Marine protected areas enhance coral reef functioning by promoting fish biodiversity

Abstract

Preserving biodiversity and ecosystem function in the Anthropocene is one of humanity's greatest challenges. Ecosystem‐based management and area closures are considered an effective way to maintain ecological processes, especially in marine systems. Although there is strong evidence that such measures positively affect community structure, their impact on the rate of key ecological processes remains unclear. Here, we provide evidence that marine protected areas enhance herbivory rates on coral reefs via direct and indirect pathways. Using meta‐analysis and a path‐analytical framework, we demonstrate that, on average, protected areas increase the species richness of herbivorous fishes, which, in turn, enhances browsing rates on macroalgae. However, in all three regions studied (the Atlantic, Indian, and Pacific Ocean), a small subset of the herbivore assemblage accounted for the majority of browsing. Our results therefore indicate that ecosystem functioning on coral reefs may respond positively to both area closures and the protection of key species.

Coral reef ecosystem functioning: eight core processes and the role of biodiversity

“…This pattern is also present when examined across the Indo‐Pacific (Topor et al . ). Incorporating diversity effects into these frequently used, standardized assessments of ecosystem functioning on reefs promises to deliver rich insights into the respective roles of identity and diversity on coral reefs.…”

Herbivorous fish rise as a destructive fishing practice falls in an Indonesian marine national park

“…A reasonable stakeholder expectation is that areas closed to fishing will sustain higher levels of fish biomass and ecosystem function (Topor et al 2019). The temporal trajectories of fish community structure metrics in certain no-take reserves have indeed diverged from those observed in nearby fished areas (Micheli et al 2004, Aburto-Oropeza et al 2011, Graham et al 2015.…”

“…, Topor et al. ). The extent to which different management regimes influence the trajectory of the functional structure of fish assemblages over time, thus reorganizing the make‐up of ecosystem functions, is less clear.…”

“…Developing environmentally conscious, economically sound, and socially just fisheries is therefore a major governmental goal, and zoning plans including no-take and open-access areas are commonly developed with substantial stakeholder input throughout the region (Lucas 2009, Campbell et al 2013, White et al 2014. Prohibiting fishing in certain areas of the ocean can restore trophic structures, overall taxonomic richness, biomass of exploited resources, and key ecosystem processes (Russ and Alcala 1998, Micheli et al 2004, Rasher et al 2013, Topor et al 2019). The extent to which different management regimes influence the trajectory of the functional structure of fish assemblages over time, thus reorganizing the make-up of ecosystem functions, is less clear.…”

Intestinal microbes: an axis of functional diversity among large marine consumers

“…Intense herbivory thus increases the recovery potential of corals following disturbance and is becoming increasingly important, given the growing frequency of disturbances to tropical reefs [9]. High rates of herbivory collectively stem from a diverse portfolio of species (especially parrotfishes, surgeonfishes and rabbitfishes) [10,11], because each species feeds on a distinct algal assemblage [12][13][14]. Consequently, the ability of any given alga to escape attack declines as herbivore species richness increases [13].…”