Increasing instability of a rocky intertidal meta-ecosystem

Significance As climate change increasingly stresses Earth’s biosphere, assessment of biotic responses is critical to human welfare. Although species-level changes have been researched for decades, studies focused at the multispecies level are infrequent, and those testing dynamical responses (species interactions, recovery from disturbance) even rarer. In the well-studied, iconic rocky intertidal ecosystem, annually repeated disturbance experiments in 2012–2019 revealed that the resilience of communities weakened (recovery rates slowed) and variability in recovery rates increased. These changes were associated with increased thermal stresses and shifts in upwelling currents, which can alter growth, decrease colonization rates, and kill organisms.