Christopher Costello, Steven D. Gaines, and John Lynham find that fisheries with individual fisherman's quotas are less susceptible to overfishing: Privatization prevents collapse of fish stocks, global analysis shows. The actual title of the article in Science is "Can Catch Shares Prevent Fisheries Collapse?" I haven't found a link to the original article or an earlier working paper yet.
The "privatization" here is the assignment to a right to a share in the seasonal or annual harvest. A fisherman with an individual and transferable quota has an asset whose value depends on the long-term health of the fish stock, and a greater incentive to care about that stock.
The abstract:
Recent reports suggest that most of the world’s commercial fisheries could collapse within decades. Although poor fisheries governance is often implicated, evaluation of solutions remains rare. Bioeconomic theory and case studies suggest that rights-based catch shares can provide individual incentives for sustainable harvest that is less prone to collapse. To test whether catch-share fishery reforms achieve these hypothetical benefits, we have compiled a global database of fisheries institutions and catch statistics in 11,135 fisheries from 1950 to 2003. Implementation of catch shares halts, and even reverses, the global trend toward widespread collapse. Institutional change has the potential for greatly altering the future of global fisheries.
And in conclusion:
Although bioeconomic theory suggests that assigning secure rights to fishermen may align incentives and lead to significantly enhanced biological and economic performance, evidence to date has been only case- or region-specific. By examining 11,135 global fisheries, we found a strong link: By 2003, the fraction of ITQ-managed fisheries that were collapsed was about half that of non-ITQ fisheries. This result probably underestimates ITQ benefits, because most ITQ fisheries are young.
The results of this analysis suggest that well designed catch shares may prevent fishery collapse across diverse taxa and ecosystems. Although the global rate of catch-share adoption has increased since 1970, the fraction of fisheries managed with catch shares is still small. We can estimate their potential impact ifwe project rightsbased management onto all of the world’s fisheries since 1970 (Fig. 2). The percent collapsed is reduced to just 9% by 2003; this fraction remains steady thereafter. This figure is a marked reversal of the previous projections.
Despite the dramatic impact catch shares have had on fishery collapse, these results should not be taken as a carte blanche endorsement. First, we have restricted attention to one class of catch shares (ITQs). Second, only by appropriately matching institutional reform with ecological, economic, and social characteristics can maximal benefits be achieved. Nevertheless, these findings suggest that as catch shares are increasingly implemented globally, fish stocks, and the profits from harvesting them, have the potential to recover substantially.
The Environmental Defense Fund reports here: Catch Shares Key to Reviving Fisheries. New Study Shows Innovative Approach Can Help Solve Overfishing. Here's Costello's website with background information on the study: Can Catch Shares Prevent Fisheries Collapse?
Revised Sept 19 to add a comment about how individual quotas give fishermen a greater interest in the long-term health of the fish stock.


