More Information

Meredith Elliott


Senior Scientist, California Current Group

Assessment of Marine Protected Areas in the California Current

Executive Summary

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The California Current System is one of the most productive marine environments in the world. High productivity is the result of coastal wind driven upwelling that brings deep, cold, nutrient rich water to the surface of the ocean, thus enhancing primary production. The California Current extends from Vancouver to Baja California, and like other eastern boundary currents, it hosts biologically important species, supports important economic activities and is adjacent to increasing human populations.

Economic activities like fisheries, aquaculture, shipping and recreation impact the marine environment in which they take place. To mitigate these impacts and to protect marine biodiversity, ecosystem services and cultural values, marine managed and/or protected areas (herein Marine Protected Areas or MPAs) with specific goals have been established throughout the California Current System. There are approximately 390 MPAs along the U.S. West Coast representing varying levels of protection from fishery management areas that prevent specific fishing practices to fully protected no-take reserves.

We conducted a Marine Protected Area (MPA) assessment to understand the status of current spatial management approaches and to identify opportunities to better protect marine biodiversity in the California Current System. Our analysis focused on four main tasks, the results of which are presented in this report:

  1. A spatial assessment of regulations and protections for existing MPAs.
  2. A spatial analysis of how well priority species (e.g., anchovies, sardines) and habitats (e.g. kelp, seamounts) are represented in MPAs.
  3. A spatial assessment of major threats impacting existing protected areas.
  4. Based on the above, identification of opportunities for improving conservation.


Very little of the California Current is highly protected. Most MPAs are in federal waters and are listed as uniform multiple use areas, which means in practice limited protection, usually focused on specific activities or a single type of species. Only 6% of the EEZ is protected by zoned multi-use areas (moderate protection), one half of one percent is zoned for no take areas (moderately high protection), and less than a quarter of one percent is entirely no take (high protection). State MPAs are important in the California Current. Though they cover relatively little of the total extent of the California Current, the small areas they do encompass tend to represent very high conservation value and State MPA protections offered tend to be relatively strict.

A relatively low percentage of the suitable habitat for the species we examined is well protected. On average, only 2 – 3% of a species’ total suitable habitat was in MPAs with moderate or better protection. As expected, due to the limited number of MPAs in Oregon, much less priority habitat is included there relative to California and Washington. Priority species as indicated by Elliott et al. 2019 are, in general, well-represented in existing MPAs and existing MPAs do a good job in focusing on high-quality habitat for the species we examined.

Of all the threats examined here, climate change is having the largest impacts on our oceans. MPAs in the California Current will be substantially impacted by climate change-related ocean acidification and increases in ultraviolet radiation; increases in sea surface temperature are also projected to have a major impact. Due to the global scale of climate change, management entities that exist on local and regional scales like MPAs are not likely to be effective solutions for climate impacts.

The cumulative impacts of commercial and recreational fishing are substantial in the California Current. Fishing is also the most regulated of human activities in the California Current, both through spatial restrictions and fishery-wide regulations. Recreational fishing is an area that needs additional regulation. It is a human activity that has great magnitude in terms of impact and, unlike commercial fishing, very few restrictions. Shipping is another impact of concern, with a high index of impact, yet few restrictions. Less than 5% of the Exclusive Economic Zone (EEZ) has restrictions on vessel traffic and less than a twentieth of a percent of the EEZ is closed to shipping.


Strengthening regulation in existing California Current MPAs would offer significant conservation benefits and is potentially more feasible than establishing new MPAs. Existing spatial regulations cover over half of the California Current, offering opportunities to increase protection in already regulated areas. Expanding the protective focus of some of these MPAs that are currently focused on single-species protection to ensure sustainable protection (e.g., the groundfish FMP) would have substantial conservation benefits.

Clarifying MPA boundaries and simplifying marine governance structure would make it easier for individuals to comply with marine regulations and easier for governments to enforce them. The California Current is governed by dozens of regulations and agencies. Because of this, it is often difficult to determine the exact restrictions that apply to a given area. This is especially true in areas of overlapping jurisdictions, in which multiple MPAs govern the area.

Expanding the nearshore area protected by MPAs would provide the greatest conservation value for the least area protected. State MPAs are important in the California Current. Though they cover relatively little area, the area they include tends to be of very high conservation value and the actual protections offered tend to by relatively strict.

Increasing environmental protection in areas in and adjacent to existing nearshore MPAs would have significant conservation benefits. Coastal MPAs are also the most vulnerable to human impacts of all MPAs examined. Nearshore impacts from human development are numerous (e.g., pollution, nutrient runoff, sedimentation, light pollution) and cumulatively have a very large impact on habitat suitability.

Spatially, the rocky banks of the Oregon Coast would be a strategic choice for the creation of new MPAs. There is a large gap in existing MPAs from Northern California through Southern Washington. Oregon has very few MPAs in its state waters and there is a corresponding gap in federal MPAs. Moreover, this area boasts highly suitable habitat for most of the species examined in this report, and coastal Oregon consistently ranked highly in our prioritization of conservation value. In particular, the water from Heceta Bank to Cape Blanco were zoned as being of very high conservation value.

National Marine Sanctuaries in the California Current are areas of high conservation value. They are also impacted by many local human activities that could potentially be regulated. Sanctuaries are generally less impacted by land-based activity (with the notable exceptions of sediment runoff and climate change), so regulation of the sanctuaries themselves can have more influence on overall ecosystem health. Increasing the regulation of commercial fishing would have benefits for all sanctuaries, as would zoning portions of the sanctuary as no-take areas. Olympic Coast National Marine Sanctuary (NMS) would benefit from additional restrictions on commercial fishing. All sanctuaries except for Olympic Coast NMS are substantially impacted by shipping traffic, so redesigning shipping lanes and/or restricting dumping (especially from cruise ships, which have exemptions under many NMS regulations) would be helpful. Olympic Coast is less affected by human impacts and is a good candidate for preservation from future potential impacts. It is also a good candidate for expansion, as adjacent areas have a high conservation value.

Of the habitats examined, our analysis found seamounts to be of high conservation value. Seamounts, designated as Habitat Areas of Particular Concern by and for regional fisheries management, provide unique habitat for many species. They are also relatively rare habitats. While most seamounts do occur within existing MPAs, these are MPAs that do not have major restrictions on human activity vis-à-vis seamount habitats and many of the species that use them. Strengthening the protection of seamounts in the California Current would have significant conservation benefits relative to the total area protected.

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