A six-year comparison across 28 Caribbean monitoring sites finds that reefs where juvenile fish were prioritised for protection in the first two years after a bleaching event show 2.4× the live coral cover of nearby sites that took adult-focused conservation approaches. The juvenile-first sites also showed faster recovery of structural complexity — the three-dimensional habitat that supports the rest of the reef food web.
The juveniles in question are grazing parrotfish and surgeonfish, which control the macroalgae that otherwise outcompetes recolonising coral larvae. Conventional protected-area design has historically prioritised spawning-age adults; the new data suggest that during a post-bleaching recovery window, the grazer demographic that keeps algae in check matters more than the demographic that reproduces.
The authors stop short of recommending a one-size policy; reef-system dynamics vary substantially between regions, and the Caribbean's macroalgae-dominated post-disturbance pattern may not apply to Indo-Pacific reefs with different algal communities.