Stable and resilient kelp forests across a latitudinal gradient of thermal stress

Global environmental change is reducing ecosystems' capacity to resist and recover from disturbances, threatening ecological stability. Stability is multidimensional, encompassing resistance (initial impact), resilience (rate of recovery) and recovery (extent of return), yet these components are rarely quantified together. Kelp forests are among the world's most productive and biodiverse marine ecosystems but face increasing anthropogenic stressors, including ocean warming, overfishing and declining water quality, which may erode stability and drive phase shifts (e.g. to urchin barrens or algal turfs). We conducted a pulse‐disturbance experiment in shallow (3–5 m) subtidal kelp forests dominated by Laminaria hyperborea across four northeast Atlantic regions, with two sites nested in each. The study spanned ~9° of latitude and ~2.5°C in mean sea‐surface temperature. Following complete kelp removal in replicated large plots, disturbed areas were monitored for 6 years and compared with undisturbed reference areas. Based on known thermal tolerances, we predicted reduced resilience and recovery in warmer southern regions. Recovery followed a consistent trajectory across all regions, with high initial recruitment, rapid recovery of kelp density and canopy cover within 2 years and broader habitat structure and biomass returning within 5 to 6 years. Overall stability was high, but resilience differed regionally, with slower recovery in warmer southern regions, indicating increased vulnerability to future warming and disturbance. Synthesis . Laminaria hyperborea forests show high stability following pulse disturbance, but regional differences in resilience highlight the value of assessing multiple stability components. Future research should examine (i) resilience of associated communities, (ii) whether similar dynamics occur across the species' full range and (iii) interactions between physical disturbance and other environmental drivers. These findings advance understanding of ecological stability and provide guidance for managing and conserving ecologically and economically important kelp forest ecosystems.