Comeros, Mia; Curtis, Megan; Howard Choat, John; Hoey, Andrew

Establishing the catchment to sea connection: spatial and temporal patterns of terrestrial pollution sources and impacts to herbivorous fish

2021

ARC Centre of Excellence for Coral Reef Studies, James Cook University; American Samoa Community College; College of Science and Engineering, James Cook University

"Here, we investigated the effects of increased nutrients and sediment accumulation rates on demographic processes to provide a mechanistic understanding of the effects of declining water quality on parrotfish and surgeonfish assemblages in American Samoa. Our overall objective was to document process-based responses of populations and assemblages of parrotfishes and surgeonfishes to varying levels of land use, and hence nutrient concentrations and sedimentation rates. We used a multi-faceted approach to address our objective: 1) assessed the spatio-temporal variation of nutrients and suspended particulate matter (SPM) across six sites in American Samoa over a 12-month period and used exploratory path analysis to relate dissolved inorganic nutrients, land use, and natural and anthropogenic drivers to benthic assemblages on adjacent shallow reefs; 2) examined the patterns of recruit abundance of the major piscine herbivores, parrotfishes and surgeonfishes, in six nearshore fringing reefs across an environmental gradient in Tutuila, and investigated the mechanisms driving these densities; 3) quantified growth and feeding rates two of the most abundant parrotfish and surgeonfish species in nearshore reefs on Tutuila, Chlorurus spilurus and Ctenochaetus striatus, respectively; and, 4) assessed the impacts of terrestrial run-off on the adult population structure of parrotfishes and surgeonfishes. Importantly, we worked closely with project partners to develop a research agenda that facilitated inclusive and equitable partnerships through focused training and co-production of knowledge products."

coral reef, reef fish, parrotfish, surgeonfish, recruitment, nutrients, suspended particulate matter (SPM), benthic assemblages, American Samoa

NOS

OCM

FY2021; CRCP Project ID 31209; Project Title: FY18 - Domestic Coral Reef Conservation Grants; Principal Investigator: Liz Fairey; Grant NA18NOS4820114.

NA18NOS4820114