title: Exposure of clownfish larvae to suspended sediment levels found on the Great Barrier Reef: Impacts on gill structure and microbiome.
abstract: Worldwide, increasing coastal development has played a major role in shaping coral reef species assemblages, but the mechanisms underpinning distribution patterns remain poorly understood. Recent research demonstrated delayed development in larval fishes exposed to suspended sediment, highlighting the need to further understand the interaction between suspended sediment as a stressor and energetically costly activities such as growth and development that are essential to support biological fitness. We examined the gill morphology and the gill microbiome in clownfish larvae (Amphiprion percula) exposed to suspended sediment concentrations (using Australian bentonite) commonly found on the inshore Great Barrier Reef. The gills of larvae exposed to 45 mg L(-1) of suspended sediment had excessive mucous discharge and growth of protective cell layers, resulting in a 56% thicker gill epithelium compared to fish from the control group. Further, we found a shift from 'healthy' to pathogenic bacterial communities on the gills, which could increase the disease susceptibility of larvae. The impact of suspended sediments on larval gills may represent an underlying mechanism behind the distribution patterns of fish assemblages. Our findings underscore the necessity for future coastal development to consider adverse effects of suspended sediments on fish recruitment, and consequently fish populations and ecosystem health.
authors.affiliation: 1] Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia [2] College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, 4811, Australia.
authors.forename: Sybille
authors.initials: S
authors.lastname: Hess
authors.affiliation: Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia.
authors.forename: Amelia S
authors.initials: AS
authors.lastname: Wenger
authors.affiliation: Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia.
authors.forename: Tracy D
authors.initials: TD
authors.lastname: Ainsworth
authors.affiliation: Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, 4811, Australia.
authors.forename: Jodie L
authors.initials: JL
authors.lastname: Rummer
mesh_terms: D000818:Animals; D057894:Coral Reefs; D005399:Fishes / Q000033:anatomy & histology / Q000382:microbiology; D019015:Geologic Sediments; D005880:Gills / Q000033:anatomy & histology / Q000382:microbiology; D007814:Larva; D064307:Microbiota