Intellectual Merit. Ecological surprises are most likely to be manifest in diverse communities where many interactions remain uninvestigated. Coral reefs harbor much of the world's biodiversity, and recent studies by the investigators suggest that one overlooked, but potentially important, biological interaction involves vermetid gastropods. Vermetid gastropods are nonmobile, tube-building snails that feed via an extensive mucus net. Vermetids reduce coral growth by up to 80%, and coral survival by as much as 60%. Because effects vary among coral taxa, vermetids may substantially alter the structure of coral communities as well as the community of fishes and invertebrates that inhabit the coral reef.
The investigators will conduct a suite of experimental and observational studies that: 1) quantify the effects of four species of vermetids across coral species to assess if species effects and responses are concordant or idiosyncratic; 2) use meta-analysis to compare effects of vermetids relative to other coral stressors and determine the factors that influence variation in coral responses; 3) determine the role of coral commensals that inhabit the branching coral, Pocillopora, and evaluate how the development of the commensal assemblage modifies the deleterious effects of vermetids; 4) determine how vermetid mucus nets affect the local environment of corals and evaluate several hypotheses about proposed mechanisms; and 5) assess the long-term implications of vermetids on coral communities and the fishes and invertebrates that depend on the coral.
Broader impacts. This collaborative research program will facilitate a broader understanding of coral reef ecology and the factors that impinge on the health of these highly valued, but imperiled, ecosystems. The investigators will continue our involvement in the Plan de Gestion de l'Espace Maritime, a management plan and network of marine protected areas around the island of Moorea. For example, by incorporating studies of vermetids into the assessment of the Moorea MPA network the work also will provide knowledge about possible deleterious effects of MPAs mediated through the reduction in harvest of vermetids. Project personnel will interact with local Polynesian community groups (e.g., Te Pu 'Atiti'a) to benefit from their traditional knowledge and to inform them of the research program. One supported student will lead up an effort to link with area schools (to be designed in collaboration with participants in the 'Atiti'a group). Team members include researchers and students from three countries: USA, New Zealand, and France. Two US-based graduate students and approximately four undergraduate students will be involved each year, and will benefit from working with scientists from these countries as well as with local teachers and elders. Regular exchanges between participating academic institutions (e.g., interfacing with the "Ocean Bridges" program) will enhance the interdisciplinary research and cultural experiences. This research will be conducted at the Moorea Coral Reef LTER site and will contribute to process-oriented studies that complement sampling conducted by MCR-LTER, as well as research conducted at the nearby French laboratory, Le Centre de Recherches Insulaires et Observatoire de l'Environnement (CRIOBE).
