The impact of Nassau grouper size and abundance on scuba diver site selection and MPA economics

Since many fisheries are size-selective, the establishment of marine protected areas (MPAs) is expected to increase both the average size and abundance of exploited species, such as the valuable but vulnerable Nassau grouper (Epinephelus striatus). Increases in mean size and/or abundance of protected species within MPAs may also provide nonextractive economic value to recreationalists. In this research, we assessed scuba diver preferences for viewing Nassau grouper and the marginal trade-offs that divers exhibited between fish size and abundance and between dive group size and price in the Turks and Caicos Islands. We used results from a paired comparison conjoint survey to develop market share simulations of dive site choice. Market shares increased significantly for sites with increased Nassau grouper abundance and mean size. This implies that Nassau groupers provide nonextractive economic value to divers. Our results suggest that accounting for the nonextractive value of increased fish abundance and size may influence the economic viability of MPAs.