Ecological connectivity links estuarine and coastal marine habitats across seascapes via the movement of organisms and the action of physicochemical processes that also modulate the structure and function of ecosystems. As such, it plays an important role in the sustainability and resilience of estuarine and coastal marine environments affected by increasing anthropogenic climatic and non-climatic drivers of change. The health and functionality of these environments are coupled to ecological connectivity over variable spatial and temporal scales along the land-ocean continuum. The importance of ecological connectivity is manifested clearly at the land-sea interface in areas of high biotic productivity, biodiversity, and ecosystem services that provide goods and benefits to humankind. Ecological connectivity is a multifaceted process in these coastal ecosystems facilitated by the movement of biota (propagules, individuals, populations), nonliving materials (nutrients, organic matter, sediments), and energy from one location to another mediated by water flow, and it includes structural and functional linkages across seascapes which are vital for development of productive biotic communities and viable ecosystem service provisions. The disruption of estuarine and coastal marine environments by anthropogenic activities and pressures, as well as by extreme natural events such as hurricanes, tornadoes, earthquakes, and tsunamis, can significantly modify and fragment habitats, alter water circulation and biogeochemistry, impede the movement of organisms and nonliving materials, and reduce population abundance, persistence, and biodiversity as well as ecosystem services. In some cases, increasing anthropogenic activities and pressures, including those that escalate climate change effects, have severed ecological connectivity across extensive coastal seascape areas, decreasing trophic interactions and causing acute shifts in ecosystem structure and function. Multiple interactive anthropogenic and natural stressors cause the degradation and loss of habitats, alteration of ecological processes and biotic communities, and reduction of ecological connectivity and resilience, posing a threat to the sustainability of estuarine and coastal marine ecosystems. Assessing ecological connectivity in estuarine and coastal marine environments enables investigators to formulate frameworks for designing and achieving the conservation, restoration, and management goals necessary to improve ecosystem conditions. Restoring and maintaining ecological connectivity across seascapes
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