According to a new article in Nature (Global conservation outcomes depend on marine protected areas with five key features) most marine protected areas (MPAs) aren’t doing their jobs to project fish and other aquatic life.
The study found that 59 percent of MPAs looked at by researchers were “not ecologically distinguishable from fished sites.” MPAs are set up to protect marine life and habitat but operate under vastly different rules and regulations from region to region and most allow some level of fishing.
“MPAs often fail to reach their full potential as a consequence of factors such as illegal harvesting, regulations that legally allow detrimental harvesting, or emigration of animals outside boundaries because of continuous habitat or inadequate size of reserve.” For the 87 MPAs investigated worldwide, the conservation benefits increased exponentially with the accumulation of five key features: i) no take, ii) well enforced, iii) old (>10 years), iv) large (>100 km2) and v) isolated by deep water or sand.
The researchers found that effective MPAs display at least four out of the five key features. Where effective MPAs showed to have twice as many large (>250 mm total length) fish species per transect, five times more large fish biomass, and fourteen times more shark biomass than fished areas. Sadly, 59% of the MPAs studied displayed only one or two key features and thus were not ecologically distinguishable from fished sites.
The results show that “global conservation targets based on area alone will not optimize protection of marine biodiversity. More emphasis is needed on better MPA design, durable management and compliance to ensure that MPAs achieve their desired conservation value.”