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Oysters,Crassostrea virginica, are economically and ecologically valuable but have severely declined, and restoration is needed. As with the restoration and aquaculture of many shellfish species, restored oyster reefs are often impeded by predation losses, reducing restoration success and restricting locations where restored reefs are viable. Like many organisms, shellfish can modify their morphology to reduce predation risk by detecting and responding to chemical signals emanating from predators and injured prey. Oysters grow heavier, stronger shells in response to predation risk cues, which improves their survival. We tested if using predator cues to trigger shell hardening in oysters could be performed over a scale suitable for oyster reef restoration and improve oyster survival long‐term. We constructed an intertidal oyster reef using oysters grown in a nursery for 4 weeks while exposed to either exudates from Blue crab (Callinectes sapidus) predators or grown in controls without predator cues. Oysters grown with predators were 65% harder than those grown in controls, and after 1 year in the field, had a 60% increase in survival. Predation losses on the restored reef were significant, and the benefit of predator induction for survival was highest at intermediate tidal elevations, presumably due to intermediate levels of predation and abiotic stress. Our results suggest that manipulating the morphology of cultivated or restored species can be an effective tool to improve survival in habitats where consumers impede restoration success.
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This content will become publicly available on December 1, 2026
Growth-predation risk tradeoffs constrain the local distribution of a thicket-forming Staghorn coral to marginal reef habitats
Abstract On tropical reefs, environmental conditions and biological interactions are fundamental drivers of the spatial distribution of corals, which in turn influences community attributes and ecosystem rate processes. Here we focus on a major habitat-providing species of coral, the thicket-forming staghornAcropora pulchra, in Moorea, French Polynesia, to explore environmental attributes that shape its local distribution. At the island scale,A. pulchradecreased in abundance with increasing distance from the shoreline and was inversely related to nitrogen enrichment. To investigate growth-predation risk tradeoffs, we quantified growth and corallivory rates across major abiotic (nutrients, sedimentation) and biotic (corallivorous fish biomass) gradients. At 20 sites divided between fringing reef and mid-lagoon habitats, we quantified colony growth of transplantedA. pulchrafragments (nubbins) that were either exposed or protected from predators after 83 days. Nubbins protected from corallivores grew more in the mid-lagoon than on the fringing reef, whereas mid-lagoon nubbins exposed to predators only achieved 30% of the growth of exposed fringing reef nubbins. These findings suggest that a growth-predation risk tradeoff exists forA. pulchra, with predation a major constraint on the local distribution ofA. pulchrathickets that hinders the ability of staghorn to proliferate further offshore from the fringing reef.
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- Award ID(s):
- 2224354
- PAR ID:
- 10689053
- Publisher / Repository:
- Scientific Reports
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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