Artificial habitats host elevated densities of large reef-associated predators

Area of Science:

• Marine ecology
• Fisheries science
• Conservation biology

Background:

• Large predators are ecologically vital but face significant threats.
• Artificial reefs are used for habitat restoration, but their impact on large predators is unclear.

Purpose of the Study:

• To investigate whether artificial reefs benefit large reef-associated predators.
• To determine factors influencing predator abundance on artificial reefs.

Main Methods:

• Comparative field surveys of 30 artificial and natural reefs along the North Carolina coast.
• Analysis of predator densities (transient vs. resident) in relation to reef type and morphology.
• Global literature review on high trophic level fishes in artificial and natural habitats.

Main Results:

• Artificial reefs supported higher densities of large reef-associated predators than natural reefs.
• Higher densities were driven by transient predators, not resident species.
• Shipwrecks and reefs with greater vertical extent showed significantly higher transient predator densities.

Conclusions:

• Artificial habitats, particularly complex structures like shipwrecks, can effectively support large marine predators.
• Habitat complexity, specifically vertical structure, is a key factor in attracting transient predators.
• Artificial reefs may serve as valuable tools for enhancing populations of imperiled large predators.