Operationalising connectivity in the spatial management of mangroves

Mangroves form highly interconnected ecosystems, where natural rehabilitation often relies on propagule dispersal to recolonise degraded or fragmented areas where suitable hydrological and substrate conditions exist. Yet, dispersal and connectivity are rarely integrated in the spatial planning of mangroves due to limited data and a lack of operational guidance. To address this gap, we developed and tested a decision support framework that integrates mangrove connectivity and condition to guide spatial management prioritisation. Using the central Great Barrier Reef, Queensland (Australia) as a case study, we simulated dispersal of two mangrove species: Rhizophora stylosa and Bruguiera gymnorhiza, using a biophysical model driven by oceanographic currents (SLIM) and parameterised using experimentally derived propagule viability and floating duration data (IBM). Network analysis was applied to the dispersal outputs to identify mangrove sub-population importance (centrality) and key dispersal pathways that sustain connectivity processes. Habitat patches defined by five connectivity-driven management objectives were then mapped and assessed alongside satellite-derived mangrove condition (NDVI) to generate an urgency index for spatial management prioritisation. Our results identified critical areas of replenishment sources or connectivity corridors that overlapped with degraded mangrove habitats, highlighting these areas for targeted management. This framework demonstrates how explicitly incorporating connectivity into spatial planning can improve the identification of areas that may contribute to mangrove recovery and persistence under accelerating climate change and coastal development.