Traditional Management of Fish Behavior to Increase Yield in the South Pacific

Periodically harvested closures (taboos) are widespread in parts of the Pacific and often temporary increases in yield are the goals of taboos, rather than improved ecosystem health. Local communities often implement taboos because fishing pressure has made target species more wary, making them harder to spearfish. We conducted a before-after control impact experiment in six areas: two taboo areas, two permanent closed areas, and two open fished areas in Vanuatu. We surveyed fish flight initiation distance (FID - how closely a spear-fisherman can approach a fish before it flees) and fisher catch for two target (Acanthuridae and Scaridae) and one non-target (Chaetodontidae) fish families in all six areas prior to and after opening of the taboos for three days of fishing. We found that FID was significantly lower in taboo and permanently closed areas compared to fished areas prior to the opening, for target families, and that only for the Acanthuridae did FID increase after opening. Catch per unit effort was higher for one periodically closed area than the fished site, but not for the other. These findings demonstrate that periodically closed areas can alter the behavior of coral reef fishes to achieve a short-term increase in fishing activity.