Marine Protected Areas (MPAs) are zones of different degree of protection from human intervention for the habitat and the species living in that space of the sea. They can have similar objectives as protected areas on land, though can be more difficult to enforce. Because technological advances in ships, fishing gear and positioning and fish locating equipment has been so dramatic, many previously natural reserves (e.g. in zones with heavy boulders on the sea floor, or near the border of polar ice) have become accessible to modern fishing vessels.

Heads of State and Government at the Johannesburg World Summit on Sustainable Development recognised that the ordinary technical measures, such as increasing mesh sizes to let baby fish slip through the nets, would not be enough in the face of massive overcapacity of the fishing fleets. In the Johannesburg Plan of Implementation (JPoI), among others, governments commit to

30(d) Encourage the application by 2010 of the ecosystem approach, noting the Reykjavik Declaration on Responsible Fisheries in the Marine Ecosystem and decision V/6 of the Conference of Parties to the Convention on Biological Diversity;

31(a) Maintain or restore stocks to levels that can produce the maximum sustainable yield with the aim of achieving these goals for depleted stocks on an urgent basis and where possible not later than 2015;

32(c) Develop and facilitate the use of diverse approaches and tools, including the ecosystem approach, the elimination of destructive fishing practices, the establishment of marine protected areas consistent with international law and based on scientific information, including representative networks by 2012 and time/area closures for the protection of nursery grounds and periods, proper coastal land use and watershed planning and the integration of marine and coastal areas management into key sectors

See the full text of Chapter 4 on natural resources of the JPoI here.

Some fishermen have heavily criticised and fought the establishment of marine protected areas as costly and ineffectual. Yet where ever fishing has been excluded or dramatically reduced in an area, the ecosystems recover and the abundance and size of species increases. Involuntary proof of the effectiveness is e.g. the coastal zone of Brunei Darussalam, where the government prohibits all fishing operations which exceed a one-day fishing trip. While the original objective may be to avoid interference with petroleum extraction, the positive effects on marine biodiversity and overall health on the marine ecosystems are great.

Yet many marine protected areas – still only about 3% of the oceans protected on paper - are not necessarily protected in practice. Indeed, a recent study concluded that even if more areas are declared protected, it is very difficult to enforce the rules effectively, so long as weak policing and massive fleet overcapacity make cheating attractive. This is sadly visible in several West African countries. However, efforts are underway to establish more effective community-based protected areas, such as in Joal, Senegal, with the help of WWF. The Parc National du Banc d'Arguin in Mauritania and other protected areas in the region, such as the Bijagos Islands in Guinea Bissau used to be supported by an international foundation, FIBA, to save unique wetlands and coastal habitats in West Africa. Some of its work has been taken on by the MAVA Foundation until 2022.

In California the debate is heated about the cost and effectiveness of a new MPAs. “... marine biologist Jennifer Caselle at the UCSB and her colleagues have put paid to this claim. (1)

Her team studied ten no-take and two fishing-restricted zones created in 2003 within the 100-kilometre-long Channel Islands National Marine Sanctuary off Santa Barbara. The scientists found that the number and size of the fish targeted for protection was greater in the reserve than outside. They also found that the ecosystem was healthier overall, with more predators such as spiny lobster and California sheephead helping to keep sea urchins under control. Because the urchins graze on kelp — an important habitat for many fish species — Caselle says that “the increased abundance of predators may help to prevent the transition of productive kelp forests into unproductive urchin barrens”  (2)

Fishermen are not always against MPAs. Where they have been involved pro-actively in the movements and see it as a protection for their future as well, rather than only as an exclusion mechanism where they loose out socially and economically e.g. to recreational tourism, they find much common ground with the conservation movement and such civil society organisations as WWF, which has long campaigned for marine biodiversity and MPAs in different countries.

If you want to dig a bit deeper and look at criteria where to place MPAs to make them most effective according to the objective pursued, have a look here.

If you want to learn more about existing MPAs, take a look at the world database by clicking here.

A major campaign to protect the Chagos Islands, while safeguarding the rights of the original inhabitants, achieved a big success with the declaration of a huge chunk of sea as an MPA as of 1 April 2010. Click here for the legacy. Learn from the success, keep the interest alive and help make sure the government designated area is enforced.

A brochure of the scientific criteria and guidance for MPAs and their networks in open ocean waters and deep sea habitats has been approved by the 9th Conference Of the Parties to the Convention on Biological Diversity (CBD) for the Azores, but is believed to have wider applicability. See the beautifully illustrated brochure here.

The CBD website has many resources in relation to protected areas, considered a cornerstone of species protection and rehabilitation. There is no shortage of guidelines, methodologies and experience accounts to learn from others and not reinvent the wheel. E-learning guides make 16 modules easily accessible if you want to understand better and direct your own efforts more effectively.

WWF calls it rightly a "smart investment into ocean health".

In a landmark decision on 24 December 2017, the UN has agreed to open negotiations for protecting the high seas. Most of fish catches in the high seas are realised by only 10 countries as fishing is most attractive in more productive waters on continental shelves and more nearshore. Phasing out high sea fishing would create a very large refuge where marine ecosystems could recover and "seed" adjacent areas for the benefit of all. Click here for more.

(1) Hamilton, S.L., J.E. Caselle, D.P. Malone and M.P. Carr, 2010. Proc.Natl.Acad.Sci. USA doi:10.1073/pnas.0908091107 (2010).

(2) citation from Dalton, R., 2010. Reserves 'win-win' for fish and fishermen. Nature, 463:1007.