Climate, heatwaves, nearshore ecosystems and the sunflower sea star

Abstract

At the nexus of the ocean and the land lies the nearshore ecosystem, which includes the intertidal zone, an area exposed during low tides and submerged during high tides. Species in the intertidal are adapted to a high level of environmental variability including high temperatures, waves, and salinity variability. Species’ tolerance to desiccation in part determines the elevation within the intertidal zone they occupy. Biological interactions also determine the presence and abundance of species. Predators like sea stars and competition for space can influence numbers of barnacles and mussels. As ocean and air temperatures continue to rise with climate change and marine heatwave are becoming more common intertidal species may have limited space to move vertically in response to sea level rise and many species are already living at the edge of their physiological tolerances for high temperatures.