1st Edition of Marine Protected Areas for Whales, Dolphins and Porpoises
MPAs: How big and what level of protection should they have?
To date, most MPAs have taken their lead from land-based protected areas (PAs) in terms of size, boundaries and management strategies. With few exceptions, MPAs tend to be of similar size to PAs. Yet the world ocean occupies nearly three times as much surface area as the land. Using this ratio as a guideline, MPAs ought to be at least three times the size of, or three times more numerous than, land-based parks. The Durban Accord and Action Plan from the V World Parks Congress in 2003 stated that approximately 12 per cent of the world’s land area has protected status compared to less than 1 per cent of the world ocean and adjacent seas. This ‘less than 1 per cent’ may indicate some progress since 1995 when Kelleher et al reported only 0.5 (half a) per cent for all MPA protection, but the sea still lags well behind the land.
The sea differs fundamentally from the land and requires new ways of thinking and new approaches for conservation. Compared with land, the ocean is not only a horizontal but also a vertical, three-dimensional world, with different biomes, and accompanying species and ecosystems, occurring at different layers of the water column to a depth of seven miles (10 km) in the deepest trenches. Vast streams of water funnel across oceans, on the surface and at depth, carrying nutrients, planktonic life, larval forms, as well as contaminants, in isolated tubes or great fans of water. Columns of water sometimes flow from the sea bed to the surface, or vice versa, shifting on a seasonal basis or in response to climatic fluctuations. Land is comparatively static, while the oceans are mobile, active environments.
In view of all this, how large should MPAs be and what level of protection should they have? The larger and better protected they are, the more they will help replenish marine species and restore ecosystems, say Callum Roberts and Julie Hawkins (2000), citing considerable evidence in their excellent Fully Protected Marine Reserves: A Guide. Yet there is demonstrated value even for the smaller MPAs, as long as they contain substantial portions which are highly protected core areas, rated IUCN Category I, also known as no-take reserves (Ballantine, 1995). Still, if MPAs are smaller, then it is important that there are many more of them, forming effective networks, and that the protection is much greater in each one. The problem with MPAs today is that few of them contain highly, or fully, protected core areas. The father of MPAs in New Zealand and a strong proponent of full protection, Bill Ballantine, says that we should aim for 10 per cent of the world ocean to be in fully protected MPAs. And, in a recent joint statement entitled ‘Troubled Waters: A Call to Action’, more than 1600 scientists and conservationists declared that we should aim for 20 per cent of the sea as fully protected MPAs by the year 2020. Other calls, mainly to address the worldwide collapse of commercial fisheries, have suggested between 20 and 50 per cent of the sea to be protected to enable over-exploited fish stocks to recover. But much depends on the degree of human impact (Roberts and Hawkins, 2000). Where human impact is low, 5 per cent may be enough; where it’s high, 30 per cent may not be enough. Roberts and Hawkins and many other experts feel that 20 per cent is a minimum average goal, with some areas and habitats needing less protection and others more. The consensus from MPA practitioners around the world at the V World Parks Congress was that at least 20–30 per cent of each marine and coastal habitat should be in highly protected IUCN Category I areas. Yet, according to Roberts and Hawkins (2000), only an estimated 0.0001 (one ten-thousandth, or 0.01 per cent) of the world ocean exists in fully protected marine reserves. Even if this rough estimate is off by a power of ten, those who would protect the world ocean, restore exploited habitats and replenish depleted species have an awesome task in front of them.
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