Ocean Sanctuaries Are a Boon for Fish, Seabirds, and Marine Mammals
A chain of more than 100 Marine Protected Areas offer a safe haven for creatures from albatrosses to whales along California's 1,100-mile coastline.
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.
As we reach the northernmost point of our boat trip, eight miles from our launch, we're greeted by a raucous cacophony of barks, belches, growls, and harps emanating from the congregation of seals and sea lions on the rocks surrounding the St. George Reef Lighthouse, some seven miles offshore. At least 30 humpback whales swirl around us, their mighty bodies generating waves that rock our cozy, 21-foot boat, making it feel downright inadequate. Strong cuts the engine, and for nearly an hour we take in the heaves and blows and the lunges and crashes of breaching whales, some close enough to our boat that we can see barnacles clinging to their flippers. Upwelling from the California Current, a cold-water conveyor belt that extends from southern British Columbia down to Baja California, draws decaying organic matter and nutrients such as nitrate and phosphate from deep water and delivers them to these shallow, near-shore waters. This, in turn, drives the bounty of phytoplankton, krill, and fish on which the whales beneath us are feeding.
Amid the bustle, the seabirds busy themselves around us. A handful of potato-sized Cassin's auklets skid across the surface, bouncing and surfing on the calm sea. Two marbled murrelets, federally listed as a threatened species, bob on the water and then dive for a meal of bite-sized krill, sardines, or Pacific herring. A lively conversation of throaty caws and shrill chirps ensues between a common murre father and his nearly fledged chick. This chatter is "a vital lifeline before the chick can feed itself," says Strong.