Stability and resilience of the keystone species complex determined in a subtidal kelp forest in Peru (SE Pacific)

Uribe R.A.; Ortiz M.; Hermosillo-Núñez B.; Díaz J.; Perea Á. · Estuarine, Coastal and Shelf Science (2026) · DOI: 10.1016/j.ecss.2026.109963

Resumen

This study determined the ecological keystone species complex (KSC) and its eco-social extension (including Fisher and Demand) for the kelp forest dominated by Eisenia cokeri along north-central Peruvian coast. Eight components, including species and functional groups, constituted the KSC contributing only 15.1% of the total biomass of the system. Based on Routh-Hurwitz's criterion for local stability, the ecological KSC reached the highest magnitudes when the components Chirodactylus variegatus and Crabs are in self-negative feedback. Although a slight increase in the average magnitude of resilience was detected in the case that C. variegatus and Crabs are in self-negative feedback, a much higher percentage of stable transient states was achieved. In the case of the eco-social KSC, the highest average value of stability and resilience were estimated when the components Fisher, Demand, C. variegatus and Crabs exhibit self-negative feedback. Consequently, management plans should be designed to limit the dynamic of the fisher, demand and the fishery pressure on C. variegatus and crabs. Likewise, the trajectory of the starfish Luidia magellanica should be monitored, which emerged as the most sensitive independent of the complexity of the KSC. In short, the determination of ecological and eco-social KSC and the quantification of stability and resilience allows us to approach ecosystem-based fisheries management under a context of global climate change. Therefore, monitoring the temporal persistence of both KSCs in E. cokeri -dominated kelp forests could serve as a key conservation mechanism to maintain the structural and functional integrity of this coastal benthic ecosystem intervened by artisanal fisheries. Copyright