Gaoping Submarine Canyon (GPSC) off the SW Taiwan connects to a small mountain river (SMR) originated at ~ 3000-m elevation.  The erodible lithology, heavy precipitations and steep topography of the SMR mean that the GPSC is prone to high sediment load and frequent turbidity currents.  The tectonic active margin also means that the GPSC is subjected to high risk of earthquakes, cascading the sediment mass wasting in the canyon.  More importantly, the GPSC is next to the world’s largest internal waves in the Luzon Strait.  The internal wave energy propagates into the GPSC and drives strong bottom intensified currents.

We demonstrated that the strong currents driven by the internal tides might erode the sediment and negatively affect the densities and diversity and alter the composition of benthic invertebrates.  The bottom shear might also re-suspend and prevent the organic-rich particles to settle and thus reduce the food supply to the benthos.  Despite the majority of submarine canyons are hotspots of benthic abundance, biomass, and diversity, the GPSC was apparently an anomaly due to strong currents and occasionally destructive sediment mass wasting. Our finding suggests that the GPSC may be a new paradigm in the study of submarine canyon ecology.