Fisheries management impacts on target species status / by Francisco Blaha

Never shy of putting their views across, Ray Hillborn and a group of his colleges published recently a paper “Fisheries management impacts on target species status” on the PNAS Journal, that as usual has polarised some of the also well-known scientists at other ends of the fisheries discussion. Yet for me, the key finding (in bold italics below) is what we informally knew were the keys, but now is been scientifically proven are the keys, and I like that.

Summarized survey answers by dimension and country.

Summarized survey answers by dimension and country.

I will (as usual) quote some of the elements in the paper I find significant, yet I encourage you to read the original and see what the others are saying (the easiest place to do that is at his tweeter handle)

Interestingly the paper has a section I have not seen in many others:

There is broad public interest in the health of our oceans and marine life at local, national, and international levels. In recent years there has been increasing concern about whether our fisheries can sustainably provide seafood without overfishing fish stocks.

Several papers have described the global status of fish populations (i.e., their abundance and exploitation rates) and have hypothesized influences of fisheries management, but this report is unique in being a comprehensive analysis of how specific management attributes (which are numerous and operate simultaneously) affect population status across oceans, countries, and taxonomic groups.

Our report integrates management policies and population ecology to assess sustainable harvesting outcomes of target species in marine fisheries; results have important global food security implications.

Fisheries management systems around the world are highly diverse in their design, operation, and effectiveness at meeting objectives. A variety of management institutions, strategies, and tactics are used across disparate regions, fishing fleets, and taxonomic groups.

At a global level, it is unclear which particular management attributes have greatest influence on the status of fished populations, and also unclear which external factors affect the overall success of fisheries management systems. We used expert surveys to characterise the management systems by species of 28 major fishing nations and examined influences of economic, geographic, and fishery-related factors.

A Fisheries Management Index, which integrated research, management, enforcement, and socioeconomic attributes, showed wide variation among countries and was strongly affected by per capita gross domestic product (positively) and capacity-enhancing subsidies (negatively).

Among 13 management attributes considered, three were particularly influential in whether stock size and fishing mortality are currently in or trending toward desirable states: extensiveness of stock assessments, strength of fishing pressure limits, and comprehensiveness of enforcement programs. (surprise surprise!)

These results support arguments that the key to successful fisheries management is the implementation and enforcement of science-based catch or effort limits, and that monetary investment into fisheries can help achieve management objectives if used to limit fishing pressure rather than enhance fishing capacity.

Countries with currently less-effective management systems have the greatest potential for improving long-term stock status outcomes and should be the focus of efforts to improve fisheries management globally.