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Title: Relationships between a common Caribbean corallivorous snail and protected area status, coral cover, and predator abundance

As coral populations decline across the Caribbean, it is becoming increasingly important to understand the forces that inhibit coral survivorship and recovery. Predation by corallivores, such as the short coral snailCoralliophila abbreviata, are one such threat to coral health and recovery worldwide, but current understanding of the factors controlling corallivore populations, and therefore predation pressure on corals, remains limited. To examine the extent to which bottom-up forces (i.e., coral prey), top-down forces (i.e., predators), and marine protection relate toC. abbreviatadistributions, we surveyedC. abbreviataabundance, percent coral cover, and the abundance of potential snail predators across six protected and six unprotected reefs in the Florida Keys. We found thatC. abbreviataabundance was lower in protected areas where predator assemblages were also more diverse, and that across all sites snail abundance generally increased with coral cover.C. abbreviataabundance had strong, negative relationships with two gastropod predators—the Caribbean spiny lobster (Panulirus argus) and the grunt black margate (Anisotremus surinamensis), which may be exerting top-down pressure onC. abbreviatapopulations. Further, we found the size ofC. abbreviatawas also related to reef protection status, with largerC. abbreviataon average in protected areas, suggesting that gape-limited predators such asP. argusandA. surinamensismay alter size distributions by targeting small snails. Combined, these results more » provide preliminary evidence that marine protection in the Florida Keys may preserve critical trophic interactions that indirectly promote coral success via control of local populations of the common corallivorous snailC. abbreviata.

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Publication Date:
Journal Name:
Scientific Reports
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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