Small predators dominate fish predation in coral reef communities

Area of Science:

• Marine biology
• Ecology
• Ichthyology

Background:

• Ecosystem processes are difficult to quantify at community levels, especially in complex environments like coral reefs.
• Predation is a key species interaction but is rarely quantified in aquatic systems.
• Existing fish-fish predation studies focus on larger size ranges, potentially missing significant ecological interactions.

Purpose of the Study:

• To model fish-on-fish predation within a hyperdiverse coral reef community.
• To assess the role of small fish in predation dynamics.
• To compare simulated predation events with observed data across functional groups.

Main Methods:

• Developed a model to simulate fish-on-fish predation.
• Analyzed body size data of predators and prey in coral reef ecosystems.
• Compared model outputs with existing meta-analyses and observational data.

Main Results:

• Predation events involving smaller body sizes (average predator 3.65 cm, prey 1.5 cm) are vastly underestimated in previous studies.
• Previously studied fish sizes represent only about 5% of likely predation events.
• Simulated predation patterns align with observed events when considering functional groups.

Conclusions:

• Coral reef fish predation is predominantly driven by small fish, often overlooked in ecological assessments.
• A paradigm shift is needed to incorporate small-bodied fish predation in understanding reef community structure.
• Quantifying predation by small fish is crucial for accurate ecological modeling and conservation efforts.