecological network connectivity. Our scenario-based approach successfully enhanced connectivity and stability within coastal wetlands by targeting specific protection and habitat quality needs for diverse waterbird guilds. This methodology represents a significant step forward in migratory waterbird conservation in Yancheng and provides a valuable model for other globally significant biodiversity hotspots.