Based on a global survey, a group of researchers has found that the most effective fisheries management relies on science-based catch and fishing limits.

Summarized survey responses. Countries sorted by fisheries management index.
For a recent study in the Proceedings of the National Academy of Sciences, the researchers surveyed fisheries experts of varying backgrounds in the 28 countries that account for more than 80 percent of global catches. They collected information on research, management, enforcement, fishery status, fishing pressure, and socioeconomic data from 182 respondents. Then they created an index that reflects how well a country’s management systems are meeting their goals and how they affect fish trends in stock size, status, and fishing mortality.
The team found that of 13 characteristics of management systems evaluated, three emerged as the most influential: extensiveness of stock assessments, strength of fishing pressure limits, and the comprehensiveness of enforcement. Among the less influential characteristics were protecting habitat and collecting data on catch and body size.
The variables that most affected differences in country’s scores on the index were those that had to do with investment in management, with a country’s GDP having the greatest effect.
Of course, the silver lining for the countries with the lowest scores, say the researchers, is that they have the greatest potential for improvement.