Researchers at the University of Hawaii analyzed data from fishing zones near the Papahānaumokuākea Marine National Monument, a massive protected area near the state that has banned commercial activity for more than 15 years. While the marine protected area, or MPA, was mainly designated to protect local species that don’t move around much, like coral and lobsters, the data suggests the zone has also helped tuna rebound, effectively serving as a fish nursery.
Article source: https://www.huffpost.com/entry/hawaii-tuna-overfished-catch-rates_n_635228c7e4b08e0e608cd8b0