Exploring California’s Marine Protected Areas: Farnsworth Onshore State Marine Conservation Area and Farnsworth Offshore State Marine Conservation Area

Located around 20 miles off the Southern California mainland, Santa Catalina Island is a popular destination for those looking to enjoy island living. Kayak tours, glass bottom boats, jet ski excursions, and snorkeling and scuba diving opportunities await the numerous visitors who venture here every year.

Map of all nine Santa Catalina Island MPAs (click to enlarge).
Image created by CDFW GIS lab

Most visitors to Santa Catalina will go to Avalon, the only incorporated city on any of California’s eight Channel Islands. Avalon has been a popular tourist destination since the 1920s and remains a hub for most island activities. Flanked on either side by two small marine protected areas (MPAs), visitors to Avalon can easily access and explore Casino Point State Marine Conservation Area (SMCA) and Lover’s Cove SMCA. These are just two of Santa Catalina’s nine MPAs, which are part of a much larger statewide MPA Network spanning California’s coast.

Santa Catalina averages over one million visitors every year, with the majority typically spending their time in Avalon or the nearby town of Two Harbors. Both Avalon and Two Harbors are on the protected, leeward side of the island, facing the mainland. While the Pacific Ocean is famously cold off of California’s coast, the waters on the protected side of Santa Catalina tend to be some of the warmest in Southern California, and offer beginner and novice scuba divers suitable locations to experience the spectacular marine life that thrives around the island. However, for advanced divers looking to explore areas a bit more removed from popular tourist spots, there’s no better place than on the exposed “backside” of Santa Catalina at Farnsworth Bank.

Farnsworth Bank is part of a series of tall, hard, bedrock pinnacles that peak near a depth of 50 feet and plunge dramatically towards a soft, sandy seafloor. The bank is protected by two MPAs, Farnsworth Onshore SMCA  and Farnsworth Offshore SMCA, as well as Farnsworth Bank Area of Special Biological Significance. Nearly impossible to access from shore, and challenging to visit by boat due to their remote location and constant exposure to open ocean swells, the two SMCAs are not the most frequently visited MPAs in California’s MPA Network. But when timed correctly, during the more favorable conditions of late fall and early winter, scuba divers descending into these waters can expect an underwater treat.

The popular dive site at Farnsworth Bank is located more than one mile west of Santa Catalina in the larger of the two MPAs, Farnsworth Offshore SMCA. This MPA replaces and expands upon a previous, smaller protected area named Farnsworth Bank SMCA, which was established in 1972 to prevent the collection of purple hydrocoral (Stylaster californicus). Many divers seek out this site specifically to view the unique hydrocoral.

Uncommon throughout Southern California, purple hydrocoral occurs most frequently at Farnsworth Bank, Tanner-Cortes Bank, Cordell Bank, and at San Clemente Island. These locations feature relatively clear water (low turbidity) and strong currents, conditions in which purple hydrocoral appears to thrive. In addition to being uncommon, purple hydrocoral is slow-growing, averaging less than one-quarter inch per year, and is easily broken due to its brittle nature. While purple hydrocoral is not a reef-building coral such as those common in tropical waters, it still provides valuable habitat for numerous fish and invertebrate species wherever it is found.

Ca. scorpionfish
California scorpionfish camouflaged against colorful reef habitat

Between pockets of purple hydrocoral, Farnsworth Bank contains an explosion of color and life. Strawberry anemones add bursts of pink, green blades of kelp rise into the water column, red and golden gorgonians sway in the current, and colorful sponges fill the spaces in between. Divers may be surrounded by schools of mackerel and sardines, with yellowtail and California sea lions zipping around while hunting the bait fish. Blacksmith and California sheephead live on the rocky reef, moray eels are found tucked into their rocky homes, and torpedo rays cruise among the pinnacles. California spiny lobster shelter within rocky crevices during the day, and small nudibranchs and bluebanded gobies add extra color to the already amazing displays of marine life.

While both MPAs do allow for some types of fishing, fishermen should note that this area may be a bit difficult to fish due to the layout of the bank. Scuba divers frequently report finding snagged and lost gear throughout the dive site. If you do decide to fish at Farnsworth Bank, make sure you have a fishing license and check the specific regulations for each MPA before heading out!

These remote MPAs may not be on the top of your list to visit, but Farnsworth Onshore SMCA and Farnsworth Offshore SMCA are valuable segments of the California MPA Network. They protect a variety of habitats, from the shore to depths greater than 1,900 feet, including diverse rocky intertidal habitats, sandy plains, deep water pinnacles, and offshore reef. If you want to get a glimpse of all that the SMCAs have to offer, watch this video from the comfort of home. You may find yourself enticed to visit in person, to experience first-hand the thriving marine life found within them!

Farnsworth Onshore State Marine Conservation Area and Farnsworth Offshore State Marine Conservation Area are two 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.

MPA logopost by Amanda Van Diggelen, CDFW Environmental Scientist

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