Incorporating reef fish avoidance behavior improves accuracy of species distribution models

Area of Science:

• Marine ecology
• Fisheries science
• Ecological modeling

Background:

• Species distribution models (SDMs) predict fish presence using habitat data.
• Reef fish exhibit avoidance behavior towards divers, influenced by spearfishing.
• This fish wariness can affect assemblage metrics used in SDMs.

Purpose of the Study:

• To assess if minimum approach distance (MAD) serves as a proxy for fish wariness.
• To determine if incorporating MAD improves SDM accuracy for spearfishing-targeted species.

Main Methods:

• Used diver-operated stereo-video systems for fish surveys in Hawaiian marine reserves.
• Recorded MAD for targeted reef fishes inside and outside reserves.
• Compared SDM accuracy with and without MAD as a predictor variable.

Main Results:

• MAD varied between sites but not management types, supporting its use as a wariness proxy.
• Including transect-level MAD significantly enhanced the accuracy of SDMs for targeted fish biomass.

Conclusions:

• Fish wariness, indicated by MAD, is a crucial factor influencing fish distribution.
• SDMs incorporating fish wariness provide more accurate predictions of targeted fish biomass.