Fig. 4

Economic effects of implementing dive fees in marine areas with and without fully or highly protected marine protected areas (MPAs). (A) Total revenue generated from dive fees at different levels of fees charged per dive, with and without MPAs. The other panels show the corresponding (B) changes in dive industry revenue, (C) changes in consumer surplus, and (D) changes in the number of dives. The multiple lines per scenario represent the results of 500 model runs that consider randomly assigned dive numbers drawn from our estimated range of global dive numbers. The insets show the value difference between the MPA and no-MPA scenarios per model run. Note that in all model runs, the MPA scenario always generates greater dive fee revenue, dive revenue to the industry, consumer surplus, and change in the number of dives compared to the no-MPA scenario.