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Marine Conservation

Protect Planet Ocean is an initiative by IUCN with the collaboration with UNEP-WCMC
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What are networks of MPAs and reserves?


Vietnam Nha Trang MPA, Elizabeth De Santo of IUCN
Vietnam Nha Trang MPA
Elizabeth De Santo of IUCN

Depending upon the type of MPA, and the level of protection it receives (through restriction of human activities), it can yield a wide range of benefits, including:


- maintenance and recovery of ecological systems

- maintenance of genetic diversity

- providing areas which can act as scientific reference points

- acting as a buffer against overexploitation and/or natural phenomena such as El Nino, hurricanes, etc

- improving the likelihood and rate of recovery from stresses such as climate change

- providing a means for sustainable income for local communities, through tourism and recreation;

- improving the provision of ecosystem services such as nutrient cycling, coastal protection

- protecting areas of cultural and spiritual significance for future generations

- supporting and sustaining fisheries outside the MPA/reserve by the movement of species from inside to outside


Scientific findings and management experience clearly indicate that MPAs can be powerful tools to help manage, protect and sustain valuable marine resources and the people and economies that depend on them.


The most dramatic changes have generally been observed in marine reserves (the most strictly protected type of MPA). Dramatic increases in the abundance, diversity, biomass, and size of fishes, invertebrates, and seaweeds - particularly species that were previously heavily exploited - have been observed. See the Science of Marine Reseves for some case studies on the changes that have been documents.


Ocean currents, migratory species, larval dispersal, nutrient exchange and other processes connect the sea within MPAs and reserves to land and sea some distance away. As a consequence, they can be (and often are) affected by activities taking place outside their boundaries, such as agricultural run off from land, climate change, and pollution. MPAs and reserves are therefore most likely to be effective if developed as networks of oceanographically connected protected areas, and also when used in conjunction with other management measures, such as broader-scale coastal zone management programs, species recovery plans, and fishery management plans.


Scientific research shows that MPAs can protect and enhance fisheries. Because MPA protections apply throughout a discrete area, they are effective at protecting fish stocks at various life stages in which fish are dependent on specific habitat types or locations. For instances, MPAs that prohibit certain fishing gear types can be used to protect spawning aggregation sites or nursery areas, such as estuaries, that are particularly vulnerable to fishing. Marine reserves, a type of MPA in which extractive and habitat-damaging uses such as fishing are prohibited, may actually enhance fisheries. In the absence of fishing pressure inside reserves, fish are able to grow to maturity and to increase in overall abundance. This leads to increased reproductive potential inside reserves, and the subsequent increased production of eggs and larvae, which can be transported by currents of the reserves to replenish nearby fishing grounds.


Studies of the biological effects of marine reserves far exceed those done on the socioeconomic effects. Some of the positive social effects of marine reserves on the local communities include increased environmental awareness, environmental stewardship, and educational opportunities. Marine reserves can help generate alternative income for fishers or other community members. Reserves can provide direct or indirect jobs for them. It is important to include local ecological knowledge of the fishers into the management strategy of the reserve. Tourism can also provide new economic opportunities for fishers.


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