Award: OCE-1947735

Overarching Goal

The research goal of this project is to understand how larvae of endemic vent animals disperse effectively between vents; in particular, how they complete the journey by locating and settling in suitable habitat. This question has been one of the key unresolved puzzles in the ecology of deep-sea hydrothermal vents, since their discovery in the 1970s. The project also supported associated investigations of larval behavior and connectivity, providing new insights into the main study and revealing new areas of inquiry.

Scientific outcomes (Intellectual Merit)

Our outcomes include new discoveries in the following processes:

Larval settlement responses to microbial biofilms in field colonization experiments. Several hydrothermal vent species, including the foundation species Bythograea thermydron settled in higher abundance on surfaces coated with mature biofilms than on uncoated surfaces (Ladd et al. 2024). This result contributes to our understanding of how larvae can detect suitable habitat at deep-sea vents, allowing their communities to persist despite frequent catastrophic eruptive disturbances.

Larval behavioral responses to potential environmental cues. Using a newly developed High Pressure Plankton Observatory (HiPPO), we detected intriguing larval swimming behaviors in the presence of microbial biofilms in deep-sea conditions (Zúñiga Mouret et al. 2025). The discovery of a response to a potential cue informs the long-standing question of how vent larvae navigate their way back to suitable vent habitat after dispersing long distances in the water column.  

Large-scale changes over time in larval supply and connectivity. Our decades-long time-series of larval sampling at the 9-10°N vent field shows two distinct peaks in larval abundance; one associated with the eruption in 2006, and another immediately prior to the eruption in May 2025. We don’t know the mechanism(s) for these increases in abundance, but our observation motivates a new path of inquiry into possible influences of seafloor eruptions on larval production and supply in the deep sea.

Efficient larval transport in turbulence. In laboratory experiments on shallow-water gastropod larvae, we observed a remarkable behavior that allows gastropod larvae to ‘surf’ through turbulence by simply adjusting their orientation in response to the flow (DiBenedetto et al. 2025). This behavior allows them to move efficiently in turbulence, with little energy investment.

Broader Impacts

Relevance to ocean management. Our new information on larval settlement responses to environmental cues contributes to the understanding of how vent communities recover after natural eruptive disturbances. This basic research informs efforts to predict how resilient deep-sea communities may be to human disturbances, including deep-sea mining.

Workforce development. Our activities include training of undergraduate and graduate students in the field of oceanography in order to strengthen participation of under-resourced early-career researchers (including first-generation college students) in marine science. We provide training in experimental design, laboratory protocols, statistical analysis, data visualization, coding and data science, as well as professional development opportunities in ethics and career options, thereby contributing to innovative and resilient marine science workforce.

Instrument development. The design, workflow, and analytical approaches for the High-Pressure Plankton Observatory (HIPPO) are now published and accessible to a broad spectrum of users interested in behavior and physiology of plankton under deep-sea pressures.

Dissemination to communities of interest

Results of our research projects have been communicated via thirteen publications in peer-reviewed science journals, 7 data publications in the NSF BCO-DMO data repository,1 PhD thesis, and 1 Masters thesis. We presented results at twenty national and international science conferences, 2 national education conferences, and 1 international policy symposium.

 

Last Modified: 03/03/2026
Modified by: Lauren S Mullineaux