Ocean ecosystems contain diverse species and so protecting multiple inhabitants in a large area is more effective than protecting each species or group individually (Gell, 2003; Russ, 2008). Protecting complete ecosystems allows animals to reach their maximum reproductive potential and enables increases in population size. Beyond the protected boundaries, healthy populations can spread out into adjacent waters, increasing the biomass surrounding those protected areas and bolstering local fisheries (Lester et al., 2009; Edgar et al., 2014). These refugia strengthen ecosystems by keeping natural processes intact and enhancing resiliency for their inhabitants. Research suggests that strategically created networks of marine protected areas can help valuable ocean systems survive the uncertainty of global climate change by alleviating additional stress from overfishing, habitat destruction, or marine pollution (Olds, 2014; Micheli, 2012).
Marine protected area (MPA) coverage is commonly used as a metric of progress for the marine conservation movement. Reporting the extent to which governments are contributing toward global MPA targets (e.g., the IUCN World Parks Congress recently call for a global target of 30% MPA coverage), provides accountability and frames individual progress within this larger context.
However, not all marine protected areas are created equal. There are thousands of places governments and regulatory bodies have termed “marine protected areas” but are very poorly protected in practice (Mora, 2011). Protection needs to be strong to be effective and to enable ecosystems to receive the most important benefits. Many existing marine protected areas guard against only a few threats, and most allow people to fish within them. No-take marine reserves provide the strongest level of protection, and safeguard marine life from the harmful effects of fishing and other extractive uses, such as drilling for oil and gas (Edgar et al., 2014).
|MPA Name||Area (km2)|
|Papahānaumokuākea Marine National Monument||1,146,565|
|Pacific Remote Islands Marine National Monument||1,270,000|
|Ross Sea (general protection area)*||1,117,000|
|Pitcairn Islands Marine Reserve||834,334|
|Kermadec Ocean Santuary*||620,000|
|Chagos Protected Area||545,000|
|Rapa Nui Rahui MPA*||496,570|
|Phoenix Islands Protected Area (PIPA)||408,000|
|Nazca-Desventuradas Marine Park||297,518|
|Ascension Island Ocean Sanctuary*||234,291|
|Motu Motiro Hiva Marine Park||150,000|
|Terres Australes Francaises (core zone)||120,000|
|South Orkney Islands Southern Shelf Marine Protected Area||94,000|
|Russian Arctic National Park||66,000|
|Heard Island and McDonald Islands Marine Reserve||64,000|
* Officially designated, but not yet implemented.
Strongly protected marine reserve coverage varies by nation and across the globe. As of 2016, only 1.6% of the ocean is within strongly protected reserves (MPAtlas, 2016). The nine implemented areas listed above account for more than 80% of global strongly protected area. Since 2013, we have released a series of reports detailing the extent of these strongly protected areas within the United States, the “Group of Twenty,” or G20 (an international forum representing the 20 largest national economies) and among the countries of North America.