Prior posts have noted that marine reserves can play a key role in helping areas and species to recover from the destruction of over-fishing and abuse of habitat. A new study emphasizes the importance of appropriate placement of marine reserves in order to achieve the maximum benefit.
Many new reserves have been established in recent years, though the total is still less than 2% of waters claimed by various nations, well under the goal of 20-30% recommended as part of the so-called Durban Action Plan of 2003. Be that as it may, research indicates that more targeted reserves could achieve significant benefits.
A study of 564 small reserves in the Philippines showed that not all are effective. The lack of patrolling and monitoring resulted in many being of no real utility. Other studies indicate that setting aside areas that have been heavily fished results in major improvements for an area. Having reserves in zones where growth and development of young fish occurs also helps support the recovery of an area. In the Black Sea, a study found that setting aside just 20-30% of the most impacted area within a marine reserve could accomplish nearly all of the goals set.
Like the old saw about real estate, location location location is key to the effectiveness of marine reserves. Size alone is not as important.
Reports on this topic can be found at http://www.pnas.org/content/early/2010/01/14/0908057107.abstract and http://www.pnas.org/content/early/2010/02/16/0908503107.abstract.