Global conservation additionality hindered by persisting fishing pressure in marine protected areas
4 affiliations
- 1CNRS, PSL-EPHE-UPVD, CRIOBE, Maison de l’Océan, 195 rue Saint-Jacques, 75005 Paris, France.
- 2Instituto do Mar, Universidade Federal de São Paulo, Rua Carvalho de Mendonça, 144, São Paulo, SP 11070-100, Brazil.
- 3School of Aquatic and Fishery Sciences, University of Washington, 1122 NE Boat St, Seattle, WA 98195, USA.
- 4National Center for Ecological Analysis and Synthesis, University of California, 1021 Anacapa St, Santa Barbara, CA 93101, USA.
Abstract
Marine protected areas (MPAs) are the cornerstone of global marine conservation strategies. Yet, their capacity to achieve conservation gains (i.e., conservation additionality) hinges on the decrease in human threats to biodiversity within their boundary, a feature rarely measured or reported. Here, we test a central but underexamined question in global conservation policy: Have MPA implementations actually reduced within-boundary fishing pressure, currently the main direct human threat to marine biodiversity? Using a stratified before-after-control-impact approach, we investigated 861 MPAs of varying levels of protection across all ocean basins, representing half of global MPA coverage, and found that most implementations were not followed by decreases in industrial fishing effort. Protection levels strongly predicted the direction and magnitude of relative changes in fishing effort after implementation. Only fully protected areas were associated with significant decreases in fishing effort within boundaries. Highly protected areas were only associated with lower rates of increase in fishing effort within compared to outside boundaries. Both fully and highly protected areas were implemented in areas experiencing initial low fishing effort, reducing the overall abatement in fishing effort achieved. Conversely, areas with higher initial fishing effort tended to be attributed to MPAs with low levels of protection, also limiting abatement. Larger MPAs were associated with greater decreases in fishing effort, while time since implementation had no significant effect. Complementing targets of protection coverage and protection levels with conservation additionality targets, such as pressure abatement, could shift incentives from quantity to effectiveness of interventions and ensure positive biodiversity conservation outcomes.
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BibTeX
@article{ohanna2026global,
title = {{Global conservation additionality hindered by persisting fishing pressure in marine protected areas}},
author = {Millenne Ohanna and Juliette Jacquemont and Joachim Claudet},
journal = {Science advances},
year = {2026},
month = oct,
doi = {10.1126/sciadv.aed6878},
url = {https://europepmc.org/article/PMC/PMC13665934},
note = {CC BY-NC},
}
RIS
TY - JOUR
TI - Global conservation additionality hindered by persisting fishing pressure in marine protected areas
AU - Millenne Ohanna
AU - Juliette Jacquemont
AU - Joachim Claudet
PY - 2026
DA - 2026/10/14
JO - Science advances
DO - 10.1126/sciadv.aed6878
UR - https://europepmc.org/article/PMC/PMC13665934
AB - Marine protected areas (MPAs) are the cornerstone of global marine conservation strategies. Yet, their capacity to achieve conservation gains (i.e., conservation additionality) hinges on the decrease in human threats to biodiversity within their boundary, a feature rarely measured or reported. Here, we test a central but underexamined question in global conservation policy: Have MPA implementations actually reduced within-boundary fishing pressure, currently the main direct human threat to marine biodiversity? Using a stratified before-after-control-impact approach, we investigated 861 MPAs of varying levels of protection across all ocean basins, representing half of global MPA coverage, and found that most implementations were not followed by decreases in industrial fishing effort. Protection levels strongly predicted the direction and magnitude of relative changes in fishing effort after implementation. Only fully protected areas were associated with significant decreases in fishing effort within boundaries. Highly protected areas were only associated with lower rates of increase in fishing effort within compared to outside boundaries. Both fully and highly protected areas were implemented in areas experiencing initial low fishing effort, reducing the overall abatement in fishing effort achieved. Conversely, areas with higher initial fishing effort tended to be attributed to MPAs with low levels of protection, also limiting abatement. Larger MPAs were associated with greater decreases in fishing effort, while time since implementation had no significant effect. Complementing targets of protection coverage and protection levels with conservation additionality targets, such as pressure abatement, could shift incentives from quantity to effectiveness of interventions and ensure positive biodiversity conservation outcomes.
SN - 2375-2548
ER -