Wastewater pollution is a persistent but understudied driver of coral reef degradation. Here, we investigate how reef fish assemblages respond to environmental gradients shaped by chronic wastewater exposure, combining trait-based analyses with long-term environmental data. We surveyed reef fish at seven sites along the leeward coast of San Andrés Island (Colombian Caribbean), quantifying variation in species richness, abundance, and eight functional traits. Environmental conditions were characterized using 13 years of water quality data, complemented by in situ measurements of benthic cover and algal nitrogen stable isotopes (δ15N). We calculated functional indices such as Functional Richness (FRic) and assessed trait–environment relationships. Impacted sites exhibited lower species richness and reduced FRic, driven by the absence of species occupying peripheral regions of functional space, including very mobile predators, demersal spawners, and small-bodied herbivores. Shifts in trait composition were explained by the combined influence of water quality variables and benthic composition (e.g. hard coral cover) along the pollution gradient. By demonstrating that wastewater exposure selectively erodes functional trait combinations underpinning key ecosystem processes, such as nutrient cycling, top–down control, and coral–fish mutualisms, this study highlights the importance of integrating functional metrics into reef monitoring and wastewater management strategies.
Plazas-Gómez R.A., Bejarano S., Magneville C., Prato-Valderrama J., Santos-Martínez A., Zwicker S. and Fujitani M. (2026) Reef fish functional trait responses to wastewater-driven environmental gradients. Marine Environmental Research 220: 108208. 10.1016/j.marenvres.2026.108208
@article{Plazas-Gómez2026,
Title = {Reef fish functional trait responses to wastewater-driven environmental gradients},
Author = {Plazas-Gómez, Ramón Alejandro and Bejarano, Sonia and Magneville, Camille and Prato-Valderrama, Julian and Santos-Martínez, Adriana and Zwicker, Sarah and Fujitani, Marie},
Journal = {Marine Environmental Research},
Year = {2026},
Pages = {108208},
Volume = {220},
Doi = {10.1016/j.marenvres.2026.108208},
Abstract = {Wastewater pollution is a persistent but understudied driver of coral reef degradation. Here, we investigate how reef fish assemblages respond to environmental gradients shaped by chronic wastewater exposure, combining trait-based analyses with long-term environmental data. We surveyed reef fish at seven sites along the leeward coast of San Andrés Island (Colombian Caribbean), quantifying variation in species richness, abundance, and eight functional traits. Environmental conditions were characterized using 13 years of water quality data, complemented by in situ measurements of benthic cover and algal nitrogen stable isotopes (δ15N). We calculated functional indices such as Functional Richness (FRic) and assessed trait–environment relationships. Impacted sites exhibited lower species richness and reduced FRic, driven by the absence of species occupying peripheral regions of functional space, including very mobile predators, demersal spawners, and small-bodied herbivores. Shifts in trait composition were explained by the combined influence of water quality variables and benthic composition (e.g. hard coral cover) along the pollution gradient. By demonstrating that wastewater exposure selectively erodes functional trait combinations underpinning key ecosystem processes, such as nutrient cycling, top–down control, and coral–fish mutualisms, this study highlights the importance of integrating functional metrics into reef monitoring and wastewater management strategies.},
}
TY - JOUR
AU - Plazas-Gómez, Ramón Alejandro
AU - Bejarano, Sonia
AU - Magneville, Camille
AU - Prato-Valderrama, Julian
AU - Santos-Martínez, Adriana
AU - Zwicker, Sarah
AU - Fujitani, Marie
TI - Reef fish functional trait responses to wastewater-driven environmental gradients
T2 - Marine Environmental Research
PY - 2026
SP - 108208
VL - 220
DO - 10.1016/j.marenvres.2026.108208
AB - Wastewater pollution is a persistent but understudied driver of coral reef degradation. Here, we investigate how reef fish assemblages respond to environmental gradients shaped by chronic wastewater exposure, combining trait-based analyses with long-term environmental data. We surveyed reef fish at seven sites along the leeward coast of San Andrés Island (Colombian Caribbean), quantifying variation in species richness, abundance, and eight functional traits. Environmental conditions were characterized using 13 years of water quality data, complemented by in situ measurements of benthic cover and algal nitrogen stable isotopes (δ15N). We calculated functional indices such as Functional Richness (FRic) and assessed trait–environment relationships. Impacted sites exhibited lower species richness and reduced FRic, driven by the absence of species occupying peripheral regions of functional space, including very mobile predators, demersal spawners, and small-bodied herbivores. Shifts in trait composition were explained by the combined influence of water quality variables and benthic composition (e.g. hard coral cover) along the pollution gradient. By demonstrating that wastewater exposure selectively erodes functional trait combinations underpinning key ecosystem processes, such as nutrient cycling, top–down control, and coral–fish mutualisms, this study highlights the importance of integrating functional metrics into reef monitoring and wastewater management strategies.
ER -
