Marine reserves drive both taxonomic and functional change in coral reef invertebrate communities

Abstract

A leading argument for no-take marine protected area (marine reserve) establishment is their contribution to the conservation of biodiversity, but the impacts of reserves on ecosystem functioning have seldom been quantified. This is unusual given the value of services provided by ocean ecosystems to human well-being. While no single index can describe ecosystem function, a set of life-history attributes possessed by taxa can be used to infer differences in ecosystem function across space and time. In this study, we use biological trait analysis to determine whether the attributes of invertebrate taxa differ between inside of six no-take marine reserves and outside, in fished areas in the Central Philippines. Using permutational multivariate analyses, we found that the composition of traits and taxa were significantly different between reserve and non-reserve areas. Habitat use, morphology and mobility traits were the biggest contributors to dissimilarity, indicating that reserves can have community-wide effects that change the functional composition of invertebrate assemblages. Notably, traits associated with coral habitat use, bearing a shell, lacking mobility and filter feeding are the most important traits associated with differences in community structure between reserve and non-reserve areas. At the taxa composition level, small shrimps, three families of bivalve, two families of burrowing snails and brittle stars are the most important contributors to differences in taxonomic community composition. The addition of organismal attributes to traditional taxa composition approaches provides richer insight into how ecosystems respond to protection and has the potential to inform practitioners on conserving for ecosystem traits.