The science of sustainable seafood, explained

Are MPAs the Best way to Protect the Ocean?

Comment by Robert Kearney, University of Canberra

Response to the CFood call for comment on the proposed closure of the high seas to fishing and on the claim that set percentages (e.g. 30%) of all marine environments should be closed to all fishing is definitely required. However, the influence of both the social and scientific media to the putative benefits of indiscriminate fishing closures necessitates that the debate be broadened and given much greater prominence to the fundamental issues of how to best achieve effective marine conservation and efficient resource use and allocation. The current debate is inadequately informed by critical analyses of net costs and benefits. Discussion is biased by the assumption that closing areas to all fishing is the appropriate default strategy for effective marine conservation and fisheries management. Fishing closures are espoused to automatically result in effective protection, often full, or at least ‘strong’ protection, of marine environments.

The use of emotive one-liners and sensational headlines has exploded with modern social media, aided by a flailing journalism industry that is increasingly reliant on the number of clicks, not the individual or collective expertise of journalists or respondents or the quality of data underpinning assessments. Not surprisingly, politicians use the lack of critical assessment in the debate (a failure of governments) to manipulate the numbers to claim environmental responsibility.

Much more critical discussion is needed on the costs of not using the most efficient methods to manage the impacts of fishing and of not committing to more effective actions to protect marine ecosystems and biodiversity. The fishery science community, together with other suitably skeptical ecologists, need to critically review the strategic issues that relate to the basic concept of area management as a preferred conservation and resource allocation measure in marine environments. A good starting point for a review would be an analysis of the relative effectiveness and efficiency of fishing closures, both targeted and indiscriminate, for resource allocation and biodiversity conservation. This review must include evidence-based evaluation of both costs and benefits.

Of course fishing needs to be managed. But in developed countries, the most effective outcomes can usually be achieved under specific fisheries legislation that enables actions to be tailored to individual problems. In most cases this will include management of individual activities over at least the majority of the area of the cause of the problem.

In parallel to the review of fishing closures, a risk-assessment approach to the identification and management of all significant threats to marine ecosystems should also be pursued. Such an approach could be expected to guide priority-setting for management activities.

In considering the costs of fishing, description and evaluation of the direct threats that it can pose (if not properly managed) must be prioritized. This is particularly necessary for countries or regions that do not have effective traditional fisheries management. Consideration of how and where each threat needs to be managed and what the most appropriate, cost-effective management could then follow. Evaluation of the indirect and secondary costs of inappropriate management would be less straightforward, but no less important. Assessment of secondary costs must include consideration of the cost of misdirection and diminution of effective management of marine ecosystems that can result from exaggeration and/or misrepresentation of the level of protection actually provided by alternative actions, such as non-specific fishing closures.

Consideration of the benefits of fishing would obviously include the direct contributions to security, nutrition, health, lifestyles, employment, and local, regional and global food supply. However, the debate needs to be much broader and acknowledge more indirect benefits and costs, such as the impact on national, regional and global biodiversity from the production of the same quantity and nutritional value of food from alternative sources. The urgency of this aspect increases as the global population grows. The Australian experience has wider implications: Australia has documented more than one hundred extinctions of terrestrial animals and plants (predominantly as results of urban and industrial development and agriculture) but not a single marine species has been reported to have met the same fate. Extinction as a direct result of fishing is extremely rare, or even non-existent, anywhere!

It is now obvious in Australia that the effectiveness of our fisheries management by traditional techniques (predominantly effort and catch controls) far exceeds that of the management of other threats to marine ecosystems. Great improvement in Australia’s fisheries management outcomes in the last decade has been well documented, including by the confirmed elimination of all overfishing in Australia’s Commonwealth managed waters. These outcomes continue to improve. Yet in the same decade, our marine ecosystems continued to deteriorate. This is in spite of Australia’s relatively high and increasing number and area of MPAs with extensive fishing closures. A pertinent expression of these problems is provided in the Great Barrier Reef Marine Park (GBRMP): recent assessments confirm continued deterioration of that intensively researched and heavily managed marine ecosystem and project that further deterioration must be anticipated.

A relevant comment on the interpretation of the protection of the Reef in the Park was provided when the President and Vice-president of the USA independently visited Australia in the last two years: they both publicly criticised the Australian Government and the people of Australia for not adequately protecting the Reef. Then, on their return to the USA, they announced more open-ocean, relatively remote, and immense ‘marine protected areas’. The message they were promoting was that they would not repeat Australia’s mistakes with the GBR; they would protect the USA’s oceans. And yet the actions they introduced were little more than indiscriminant closures to all fishing and other obvious forms of extraction. The GBRMP has had 33% of its total area closed to all fishing and extraction and up to 100% closed to selected forms of fishing for over a decade, during which time the deterioration of the Reef has, unfortunately, reached new highs. During this same decade, fisheries production from the GBRMP fell by approximately a third; relatively the same proportion as that of total fishing closures. The primary threats to the Reef have recently been confirmed to be climate change, land-based run-off and inappropriate coastal development. The managers of the GBRMP have acknowledged that to achieve effective protection, a much greater range of threats to the Reef needs to be managed, and they are progressively trying to do so. The President and Vice-president’s minders did not seem to be sufficiently cognizant of the limitations of even an extensive network of fishing closures that are relatively well enforced in a designated ‘marine protected area’.

The fundamental utility of area closures for marine conservation must be questioned, not just because many of the threats to marine areas arise outside the area being proclaimed as protected. The high degree of biological interconnectivity provided by a continuous aquatic medium greatly diminishes the management relevance, and subsequent conservation value, of artificial boundaries in marine environments. In marine systems, injections from outside sources of foreign substances (pollutants), organisms (pests and pathogens) and impacts on physical or chemical parameters (e.g. temperature and pH) are collectively, and even individually, much greater threats than all but the most radical and uncontrolled forms of extraction. The impacts of injection are extremely difficult to constrain in marine environments. Controlling harmful injections is not accomplished by closing areas to extraction based on geographical demarcations. Furthermore, when extraction must be managed, most forms can be effectively and efficiently controlled by targeted management specific to each activity and area of concern. In most cases, both the effectiveness and efficiency of the targeted management will be compromised if action is constrained, or even inappropriately prioritised, by predetermined boundaries.


Robert Kearney is a professor emeritus at the University of Canberra. Read some of his writing here.

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2 Responses

  1. “climate change, land-based run-off and inappropriate coastal development” are major problems of that there is little doubt. Yet its interesting that the fishing lobby often says these are the main issues but does almost nothing to address them directly on any meaningful scale. In fact they avoid these issues or often contribute to them directly. In Kearneys own patch for example the fishers party directly proposed legislation allowing (and pushes repeatedly for) the farming sector to be able to clear land without permits. Something that will do nothing but greatly increase issues with land based run-off. Silence from the fishing world there though instead they, like us here, are battling marine reserves.

    When will Kearney take the fishing lobby and their political representatives to task for their inaction on these major threats? While all is quite on that front I can’t help but treat with scepticism the continued shrill calls on marine reserves.

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