Meeting Abstract

2.1  Saturday, Jan. 4 08:00  Marine protected areas (MPAs) potentially reverse the development of fishing-induced traits in exploited populations of coral-reef fishes FIDLER, RY*; TURINGAN, RG; Florida Institute of Technology, Melbourne; Florida Institute of Technology, Melbourne rfidler2011@my.fit.edu

Size-selective fishing pressure causes directional shifts in body size toward the predominance of smaller and early maturing individuals in exploited fish populations. Small, early-maturing fish exhibit significantly reduced reproductive output, and therefore, reduced fitness. Although previous studies have shown significantly higher fish density and biomass within MPAs compared to adjacent fished reefs, the evolutionary implications of MPAs have been largely ignored in contemporary research. This study determined the variation in body-size frequency distribution, fish length, length-at-age, and Gonadosomatic Index (GSI) between MPAs and adjacent fished reefs to advance our understanding of the evolutionary implications of MPAs. Results revealed that: (1) about half of the MPAs surveyed had significant shifts in size-frequency distribution, skewed towards larger-bodied fishes compared to adjacent fished reefs; (2) the occurrence of significant shifts in size-frequency distribution was not affected by MPA age and size; (3) large-bodied fish were younger inside MPAs than same-size conspecifics in adjacent fished reefs; and (4) fish inside MPAs matured at an older age and larger body size than conspecifics in adjacent fished reefs. These results indicate that by eliminating fishing pressure within their boundaries, MPAs may ameliorate the adverse evolutionary effects of fishing on exploited fish populations.