Climate drivers of reef fish functional diversity in the Atlantic Ocean

Abstract

Species richness assessments have governed our understanding of global biodiversity patterns. As a result, we have constructed an incomplete view of the drivers and the implications of the geographic distribution of biodiversity. In light of this incomplete view and the continued declines of global biodiversity, trait-based approaches to quantify functional diversity indices are key to reveal how evolutionary and ecological processes, together with climatic changes, shape biodiversity patterns. As functional diversity metrics are directly associated with species' habitat use and interactions they are better predictors of ecosystem function and service levels compared to taxonomic diversity. Reef fish are considered key constituents of marine ecosystems given their participation on several functions and represent an important source of animal protein for humans. Fish are therefore excellent biologic models to investigate the variations in functional diversity under different environmental drivers. Focusing on the Atlantic Ocean, this project will aim to (i) determine what components of functional ß-diversity (e.g. nestedness and turnover) are most spatially heterogeneous at the Atlantic Ocean; (ii) quantify how the functional redundancy and vulnerability of fish assemblages vary along the latitudinal gradient; (iii) identify which species are most vulnerable to rising sea surface temperatures, as well as what species are most important for biomass production; and (iv) determine which ecological drivers (e.g. competitive exclusion, saturation niche theory, and environmental filters) explain the variation in fish functional diversity along the latitudinal gradient. To meet these aims this project will integrate four extensive datasets comprising fish species occurrence checklists, local fish abundances from underwater visual census data, species life-history and functional traits, as well as abiotic factors available for the Atlantic Ocean in Bio-Oracle. (AU)