A spatiotemporal analysis of coral reef regimes and fish herbivory across the Hawaiian Archipelago

Coral reefs can undergo shifts to alternative ecological regimes (or states) when exposed to stress. Acquiring a deeper understanding of when coral reefs become increasingly vulnerable to such shifts (i.e. regime shifts), and the stability of alternative regimes once unfolded, has important societal consequences as associated ecosystem services may change or be lost. Herbivory has been advocated as a key process that determines reef regimes. Here I show the co-occurrence of three distinct reef regimes across the Hawaiian archipelago from 2010-2015, providing empirical evidence for the existence of alternate regimes on a large spatiotemporal scale. I investigate the linkages between benthic regimes and the herbivory function, breaking down the taxonomic and functional diversity of the herbivore community through a trait-based functional space approach. This approach highlights a pattern of varying functional redundancy within herbivore communities across the regimes. A better understanding of these types of regime differences is integral for fully grasping where, when and how these shifts occur