Some thoughts on the recent "Global conservation outcomes depend on MPAs with 5 key features" paper

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Dr Peter JS Jones, Dept of Geography, University College London (P.J.Jones [at]

See link for paper and for a conversation article by the lead author, Graham Edgar

To be clear from the outset, I think this is an excellent and very important paper that makes an outstanding contribution to debates about the need for effective MPAs. It represents a recent meta-analysis of the features that make MPAs effective in restoring fish populations, involving 87 MPAs in 40 countries. Interestingly, much of the data was collected by volunteer divers, representing a great example of the importance of ‘citizen science’.

It focuses on five key features of MPAs that promote the achievement of conservation outcomes:

  • no-take (i.e. no fishing activities at all)
  • well enforced (all users cooperate  or comply with the ban on fishing activities)
  • old (more than 10 years since no-take designation)
  • large (more than 100km2  in area)
  • isolated (surrounded by deep water or sand flats that isolate the MPA from similar fished habitats.

The analyses are focused on fin fish (including sharks), these being the targets of fishing as well as being reasonable proxies for the ‘health’ of the ecosystem of which they are components. These analyses do not directly assess the status of seabed habitats, the invertebrates that live on and in these habitats, and indeed often form such habitats (e.g. coral reefs and other biogenic reefs), or pelagic invertebrates, etc.

Encouragingly, the paper makes a major contribution to reports of the effectiveness of no-take MPAs in providing for the recovery and restoration of marine fish populations, provided they are relieved of all fishing pressures – we can rebuild them!

Less encouragingly, this paper reveals some very worrying trends:-

  • Only three of the 87 MPAs had all five features which promote the fulfilment of conservation objectives, and all of these were around islands isolated by deep ocean and remote from human settlements.
  • 90% (i.e. 78 out of 87) of the sample MPAs had three or less such features making them much less effective
  • 59% (i.e. 51 out of 87) of the MPAs were paper parks, the fish populations of which were indistinguishable from comparable fished areas outside of MPAs. This is probably an underestimate of the proportion of the world’s 10,000 MPAs that are paper parks, as the researchers are clear that their sample of 87 MPAs was biased towards MPAs that it was known had 4-5 of these features.
  • Large fish show an 80% reduction in biomass in fished areas all around the world, meaning that many large fish populations could be categorised as Critically Endangered under the IUCN’s Red List assessment criteria.

The paper also reports that some MPAs did less well than predicted in restoring fish populations due to “bias resulting from stakeholder consultation processes” related to decisions about where no-take MPAs were located, such processes presumably tending to steer no-take MPAs away from productive fish areas. This could support arguments for top-down MPAs that are designed on the basis of expert opinion.

 But is it too easy to conclude from this analysis that we should focus on large, no-take, isolated (particularly on remote islands), strictly enforced MPAs that are not compromised by stakeholder consultation processes?

Is there a risk that such analyses will undermine efforts for small no-take MPAs that are not isolated in that they are surrounded by areas that are exploited by humans from nearby populations and that are compromised in their design by stakeholder consultation processes?

The authors are keen to argue that this conclusion should not be reached as they are clearly aware of the related risks. They argue that MPAs that are not large but do have the other four features (no-take, well enforced, old and isolated) can deliver conservation benefits, coupled with large  MPAs elsewhere and improvements in broad-scale fisheries management practices (i.e. catch limits, effort controls, etc.). This does mean, though, that even the pursuit of marine areas that have four of these features will lead to a focus on remote, isolated areas, isolation being one of the four remaining features.

There is also a risk that funders, non-governmental organisations and agencies that can collaborate to pursue MPAs will be encouraged to seek sea areas that can comply with four (not large) or five features, leading to the neglect of even small MPAs in areas that are closer to human settlements and that raise challenges in promoting the cooperation and compliance of fishermen, i.e. a very significant proportion of the global marine area which supports high (but shrinking) levels of marine biodiversity. Even if areas with only three features are pursued (no-take, enforced, permanent), the paper infers, from a governance perspective, that stakeholder participation in the design of these could undermine their potential to be effective in terms of conservation outcomes.

These thoughts, questions and concerns aside, I must stress again that this is an excellent and outstandingly important analysis that focuses attention away from the pursuance of MPAs to meet notional targets, and encourages a much needed focus on ensuring that designated MPAs are more effective. It highlights the importance of “sufficient will among stakeholders, managers and politicians” for more MPAs that are no-take, that are complied with and that are large enough to extend into sedimentary seas beyond reef areas or into deeper water. This clearly points towards the challenges of effectively governing MPAs, an area I must declare an interest in as the author of the forthcoming book – Governing MPAs: resilience through diversity. This book resonates with this analysis, in highlighting the need for political will and for strong legal frameworks, in order to ensure cooperation and compliance with MPA restrictions.

At the end of the day, there is one thing that we must agree on, and that is the urgent need to reverse declines in marine fish populations. Effective MPAs coupled with improved fisheries management is clearly the way forward in this respect, and this paper will make major contribution to spreading awareness of the urgency of the need for effective MPAs.


I agree with Peter that this is an extremely important contribution, and one which should make all conservationists, MPA advocates, and planners take pause. But I take exception with the unstated assumption that the sole or primary reason for MPA establishment is protection of fish populations, and that how well an MPA does can or should be measured by recovery of populations of high trophic level fish alone. There are myriad other reasons why using spatial protections -- even strict protections such as no-take MPAs (a term which, by the way, pertains not only to prohibiting fishing but extractive activities of any sort) -- may be the best solution to a particular marine problem. MPAs can be designated to protect valued seascapes, protect highly productive habitats or benthic communities of organisms, reduce conflicts between user groups, launch demos for marine spatial planning, elicit better behavior in visitors (controlling trash, diver damage, etc.), create living laboratories for studying anthropogenic impacts and for raising awareness, and can even be used as a focal point for pushing regulations that reduce pollution and maintain water quality. To imply that an MPA that has achieved these goals but has not eradicated fishing is a failed MPA promotes a rather myopic view of what MPAs can achieve for conservation. The paper also neglects to discuss the unavoidable reality that the success or failure of future MPAs will in large part be decided by whether or not their designation occurs in the context of broader marine spatial planning. A huge, remote, old MPA may not need that, but as Peter rightly notes, most of the opportunities -- and I would argue, virtually all of the needs -- exist in places that are heavily used, and proximate to ever-growing pressures, including -- but not uniquely related to -- fishing.

Interesting tension between Edgar et al's paper (2014, arguing for large, isolated MPAs, isolation often meaning remote offshore, relatively unimpacted sea areas, even though they argue it does not necessarily mean this. So does remote often equate to residual, which Devillers et al (2014, criticise as biasing marine conservation away from impacted sea areas that are under pressure? Of course, we need BOTH types of MPA, i.e. NEOLI MPAs, which will tend to be in more remote, lightly-used, unimpacted sea areas and smaller MPAs in more metropolitan, intensely-used and impacted sea areas that will need to be pursued in more participative and opportunistic ways. It is not a question of whether NEOLI MPAs are the only 'real' MPAs or of whether focusing on NEOLI MPAs biases conservation towards residual seas and away from metropolitan, intensely-used and impacted sea areas where MPAs are 'really' needed. The fact that we need a DIVERSITY of types of MPA is the message the MPA comminity needs to get out there and work with, otherwise we may polarise arguments leading to a business-as-usual approach amongst decision-makers, as MPA scientists continue to engage in polarised arguments? Peter JS Jones, author of Governing MPAs - reslilience through diversity (

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