Aggregating behaviour in invasive Caribbean lionfish is driven by habitat complexity

Area of Science:

• Marine Biology
• Invasive Species Ecology
• Fisheries Management

Background:

• Caribbean lionfish (Pterois spp.) are a highly impactful invasive marine vertebrate.
• Current management strategies, primarily recreational SCUBA diver culling, are inadequate.
• Understanding lionfish aggregation behavior is crucial for improving management efficiency.

Purpose of the Study:

• To investigate the drivers of Caribbean lionfish aggregation behavior.
• To determine if conspecific attraction influences aggregation.
• To identify habitat preferences associated with aggregation.

Main Methods:

• In situ observations of lionfish aggregations.
• Laboratory experiments testing visual and olfactory conspecific attraction.
• 3D habitat complexity modeling and analysis of lionfish morphology and life history.

Main Results:

• Aggregations were frequently observed in natural environments.
• No evidence of attraction to visual or olfactory conspecific cues was found.
• Lionfish prefer broad-scale habitat complexity and avoid fine-scale complexity, suggesting aggregations are coincidental.

Conclusions:

• Lionfish aggregations are likely driven by habitat structure that maximizes hunting efficiency, not social interactions.
• This finding can inform the development of artificial aggregation devices.
• Artificial devices could concentrate lionfish, thereby improving culling efficiency and management outcomes.