Exploring California’s Marine Protected Areas: Sea Lion Cove State Marine Conservation Area

The Point Arena Lighthouse is a popular landmark to visit along California’s picturesque Mendocino Coast. Standing 115 feet above the flat coastal prairie, the lighthouse rises from the headland’s edge, bravely overlooking the pounding waves below. Whether from the top of the lighthouse or from the grounds, visitors marvel at the expansive ocean views surrounding them on all three sides.

While most who come here will appreciate that the land is preserved for its historical significance and natural beauty, they might not know that the local ocean waters are protected too. In 2010, California established three marine protected areas (MPAs) near the lighthouse: Point Arena State Marine Reserve (SMR), Point Arena State Marine Conservation Area (SMCA), and Sea Lion Cove SMCA.

In 2015, federal protections followed suit with the boundary expansion of the Gulf of the Farallones National Marine Sanctuary. Now renamed the Greater Farallones National Marine Sanctuary, it has more than doubled in size and includes the nutrient-rich waters and diverse marine habitats off the coast of Point Arena.

Point Arena State Marine Reserve, Point Arena State Marine Conservation Area, and Sea Lion Cove State Marine Conservation Area (click to enlarge)
CDFW map by Marine Region GIS Lab

Compared to Point Arena SMR and Point Arena SMCA, Sea Lion Cove SMCA is very small, covering only about a quarter square mile to the south of the lighthouse. Its boundaries stay close to shore and extend from the mean high tide line out to a depth of about 39 feet. Unlike Point Arena SMR where take of marine resources is not allowed, or Point Arena SMCA where only salmon trolling is allowed, the regulations at Sea Lion Cove SMCA are more permissive. Finfish, such as rockfish and surfperch, can be taken in this MPA, while protection is focused on marine invertebrates, seaweeds and seagrass, as well as geological and cultural marine resources. In particular, Sea Lion Cove SMCA was designed to protect abalone and the resources that support their populations.

Abalone are marine gastropods, or sea snails. They are prized for their meat, which is considered a delicacy, and the iridescent mother-of-pearl lining inside their shells. Found in shallow rocky reef and kelp forest habitats, abalone are oftentimes hard to spot because they clamp down onto rocks and blend in extremely well. Their oval shells have a low profile with a distinctive row of holes lined up along one edge. Short, delicate tentacles feel around under the outer lip of their shells, fluttering through the water like eyelashes.

red abalone
Red abalone
CDFW photo by A. Maguire

California is home to the world’s largest species of abalone, the red abalone (Haliotis rufescens). They are a long-lived and slow-growing species but can grow up to 12 inches in length, big enough to cover a standard sheet of paper! While there are seven other species of abalone in California, only the red abalone has been abundant enough in recent years to support a recreational-only fishery. A niche tourism industry developed around the recreational red abalone fishery north of San Francisco, drawing thousands of abalone divers and rock-pickers, and bringing in millions of dollars in revenue to the North Coast each year.

Sea Lion Cove SMCA was established in 2010 to carve out a small area where abalone populations would hopefully grow and multiply, untouched by the fishery. Fishery managers knew this site had potential because abalone used to thrive in these waters back when the mainland was privately owned. From 1917 to 2004, the land adjacent to Sea Lion Cove SMCA belonged to the Stornetta family ranch and dairy, which blocked public access to the coast and limited abalone harvest. In 2004, conservation agencies including the Wildlife Conservation Board, Coastal Conservancy, U.S. Fish and Wildlife, and The Nature Conservancy collectively purchased the land and turned it over to the Bureau of Land Management to manage as the Point Arena-Stornetta Public Lands. Although a victory for public lands advocates, once public access was granted to this stretch of coastline the red abalone population declined by approximately 70 percent in just three years. Sea Lion Cove SMCA aimed to restore protection for red abalone, and after several years California Department of Fish and Wildlife (CDFW) scientists observed higher densities of red abalone in the Point Arena area.

However, more recently, a “perfect storm” of compounding environmental shocks has decimated kelp forests along the North Coast, along with the abalone populations that depend on them for food and habitat. This ecosystem collapse triggered a statewide closure of the recreational red abalone fishery in 2018, continuing through at least 2021.

MPAs are not immune to significant environmental changes, and Sea Lion Cove SMCA was hit hard. These days, marine ecosystems face multiple challenges, including temperature stress, changing ocean chemistry, pollution, and fishing pressure, among other stressors. MPAs may be able to help address some of these concerns but have limited influence on others. They serve as a complementary management tool that can be used to increase the effectiveness of overall conservation objectives. Sea Lion Cove SMCA continues to offer protection for invertebrates and seaweeds which, in addition to the abalone fishery closure, may further encourage abalone population recovery. CDFW scientists have partnered with researchers at UC Santa Cruz to monitor abalone populations at Sea Lion Cove SMCA and other locations along the North Coast.

Sea Lion Cove
A rocky path emerges to Sea Lion Rocks on very low tides
CDFW photo by C. Shen

In the meantime, Sea Lion Cove SMCA and the adjacent Point Arena-Stornetta Public Lands still hold much of their appeal. Tour the edge of Sea Lion Cove SMCA by following the 1.2-mile section of scenic trail from Lighthouse Road to the Mendocino College Coastal Field Station. This hike is set against a breathtakingly rugged backdrop of rocky isles and platforms, sea arches, sea caves, and sinkholes broken up and carved out by the dynamic forces of nature. California’s infamous San Andreas Fault runs along the margin of the North Coast and cuts through Point Arena, leaving geologic signatures at the boundary between the Pacific Plate and the North American Plate. Relentless wave action and periodic tectonic activity have slowly warped this landscape over time. In a few spots along the trail, steep access points lead down to the Sea Lion Cove SMCA shoreline. At low tide, you can find abalone, sea cucumbers, and ever-increasing numbers of purple sea urchins. While tidepooling, take care to look where you step to avoid harming any living things in the MPA. On especially low tides, you can even cross an uneven rocky path all the way out to Sea Lion Rocks, usually separated from the mainland by the ocean, but make sure to beat the incoming tide on your way back!

In 2014, the Point Arena-Stornetta Public Lands were incorporated into the California Coastal National Monument and identified by the New York Times as one of the top places to go. This area offers incredible hiking, tidepooling, and whale watching opportunities. Located a 3½ hour drive north of San Francisco, at Sea Lion Cove SMCA you’ll find yourself in a place where the ocean feels truly wild.

Sea Lion Cove State Marine Conservation Area is one of the 124 MPAs in California’s statewide MPA Network. Please visit CDFW’s MPA website for more information, and sign up to receive updates about the MPA Management Program.

logo post by Chenchen Shen, CDFW Environmental Scientist


Learn more about MPAs by diving into the
Exploring California’s Marine Protected Areas series!