Temperate reefs from around the world are becoming tropicalised, as warm-water species shift their distribution towards the poles in response to warming. This is already causing profound shifts in dominant foundation species and associated ecological communities as canopy seaweeds such as kelp are replaced by coral species.
This study argues that the cascading consequences of tropicalisation for the ecosystem properties and functions of warming temperate reefs depend largely on the taxa that end up dominating the seafloor. The authors present three potential tropicalisation trajectories, that differ in whether seaweeds, turf or corals become dominant.
The study highlights potential gains to certain ecosystem functions for some tropicalisation endpoints. It is underlined that understanding these changes in flows of energy and materials is essential to formulate new conservation strategies and management approaches that minimise risks as well as capture potential opportunities.
The authors outline management practices that may either mitigate predicted structural and functional changes or make the most of potential new opportunities in tropicalised reefs. These include marine protected areas to increase resilience and connectivity, the development of new fisheries that target range-expanding invaders, and assisted evolution and migration strategies to facilitate the dominance of large habitat formers like corals or seaweeds.
Vergés et al. (2019) Tropicalisation of temperate reefs: implications for ecosystem functions and management actions. Functional Ecology 33:1000-1013.