Posting in Energy
SmartPlanet visits an oyster nursery on Tomales Bay, where solar power will help maximize growth and decrease mortality.
MARSHALL, CA -- I’ve never much cared for them raw, smoked or grilled, but during a few days in this small town on Tomales Bay, 90 minutes north of San Francisco, I learned to like oysters. And after helping a friend work 50,000 of them in his oyster nursery, I have the beginning of a deep appreciation for the farming of this little mollusk.
The idea behind oyster farming—just like any type of farming—is that when you have some control over elements like temperature, water and nourishment, you can speed up the rate at which the animal grows. Here in Marshall, a town whose sign says its population is 50, oyster farming is big business.
Chris Starbird, a marine biologist who used to study sea turtles and island foxes, started Starbird Mariculture in 2007. I’ve known him since the years when he was a senior guide at Outward Bound and the National Outdoor Leadership School, and he invited me to join him for a couple days of oysters 101. In his fourth year of business, he’s making some infrastructure changes in response to lessons learned, including investing in alternative power so he can more efficiently and safely grow his oysters.
Starbird purchases seeds for Pacific oysters (Crassostrea gigas) from Washington State. At that point, they’re about two to three millimeters in diameter. Over a period of four to five months, he grows them to 18 millimeters (about 3/4 inch) and passes them along to the growers. Every year he sells millions of oysters locally to Tomales Bay Oyster Company and Hog Island Oyster Company.
Like most people, I’m infinitely more familiar with land farming than water farming. So when Starbird introduced me to aquaculture, I was surprised to learn that his operation is indeed a farm, in every sense. There’s the vocabulary (silo, trough), the list of unknowns that can make or break a season (weather, disease) and the unremitting list of strenuous and often precariously positioned tasks. (Pulling oysters out of the water into your boat sounds easy until you think about crane-lifting 500-pound trays of tens of thousands of oysters from the middle of the bay.)
Starbird first showed me around the command center next to the dock: a 60-by-25-foot flupsy, which is an acronym for floating upweller system. The upweller part features an underwater pump and a two-horsepower electric motor running a three-foot paddlewheel. The pump and wheel move water in a vertical plane through the seed bed, providing the nursery with continuous nutrients in the form of algae.
But the real fun happens in the middle of the bay. “Anyone can learn how oysters grow by looking online,” Starbird told me, as he steered his boat into the drizzle, “but the magic comes in knowing where to place them and growing the seed.”
Once the seeds reach a certain size, Starbird moves them to trays suspended underwater from a barge in the bay, about five miles north of the flupsy. Traditionally, oysters are grown in floating cylinders, but this suspension system, plus the rougher, faster-moving water in the bay, promotes growth. The trays are staggered underwater and supported by rebar frames; and the barges are positioned in a way that maximizes water flow in the channel.
The cooler water here also helps prevent disease. (One disease in particular, similar to the herpes virus plaguing oysters in France, has been detected in Tomales Bay during warmer months. During my visit, we delivered a bag of oysters to the U.C. Davis Bodega Marine Laboratory, where Starbird regularly brings the mollusks for testing.)
In the foggy bay, wearing foul-weather gear, we towed several stacks of trays onto the boat and brought them back to the flupsy. There, I helped send them through the tumbler, a machine that tosses the oysters around a bit (which helps strengthen their shells), washes them and sorts them by size.
The current process involves a lot of zipping around Tomales Bay and transporting oysters. But soon, Starbird will move the entire operation into the bay, where there is a reduced chance of losing oysters to disease. He says in two of the last three years his oysters have been hit with herpes. In late summer, when the water hits 70 degrees, he’s liable to lose millions of oysters to the virus.
The flupsy is mobile and can withstand five-foot waves, but moving into the bay also means moving away from the dock and the 300 kilowatt hours of electricity currently needed to run the operation every month. So Starbird is installing 14 solar panels this week, which will allow the system to operate completely off the grid. Starbird says when it’s complete, it will be the largest solar-powered flupsy in the country, perhaps the world.
By early afternoon, we had sorted all the oysters—some would return to the water to continue growing and some were ready to sell to the farms. I was exhausted watching my friend work. My straightforward tasks—boat-steering, crane-operating and tumbler-feeding—were complete. Grubby, chilled and starving, we walked next door to the Marshall Store, where we sat at the bar and indulged in hot chowder and a platter of grilled oysters. And for the first time, I ate them with pleasure.
Photos: Melanie D.G. Kaplan
Jun 21, 2011