THE BLUE REVOLUTION

Blue Revolution
by Marguerite Holloway, Photography by Kristine Larsen
published online September 1, 2002


View through an underwater camera used by technicians monitoring the release of food pellets at a salmon farm near Vancouver. About 50 percent of the protein in the pellets comes from fish meal and fish oil. "Farms are getting more efficient in controlling the amount of feed expended per fish," says aquaculture expert Rosamond Naylor. "But as the industry expands, it will require more wild fish to use as feed for farmed fish."
Last October, Stanford University economist Rosamond Naylor spent four hours flying over the southern part of the state of Sonora, which is half desert, half Sierra Madre mountains, in a crop-dusting plane borrowed for the outing. She was looking for evidence of inland shrimp farms, a burgeoning industry, and expected to find clusters of scattered ponds separated by huge tracts of sere land. Instead, it looked as if the Sea of Cortes had risen and swept across more than 42 square miles of the Sonoran: everywhere patches of blue, pools of shrimp, one after another, all down the coast. "It was so much more developed than I had thought," Naylor says. "The farms are right next to each other."
Over the course of a year, 95 percent of Mexico's farmed shrimp harvest—64 million pounds in 2000—makes its way to the United States. Most of the shrimp Americans consume come from abroad, and chances are excellent that they were farmed in Asia, Central or South America, or Mexico. We are also eating salmon raised on ranches that float in the seas off the coasts of Norway, Chile, Maine, and the Pacific Northwest. Slightly less than one-third of the seafood we consume is not wild at all, according to the U.S. Food and Drug Administration. It comes from aquaculture, a $52-billion-a-year global enterprise involving more than 220 species of fish and shellfish that is growing faster than any other food industry—so fast that fish farming is expected to exceed beef ranching within a decade.
This blue revolution could help solve some big problems. It could provide fish for an ever-growing number of consumers and more food for the 1 billion chronically malnourished people worldwide who need protein. And it could do so while saving rapidly disappearing wild fish by relieving the pressure of commercial fishing. But Naylor is one of a group of scientists and environmentalists who are not convinced that aquaculture is beneficial. She contends that in many places, the practice is destroying land along coasts and causing water pollution. And instead of helping save wild fish, she argues, aquaculture may actually be hastening their demise. "To say that aquaculture shouldn't happen at all would be wrong," she says. "But right now aquaculture is a slash-and-burn activity, shrimp farming in particular."
(A) A typical shrimp farm in the southern Sonoran Desert of Mexico covers nearly 250 acres. (B) Four-month-old shrimp will be harvested within another two months. (C) "Disease can spread quickly between closely linked ponds," says Naylor, on a tour with locals who fish for shrimp the old-fashioned way.
Naylor is convinced that these improvements could help the blue revolution succeed in areas where the green revolution failed. Given the diversity and global character of the industry, she has set her sights high. But consider this: She has seen a desert turn first green and now blue, and she has seen crustaceans swimming amid cacti. In the light of such wonders, anything seems possible.
Goldburg, Rebecca J., et al. "Marine Aquaculture in the United States: Environmental Impacts and Policy Options." Pew Oceans Commission, Arlington, Va., 2001. Available online at www.pewoceans.org/oceanfacts/2002/01/11/fact_22988.asp.

THE GIFT OF SALMON

The Gift of Salmon
In Alaska, biologists are learning that when wild salmon are free to swim upstream to spawn, dozens of other species flourish too
by Kathleen Dean Moore and Jonathan W. Moore, Photograph by Art Wolfe
published online May 1, 2003
My son and I splash upstream in hip boots, searching for signs of the sockeye salmon that return each summer to spawn and die in this wild Alaskan creek. I've come here to see for myself what he wrote home about last year:
The creek is so full of sockeye, it's a challenge just to walk upstream. I stumble and skid on dead salmon washed up on the gravel bars. It's like stepping on human legs. When I accidentally trip over a carcass, it moans, releasing trapped gas. In shallow water, fish slam into my boots. Spawned-out salmon, moldy and dying, drift down the current and nudge against my ankles. Glaucous-winged gulls swarm and scream upstream, a sign the grizzlies are fishing. The creek stinks of death.
These sockeye salmon are swimming upstream to spawn. In Alaska, salmon still abound, but in the lower 48 many runs have been decimated by dams, habitat degradation, and overfishing. The Columbia River in the Pacific Northwest was once teeming—2,112,500 salmon were caught in 1941; by 1998, the catch had dwindled to only 67,200 fish.

Jon's notes describe the feeding frenzy when the salmon are spawning: On the banks of the salmon stream, we come across bear kitchens, trampled ferns and grasses and decomposing salmon parts, where the bears dragged salmon to eat. Gulls have a hard time breaking open salmon skin by themselves, so flocks of gulls follow the bears, waiting to swoop in and swallow up leftovers. Gulls nest on exposed islands that quickly become littered with salmon bones. As the chicks grow fat, the island is whitewashed with digested salmon. Rain washes guano into the lake. Bald eagles rip into salmon and carry the food to their chicks. Caddis flies feed on salmon carcasses underwater, then hatch into adults that take to the air. Rainbow trout feed on salmon flesh that slowly breaks free from decomposing carcasses. Mink gorge on spawned-out fish. Trees grow rapidly with all this fertilizer. Tourists buzz in on floatplanes to fish, throwing the guts to gulls and freezing fillets in waxed cardboard cartons to be flown back to Tacoma or St. Louis.
www.sierraclub.org/wildlands/species/salmon.asp.
At least 66 species in the Pacific Northwest seek salmon for sustenance, feeding on the eggs, carcasses, and every life stage in between.