South Cape Mendocino State Marine Reserve, Sugarloaf Island Special Closure, and Steamboat Rock Special Closure

Basket stars on the sea floor in South Cape Mendocino SMR

Overview

Located along northern California’s Lost Coast (one of the largest stretches of undeveloped coast in California) South Cape Mendocino State Marine Reserve (SMR) and the adjacent Sugarloaf Island and Steamboat Rock special closures lie between the towns of Petrolia and Capetown. The SMR protects around nine square miles of ocean habitat and spans more than a mile of remote coastline. Sugarloaf Island is a rocky offshore sea stack that juts out of the rough Pacific waters to the north of the SMR. Steamboat Rock is about two miles south of Sugarloaf Island at the southern edge of the SMR. South Cape Mendocino SMR reaches depths greater than 270 feet and features sandy and rocky seafloor habitat, and black sand beaches. The beach is a short walk from the closest road, Mattole Road.

The Lost Coast is known for a beautiful ruggedness enjoyed by hikers and travelers. This isolated stretch of coastline and rough offshore waters protect invertebrates such as abalone, acorn barnacles, California mussels, and ochre sea stars, and provide resting and hunting grounds for marine mammals including orcas, sea lions, and seals. Bring binoculars to view sea stacks filled with local wildlife at Sugarloaf Island Special Closure and Steamboat Rock Special Closure. You may see Steller sea lions and any of the estimated 10,000 seabirds that live on Steamboat Rock, including common murres, pigeon guillemots, and Brandt’s cormorants. 

Regulations

South Cape Mendocino SMR

It is unlawful to injure, damage, take, or possess any living, geological, or cultural marine resource.

California Code of Regulations Title 14, Section 632(b)(11)(opens in new tab)

Sugarloaf Island Special Closure 

Boating and access are restricted. Except as permitted by federal law or emergency caused by hazardous weather, no vessel shall be operated or anchored at any time from the mean high tide line to a distance of 300 ft. seaward of the mean lower low tide line of any shoreline of Sugarloaf Island, year round. 

No person except employees of the California Department of Fish and Wildlife, United States Fish and Wildlife Service, National Oceanic and Atmospheric Administration, or United States Coast Guard during performance of their official duties, or unless permission is granted by the California Department of Fish and Wildlife, shall enter the area. 

California Code of Regulations Title 14, Section 632(b)(10)(opens in new tab)

Steamboat Rock Special Closure 

March 1 to August 31 only:

Boating and access are restricted. Except as permitted by federal law or emergency caused by hazardous weather, no vessel shall be operated or anchored from the mean high tide line to a distance of 300 ft. seaward of the mean lower low tide line of any shoreline of Steamboat Rock. 

No person except employees of the California Department of Fish and Wildlife, United States Fish and Wildlife Service, National Oceanic and Atmospheric Administration, or United States Coast Guard during performance of their official duties, or unless permission is granted by the California Department of Fish and Wildlife, shall enter the area. 

California Code of Regulations Title 14, Section 632(b)(12)(opens in new tab)

Quick Facts

South Cape Mendocino SMR

MPA size: 9.08 square miles

Shoreline span: 1.4 miles

Depth range: 0 to 277 feet

Habitat composition:

  • Rock: 5.33 square miles
  • Sand/mud: 5.03 square miles

Sugarloaf Island Special Closure 

Special Closure size: 0.02 square miles

Depth range: 0 to 10 feet

Habitat composition:

  • Rock: 0.04 square miles
  • Sand/mud: less than 0.01 square miles

Steamboat Rock Special Closure

Special Closure size: 0.02 square miles

Depth range: 0 to 22 feet

Habitat composition:

  • Rock: 0.05 square miles

Photo Gallery

Video Gallery


California's MPA Network

About South Cape Mendocino State Marine Reserve, Sugarloaf Island Special Closure, and Steamboat Rock Special Closure

Natural History

View of Steamboat Rock special closure
Steamboat Rock Special Closure lies just offshore of Black Sands Beach. photo © C. Allison, MPA Collaborative Network

Cape Mendocino, just to the north, is situated farther west than any other part of the California coast. This region is one of the most seismically active in the contiguous United States. Just offshore lies a geologic triple junction, the location where three tectonic plates meet. The black sand beaches prevalent along this stretch are derived from greywacke, a type of dark sandstone. There are prominent rock outcroppings along the north and south ends of the SMR, including two sea stacks protected by special closures: Sugarloaf Island and Steamboat Rock. 

Beneath the surface, sandy and rocky seafloor habitats are interspersed from the shoreline to deeper offshore waters, providing habitat for many species including bull kelp, red abalone, rockfish, and lingcod. This SMR is especially important as a rookery for sea lions and seabirds. Many different species of birds including Brandt’s cormorants, tufted puffins, common murres, western gulls, and black oystercatchers can be found. Depending on the season, you may be able to see gray, blue, and humpback whales pass along this stretch of isolated northern California coast during their long migrations.

Cultural History

Gumboot chiton
The original inhabitants of this area, the Mattole people, collected mollusks, like this gumboot chiton, from the rocky intertidal zone. photo © pretzelle, CC BY-NC 2.0

For centuries, Native American Tribes in California have relied on marine and coastal resources. Many Native American Tribes in California continue to regularly harvest marine resources within their ancestral territories and maintain relationships with the coast for ongoing customary uses. The road that runs along the SMR was named after the Mattole Tribe, the indigenous people of this area. The Mattole people harvested food from the sea, including salmon and mollusks. Many Native Americans were displaced when European settlers arrived, but today the Bear River Band of Rohnerville Rancheria exists as a federally recognized tribe, with cultural roots in Cape Mendocino.  

In 1867, a ship ran aground along this unforgiving stretch of coast while attempting to deliver building materials for a lighthouse. Despite setbacks, the lighthouse was completed in 1868. The 43-foot tower was one of the tallest lighthouses in the U.S. at 422 feet above sea level.  However, in the 1960s the lighthouse was abandoned, and began deteriorating and slipping down the hillside. Later, the lighthouse was moved thirty miles south to Shelter Cove, where it was opened in 2001 and remains an often-visited place today. 

The MPA coastline remains a relatively isolated region that receives little foot traffic, and as such can be appreciated as a preserved example of northern California’s natural beauty.

Recreation

Bicycle on Mattole Road overlooking ocean and Sugarloaf Island
Mattole Road rewards those who make the trek with stunning views of the Lost Coast. photo © J. Palmer, CC BY-SA 2.0

The coast around Cape Mendocino is a great place to visit for those willing to make the journey. The SMR and adjacent Black Sands Beach can be accessed from Mattole Road, one of the few roads on the entire Lost Coast and the only road that winds along the coastline here. Steamboat Rock is directly offshore from Black Sands Beach, which is typically devoid of people and dotted with driftwood and small rocks. 

The road yields stunning views of this desolate coastline, including cattle and horses grazing on the coastal grasses, waves slapping the black sand beaches, and birds flocking to rocky outcroppings like Sugarloaf Island. Though the take of any marine resources is prohibited within the SMR, visitors can still enjoy the breathtaking landscapes and witness large populations of sea lions basking on the shore. 

 

Coordinates

South Cape Mendocino SMR

This area is bounded by the mean high tide line and straight lines connecting the following points in the order listed except where noted:

40o 26.100 ′ N. lat. 124o 24.340 ′ W. long.;
40o 26.100 ′ N. lat. 124o 31.958 ′ W. long.; thence southward along the three nautical mile offshore boundary to
40o 24.900 ′ N. lat. 124o 31.084 ′ W. long.; and
40o 24.900 ′ N. lat. 124o 23.800 ′ W. long.

California Code of Regulations Title 14, Section 632(b)(11)

Sugarloaf Island Special Closure

A special closure is designated from the mean high tide line to a distance of 300 feet seaward of the mean lower low tide line of any shoreline of Sugarloaf Island, located in the vicinity of 40o 26.326 ′ N. lat. 124o 24.827 ′ W. long.

California Code of Regulations Title 14, Section 632(b)(10)

Steamboat Rock Special Closure

A special closure is designated from the mean high tide line to a distance of 300 feet seaward of the mean lower low tide line of any shoreline of Steamboat Rock, located in the vicinity of 40o 24.919 ′ N. lat. 124o 24.241 ′ W. long. during the period of March 1 to August 31.

California Code of Regulations Title 14, Section 632(b)(12)

South Cape Mendocino State Marine Reserve

Map

Map of South Cape Mendocino State Marine Reserve - link opens in new window

Facts, Map & Regulations

MPA fact sheet

Sugarloaf Island Special Closure

Map

Map of Sugarloaf Island Special Closure - link opens in new window

Facts, Map & Regulations

MPA fact sheet

Steamboat Rock Special Closure

Map

Map of Steamboat Rock Special Closure - link opens in new window

Facts, Map & Regulations

MPA fact sheet