Mr Jeffrey Jolly1, Ms Erina Kawai1, Dr Chengze Li1, Mrs Yoko Shintani1, Mr Callum Hudson1, Ms Geminne Manzano2, Dr Fabian Goesser2, Dr Roger Huerlimann1, Professor James Reimer2, Professor Timothy Ravasi1,3
1Marine Climate Change Unit, Okinawa Institute of Science and Technology, Onna, Japan, 2Molecular Invertebrate Systematics and Ecology (MISE) Lab, Graduate School of Engineering and Science, University of the Ryukyus, Nishihara, Japan, 3Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, Australia
Biography:
Jeffrey Jolly is the lab manager for Timothy Ravasi's Marine Climate Change Unit. He comes from Pensacola, Florida, USA, where he completed his schooling and researched cell signaling pathways. He joined Daniel Rokhsar's lab in OIST in 2016, where he worked as the cephalopod operations manager. He joined Tim Ravasi's lab in 2020 as a lab manager.
Abstract:
Anchialine systems, or underground estuaries, are rare coastal ecosystems characterized by the mixing of groundwater and seawater, often hosting highly specialized and endemic species. In Okinawa, Japan, one of the world’s only two known “salt rivers” provides a unique opportunity to study interactions between hypogeal (underground) and epigeal (surface) components. This system features subterranean saltwater that mixes underground, is forced up through a spring, and flows 300 meters before emptying onto a fringing coral reef, creating distinct habitats. Open quarry mining activities in the vicinity might significantly threaten this ecosystem via sedimentation. We utilized eDNA metabarcoding and field surveys, sampling at the spring, middle river, mouth, and ocean, to characterize fish, invertebrates, and microbial communities within this Japanese natural monument. To assess the impacts of sedimentation and water quality degradation from heavy rain events, we measured turbidity, salinity, temperature, and dissolved oxygen and performed chemical analyses spatiotemporally. Metabarcoding results revealed distinct species distributions along the surface and underground components. We further observed a clear correlation between rain events and a decline in water quality. Our findings highlight the need for effective management strategies to protect these rare ecosystems from ongoing anthropogenic pressures.