Ocean Sanctuaries Are a Boon for Fish, Seabirds, and Marine Mammals
The MLPA, passed in 1999, requires the state to redesign its marine protected areas—much like national parks in the sea—along California’s 1,100-mile coastline. The marine reserves established since the 1950s were too small and too isolated to support biodiversity. The new science-based refuges are now in place in four coastal regions, with the fourth, the north coast where Jensen has been hard at work, approved in June. Before the redesign, 80 marine protected areas covered 172 square miles; now there are 124 spread over approximately 845 square miles. The fifth and final region, San Francisco Bay, is on hold pending further planning efforts.
The reserves were designed to allow fish, seabirds, coral reefs, kelp forests, and other sea life to thrive with minimal disturbance in a variety of habitats. Jensen compares the protected areas to a savings account you use to create a buffer. “Basically the intent of the MLPA is to build in that cash reserve for the ocean so that you’re not living paycheck to paycheck out there, so that we don’t have groundfish stocks that are just barely sustainable,” he says. “Because they will crash. Maybe it’s great this year. But we’re two bad summers away from a total catastrophe.”
That could spell disaster for the entire food chain. Several studies show that the reproductive success of seabirds rests on the availability and abundance of food. When fish abound near shore, coastal birds’ foraging trips are shorter and more successful. Marine reserves harbor more fish and allow long-lived ones—like rockfish species that need 20 years to reach reproductive maturity and can live for more than a century—to grow larger, which leads to more robust populations. “Doubling rockfish size is probably a bigger conservation benefit than doubling the number,” says Don Croll, a University of California-Santa Cruz marine conservation biologist. And mounting evidence indicates that healthier populations within the reserves have a spillover effect, benefiting not only the species in the protected areas but also strengthening fish populations outside their borders.
On a bright, crisp September morning we set out to get a firsthand look at some of the areas that will be protected and the wildlife that will benefit, including local seabirds and long-distance voyagers that travel here from as far away as Hawaii and New Zealand to feast in these bountiful waters. The pungent smells of sea salt and raw fish fill the air in the sleepy seaside town of Crescent City, California, just 20 miles south of the Oregon border. Our boat guide, Craig Strong, a tall, soft-spoken seabird biologist who has studied these birds since he was 12 years old, is a member of the MLPA science team. Audubon’s Weinstein, a conservation biologist known for her frank manner and fierce championing of seabirds, is also aboard, her hair pulled back loosely with wispy curls framing her face.
This rugged coastline, studded with rocky domes, spires called “sea stacks,” and craggy cliffs, provides some of the world’s most important seabird nesting habitat. Early in the morning Strong guides our boat past Castle Rock National Wildlife Refuge, a 14-acre island that juts steeply out of the water and is one of seven proposed “special closure” areas. Under the new regulations, boats aren’t allowed within 300 feet, providing a buffer for the skittish birds that raise their young here. Castle Rock is one of the largest nesting seabird colonies in the lower 48 states, providing critical habitat for roughly 120,000 seabirds, representing 13 species. It possesses diverse habitat niches, each perfectly suited to a particular bird’s lifestyle. Pelagic cormorants nest on steep cliff faces to minimize predation, using the incline as a runway for takeoff. Cassin’s auklets and rhinoceros auklets find safe haven for their eggs by digging burrows in the dirt, tucked far away from cliff sides, or by nesting in rock crevices.
The protective zone around Castle Rock is particularly important for species like common murres and Brandt’s cormorants. They’re closely tied to their breeding colonies and rely heavily on juvenile rockfish, sardines, anchovies, and krill in these near-shore waters throughout the year. As we pass by, penguin-like common murres glide down from their perches, likely embarking on foraging trips during which they’ll dive tens to hundreds of feet deep for a meal. Weinstein is closely involved in designating Castle Rock and nearby False Klamath Rock as “global” Important Bird Areas, which will take effect this year. Global IBAs either host species that are considered significant because they’re rare or in decline or are home to an unusual multitude and diversity of birds. “The north coast IBAs are precedent-setting and among the first,” says Weinstein.