Researchers from the University of Rhode Island are contributing to an international effort to document life on Indonesia’s remote tropical seamounts — underwater mountains rising from the ocean floor that can host diverse deep-sea communities.
The expedition is generating some of the first systematic biodiversity data from tropical seamount ecosystems in the region and producing foundational baseline data on what lives on these features and how communities vary across depth and habitat.
The work is part of a collaborative project developed by researchers from Indonesian institutions and URI through a proposal selected under an open call organized by the Indonesian National Research and Innovation Agency (BRIN). The research team includes Drajad Seto, a postdoctoral researcher in URI’s College of the Environment and Life Sciences; URI Graduate School of Oceanography Associate Professor Roxanne Beinart; URI professor and Vice President for Research and Economic Development Bethany Jenkins and University Gadjah Mada faculty Noer Kasanah.
During the three-week OceanX-BRIN expedition from January 5–24, Seto served as the representative scientist for this research group on board the OceanX vessel, working alongside other scientists contributing to the broader expedition.
Filling a knowledge gap
Seamounts are often described as biodiversity “hotspots” because their topography can alter ocean circulation and enhance productivity. Organic matter produced near the surface can sink to support deep-sea communities far below.
Some seamounts host dense and diverse communities, while others appear comparatively sparse, and scientists still do not fully understand why. Factors such as depth, currents, habitat structure and food supply may all play a role.
In tropical regions like Indonesia, home to some of the world’s most extensive seamount chains, basic biodiversity data remains scarce. Through collaboration with Indonesian scientists and institutions, the international research team aims to help establish baseline biodiversity observations that future studies can build on.
Mapping seamount biodiversity
The team’s research examines how animal communities change from a seamount’s summit to its deeper slopes and whether those differences track with declining food availability. Working in coordination with a diverse team of Indonesian scientists, the researchers used a remotely operated vehicle (ROV) to collect biological samples across multiple depths.
To assess biodiversity, the team combined environmental DNA (eDNA) metabarcoding with traditional DNA barcoding of organisms collected during dives. The eDNA approach detects genetic traces that animals leave behind in the water, allowing researchers to identify species without directly observing them.
However, interpreting those signals depends on having reliable reference DNA sequences. By collecting organisms with the ROV and generating DNA barcodes for them, the researchers aim to expand the reference databases needed to identify species in future eDNA studies, an important step for studying biodiversity in the deep sea, where many species remain undocumented.
