title: Resource partitioning along multiple niche axes drives functional diversity in parrotfishes on Caribbean coral reefs.
abstract: The recent loss of key consumers to exploitation and habitat degradation has significantly altered community dynamics and ecosystem function across many ecosystems worldwide. Predicting the impacts of consumer losses requires knowing the level of functional diversity that exists within a consumer assemblage. In this study, we document functional diversity among nine species of parrotfishes on Caribbean coral reefs. Parrotfishes are key herbivores that facilitate the maintenance and recovery of coral-dominated reefs by controlling algae and provisioning space for the recruitment of corals. We observed large functional differences among two genera of parrotfishes that were driven by differences in diet. Fishes in the genus Scarus targeted filamentous algal turf assemblages, crustose coralline algae, and endolithic algae and avoided macroalgae, while fishes in the genus Sparisoma preferentially targeted macroalgae. However, species with similar diets were dissimilar in other attributes, including the habitats they frequented, the types of substrate they fed from, and the spatial scale at which they foraged. These differences indicate that species that appear to be functionally redundant when looking at diet alone exhibit high levels of complementarity when we consider multiple functional traits. By identifying key functional differences among parrotfishes, we provide critical information needed to manage parrotfishes to enhance the resilience of coral-dominated reefs and reverse phase shifts on algal-dominated reefs throughout the wider Caribbean. Further, our study provides a framework for predicting the impacts of consumer losses in other species rich ecosystems.
authors.affiliation: Marine Sciences Program, Department of Biological Sciences, Florida International University, North Miami, FL, 33181, USA. adam@lifesci.ucsb.edu.|Marine Science Institute, University of California, Santa Barbara, CA, 93106, USA. adam@lifesci.ucsb.edu.
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Adam
authors.affiliation: Marine Sciences Program, Department of Biological Sciences, Florida International University, North Miami, FL, 33181, USA.
authors.forename: Megan
authors.initials: M
authors.lastname: Kelley
authors.affiliation: NOAA Fisheries, Southeast Fisheries Science Center, Miami, FL, 33149, USA.|Biological Sciences Department, California Polytechnic State University, San Luis Obispo, CA, 93410, USA.
authors.forename: Benjamin I
authors.initials: BI
authors.lastname: Ruttenberg
authors.affiliation: Marine Sciences Program, Department of Biological Sciences, Florida International University, North Miami, FL, 33181, USA.
authors.forename: Deron E
authors.initials: DE
authors.lastname: Burkepile
mesh_terms: D000818:Animals; D037421:Anthozoa; D017691:Caribbean Region; D057894:Coral Reefs; D004032:Diet; D017753:Ecosystem; D060434:Herbivory; D010473:Perciformes / Q000502:physiology*; D012624:Seaweed
keywords: Biodiversity; Fishing; Functional group; Herbivory; Niche partitioning