Long‐term community dynamics are heterogeneous between fringing‐ and fore‐reef habitats on an Indo‐Pacific coral reef

Abstract Benthic community structure on present‐day coral reefs is often described as rapidly degrading, yet such summative statements do not capture the effects of spatial heterogeneity in communities. We focus on Moorea, French Polynesia, where the fore reef has shown high ecological resilience in recent decades, and ask whether the adjacent fringing reefs show different dynamics as a result of local environmental conditions. Communities on fringing reefs (~4‐m depth) were quantified at six sites from 2005 to 2022, and their community dynamics were tested for association with environmental conditions. Unlike the fore reef, most fringing reefs became degraded with respect to hard coral cover and showed low resilience, and their benthic communities differed more among sites than over time at any one site. The sites were each characterized by different temperature regimes, geomorphology, algal cover, and runoff of rainfall from the land. When pooled among sites and times, variation in coral community structure was most strongly associated with distance from the nearest reef pass and macroalgal cover, while benthic community structure was most strongly associated with the distance from the nearest reef pass and the area of building coverage (i.e., a development index). These findings underscore the strong effects of spatial structuring of anthropogenic disturbances, local‐scale spatial heterogeneity in reef communities, and the limitations of categorical descriptions of reef condition. Together with evidence of resilient fore‐reef communities around Moorea, these results reveal the potential for among‐habitat community asynchrony to mediate island‐scale coral reef community resilience and show that the community dynamics of fringing reefs are important components of holistic summaries of reef condition. While these fringing reefs exhibit degradation and varied resilience, these community trends were more strongly associated with local anthropogenic impacts than climate change. Modifications to local environmental management actions therefore have the potential to alter trajectories of coral community change at the same spatial scale.