Abstract
Sea level rise (SLR) poses a significant threat to coastal ecosystems worldwide. Migratory shorebirds rely heavily on nearshore and intertidal ecosystems throughout the annual cycle and are currently undergoing global declines due to the loss of coastal habitat, suggesting that these species may be highly susceptible to future SLR. However, the effects of SLR on shorebird habitat—and, by extension, populations—remain poorly understood. Herein, we conduct the first systematic review of SLR impacts on the world’s shorebirds. The effects of SLR across all stages of the annual cycle are expected to be predominantly negative, with 78% of habitat-level studies and 89% of population- and individual-level studies documenting overall negative impacts. Declines in suitable habitat with future SLR have been projected for several sites of international and hemispheric importance to shorebirds, and impacts on shorebird populations are generally more severe than would be projected through habitat loss alone. However, maintenance or expansion of nesting and foraging habitat appears possible in certain areas where inland movement of coastal wetlands is unimpeded by anthropogenic development. Despite an increased focus on the impacts of SLR on shorebirds over the past two decades, the number of studies remains relatively small ( n = 37), and considerable knowledge gaps remain during the migratory period and throughout the Global South. Our findings highlight the threat of SLR to the world’s shorebirds and underscore the urgency of research on feasible adaptation and mitigation options to avoid the loss of coastal wetlands and their associated biodiversity.