Marine protected areas alter fish community trophic structure: a global analysis.

SOLER G; CAMPBELL S; GALVAN DE; BUXTON C; BARRET N; DAWSON T; BERNARD A; THOMSOM R; STUART-SMITH R; EDGAR G

Queensland

Encuentro; AMSA2013 Golden Jubilee Conference; 2013

AUSTRALIAN MARINE SCIENCES ASSOCIATION

The effects of protection from fishing on fish trophic structure were assessed on a global scale using a dataset covering 79 MPAs, obtained through the Reef Life Survey program (www.reeflifesurvey.com). The biomass of higher carnivores, benthic carnivores, planktivores and herbivores in both no take and restricted (certain fishing practices allowed) MPA zones were higher than in adjacent open access areas. Differences in trophic group biomass ranged from 29 to 135% higher in no take and restricted zones compared to nearby open access sites. Three of the four trophic groups also showed significantly greater biomass (from 52 to 101%) in restricted zones than in open access areas; the exception was benthic carnivores. The biomass of the four trophic groups was also compared amongst young ( 10 years). MPA age had a significant effect on three of the four trophic groups; the exception was the planktivores. The biomass for higher carnivores, benthic carnivores and herbivores in medium and old MPAs ranged from 40 to 152% greater than in young MPAs. Previous studies have identified changes in fish trophic structure following protection of single MPAs; this study supports the generality of such results, suggesting that MPAs generally have differential effects across trophic groups of fish which change with time since protection.