Parrotfish predation drives distinct microbial communities in reef-building corals

Area of Science:

• Marine Biology
• Microbiology
• Ecology

Background:

• Coral microbiomes are sensitive to stressors, leading to dysbiosis and mortality.
• Parrotfish predation is a potential mechanism disrupting coral microbial communities through bacterial transmission or enrichment.

Purpose of the Study:

• Investigate if parrotfish corallivory alters coral microbial assemblages.
• Identify pathways, such as direct transmission, contributing to these changes.

Main Methods:

• Mesocosm experiments with parrotfish (Chlorurus spilurus) and corals (Porites lobata).
• Field observations of bitten and unbitten corals.
• Bacterial community analysis using 16S rRNA sequencing.

Main Results:

• Parrotfish predation increased coral bacterial diversity (2-4x) and altered community composition within 48 hours.
• Predated corals showed increased abundance of beneficial and opportunistic bacteria, some found in parrotfish mouths.
• Field samples confirmed higher microbial richness and altered composition in bitten corals, with shared taxa between corals and parrotfish.

Conclusions:

• Parrotfish corallivory is a potential route for bacterial transmission, impacting coral microbiomes and health.
• Corallivory can enrich rare bacterial taxa, potentially contributing to coral dysbiosis.
• Understanding corallivory is crucial for predicting coral disease dynamics in degrading reef ecosystems.