Sunday, 9 March 2014

No Paper Heavens, Marine Protected Areas Examined

Conservation of marine biological diversity calls to foster protected sea-life from exploitation. Putting part of the seas under protection is a means to achieve that. In the last years the size and the the number of Marine Protected Areas increase rapidly. Currently about 2% of the world's seas are under full protection. The target is to protect 10% of territorial waters by 2020. Currently the degree of protection varies, e.g. hook-and-line fishing may be allowed, and some of the Marine Protected Areas qualify just as "paper parks".

Marine Protected Areas should generate socio-economic benefits to make their case. Some marine Protected Areas are known not to reach their full potential because of illegal harvesting, mis-regulation that allow detrimental harvesting, or mis-sizing so that animals leave the Marine Protected Areas when living their habitual life.

The World Database on Protected Areas (WDPA) [1]. 
Recently Graham Edgar and colleagues [*] examined the conservation benefits of 87 Marine Protected Areas worldwide. Their insight: benefits of Marine Protected Areas increase dramatically with the accumulation of five key properties: no take, well enforced, age, size, and isolation.

By its very nature, isolation is difficult in marine environments. Water and species move. Nevertheless the natural gradients of marine environments provide for guidance about natural confinements.

More than half of the Marine Protected Areas examined by Graham Edgar had only one or two key properties. These protected areas were ecologically indistinguishable from unprotected areas. They conclude: meeting only two of the five properties does not have much effect, but bundling four or five has effect.

Comparing effective Marine Protected Areas, which have four or five key features, with non-protected seas is indicating that total fish biomass is about three times higher. Also, effective Marine Protected Areas have twice as many large fish species, five times more large fish biomass, and fourteen times more shark biomass than fished areas.

Global conservation targets based on area alone will not effectively protect marine biodiversity. Design of Marine Protected Areas and their durable management needs five for conservation: no take, enforce, age, size, and as much isolation as possible. That is a difficult task but not mission impossible.

[1]  IUCN and UNEP-WCMC (Oct 2013). The World Database on Protected Areas (WDPA). Available

[*] Global conservation outcomes depend on marine protected areas with five key features; Graham J. Edgar, Rick D. Stuart-Smith, Trevor J. Willis, Stuart Kininmonth, Susan C. Baker, Stuart Banks, Neville S. Barrett, Mikel A. Becerro, Anthony T. F. Bernard, Just Berkhout, Colin D. Buxton, Stuart J. Campbell, Antonia T. Cooper, Marlene Davey, Sophie C. Edgar, Günter Försterra, David E. Galván, Alejo J. Irigoyen, David J. Kushner, Rodrigo Moura, P. Ed Parnell, Nick T. Shears, German Soler, Elisabeth M. A. Strain & Russell J. Thomson; Nature 506, 216–220 (13 February 2014)