Persistence of tropical herbivores in temperate reefs constrain kelp resilience to cryptic habitats

1. Global warming is facilitating the range-expansion of tropical herbivores, causing a tropicalization of temperate marine ecosystems, where tropical herbivores can suppress habitat-forming macrophytes, supporting the resilience of canopy-free ecosystem states. However, currently we lack a thorough understanding of the mechanisms that, on one hand, support the persistence of tropical herbivores and on the other support the recovery of temperate foundation species in tropicalized ecosystems, a required knowledge to predict potential regime-shifts and reversals to the baseline state of the ecosystem. 2. This study tested processes behind the persistence of the tropicalization of temperate reefs which experienced a complete loss of their kelp forests and an influx of tropical herbivores following a marine heatwave in 2011. For this, we assessed the feedback mechanisms that maintain turf-dominated states (recruitment of tropical herbivores, browsing and grazing rates and turf cover) and th...