Project: Collaborative Research: Cleaning stations as hubs for the maintenance and recovery of microbial diversity on coral reefs.

NSF Award Abstract:

Biodiversity in the ocean is influenced by interactions between disparate organisms which ultimately shape population, community, and ecosystem dynamics. Symbiotic interactions involving subsets of species can have disproportionate impacts on communities, reaching well beyond each interacting species. Coral reefs host some of the most iconic symbiotic interactions in nature and are host to the highest diversity of life on the planet. Cleaning symbiosis, wherein small fish or shrimp remove external parasites and associated microorganisms from specific clients, is common on coral reefs. Sites on the reef occupied by cleaners, or “cleaning stations”, attract a wide variety of fish species that engage in direct physical contact with the cleaner. These highly used territories are viewed both as “clinics of the sea”, where parasitized and sickly fish seek the service of cleaners, but also as potential “garbage dumps”, where unnecessary parasites and other microorganisms are removed. This project seeks to understand the role of cleaning symbiosis transferring microbes in coral reef environments. This research supports training for U.S. graduate students and for undergraduates from Arkansas State University, a primarily undergraduate institution that includes a large population of first-generation college students. These students participate in field site research and have opportunities to visit the Woods Hole Oceanographic Institution for broader exposure to ocean science and more specific laboratory training. The project strengthens international collaboration and further builds on the existing relationships between the team of scientists and resource managers, local divers, fishers, and boat operators, as well as K-12 schools and environmental education programs, and will therefore contribute to local economies. Outreach efforts include a film highlighting this research and publicly accessible narratives shared through press releases and an on-line magazine.

While the benefits of cleaning to reef ecosystem health have been extensively studied, the cleaning costs for cleaner species and the role of cleaning stations as potential sinks for microbial diversity and possibly even pathogens have never been assessed. Here, the researchers utilize the unique features of cleaning stations to understand transfer of bacterial and archaeal symbionts amongst fish and within coral reef environment. The study capitalizes on cleanerfish access to multiple variety of hosts or clients within stations to address new questions about how cleanerfish act as vectors to transfer microorganisms between hosts on a reef and if and how these microorganisms may play a broader functional role in reef resilience. Specifically, the project addresses the following hypotheses: 1) Cleanerfishes serve as keystone regulators of microbial communities, enhancing microbial community diversity and transferring key microbial species between clients, and 2) Cleanerfishes are a particularly important contributor to reef resilience, facilitating recovery of the microbiome following disturbance. The research team uses an integrative interdisciplinary approach involving field and laboratory observations and experiments, and molecular-based tools. The core research team includes experts in cleaning mutualisms, fish behavior, coral reef ecology, and microbial ecology. The proposed project aims to link behavior of individual organisms with ecosystem-level process.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.