Marine protected areas (MPAs) are an important way to protect ecosystems from the effects of industrial activity. They can protect exploited species during critical stages of their lives, reduce secondary impacts of fishing, such as habitat degradation resulting from trawl fisheries, and act as "insurance" against poor management. By their simplest definition, marine protected areas are areas of ocean that are free from destructive forms of resource exploitation.
Not only can MPAs protect sedentary species such as shellfish, reef fish and rockfish, they can also help protect migratory species such as salmon and cod through the protection of key spawning and rearing grounds and migration corridors.
MPAs have been shown to increase the density of organisms within their boundaries, increase the average size of organisms, and increase the numbers of many exploited species. One benefit of MPAs is to return the protected ecosystem to its pre-exploited state, providing a baseline by which to judge the effectiveness of management in surrounding areas.
One of the greatest attractions of marine protected areas from a fisheries perspective is their ability to enhance fish populations outside of the reserve. Spillover into areas adjacent to MPAs can be expected to occur if the density and size of organisms increases within established reserves. Scientist from around the world are calling for more MPAs.
MPAs can also be important scientific tools, by providing information about the structure of unexploited ecosystems and how they compare to their exploited analogues. The management plans and objectives of MPAs can vary and can be tailored to the specific needs of the ecosystem being protected.
MPAs are not, however, a panacea for damaged marine ecosystems. An oil spill for example, is not impeded by the boundary of a marine reserve. Protection of habitat outside of reserves, regulations for industrial activity and reforms to fishing practices are essential complements to the establishment of marine protected areas.
Despite increasing evidence of the success of MPAs in maintaining and recovering marine ecosystems, less than one 10,000th of the world's ocean are is fully protected in MPAs, and Canada has protected less than 0.1 per cent of its ocean area. Some countries, however, have come further than most. The New Zealand parliament has announced its intent to protect 10 per cent of its coastline in MPAs before 2010; Australia has announced a plan to create the world's largest marine reserve; and the U.S. has been taking progressive steps to establish large marine protected areas. Canada is moving very slowly in comparison, as our report card on marine protected areas shows.
The successful establishment of MPAs that provide maximum benefit to the ecosystem requires in-depth science and a well-structured, transparent planning process based on the principles of ecosystem-based management.
While Canada has committed to establishing these planning processes under the mandate provided in the Oceans Act and Oceans Strategy, these processes are not well-developed and suffer from lack of funding. Visit the Fisheries and Oceans Canada website for more information on Canadian marine protected areas.