Starting every year in the late spring, a fleet of boats, aided by spotter planes, catches and hauls fish back here for systematic fattening and eventual slaughter.
Unlike meat sources such as beef, pork or even salmon, which are bred and farmed, even ranched tuna must be considered a "wild" animal source. Bluefin tuna, which average 600 pounds at maturity, are notoriously difficult to breed in captivity, and thus, ranches such as Baja Aquafarms must catch wild tuna, only to fatten them up to increase the yield of meat. But because the fishermen are taking from an already depleted population of fish, the sustainability of such practices is questionable.
Still, Umami, which reported sales of $42 million in the fiscal third quarter ending March 31, with a profit of $10 million, says its operations have lessened its environmental footprint.
"Our operations are fundamentally different from other operations in the way that we farm the fish longer," Jonsson says. "The amount of fish we have to catch from the ocean is less, and the overall utilization of natural resources is better."
He points out that ranches once would feed an individual bluefin only for a few months, but they are now fed for up to three years to weights of close to 300 pounds — minimizing the number of individual fish that need to be caught while maximizing each fish's yield of flesh.
Javier Vivanco has managed the daily operations at Baja Aquafarms for a decade. He pulls up to the young adult pens to give the tuna their second feeding of the day. The bluefin boil up to the surface clockwise while a legion of sea lions bark and dive for scraps.
"We're not using pellets of artificial feed. We're using real food — the natural feed source of the bluefin," Jonsson says as he motors out of the San Diego harbor.
Fresh, locally caught sardines are shoveled into the pens daily by the boatload. Jonsson touts Umami's feed conversion ratio — the weight of feed mass converted into body mass — as 17 to 1, meaning it takes 17 pounds of sardines to make a single pound of bluefin flesh in these waters off Baja.
By comparison, according to Monterey Bay's Bridson, farmed salmon require 3 to 4 pounds of feed per pound of weight gain. "The bluefin is very energy intensive," he says. "It's more like a Ferrari than a Toyota Prius in that respect. It's a really difficult species to ever grow sustainably."
But Jonsson is quick to note that in the wild, bluefin take nearly twice the toll on bait fish, eating 30 pounds for every pound of growth.
While Umami highlights its measures of sustainability, it is working on developing a "closed-loop cycle," the process of spawning bluefin in captivity and raising them to market maturity. But this is a project in its infancy. To date, only Kinki University in Japan, a pioneer in aquaculture, has been able to successfully hatch bluefin eggs in a lab, raise the fish — known as kindai — and sell the mature fish commercially. With three generations of fish spawned in captivity, Kinki no longer needs to take fish from the sea.
Although the closed-loop cycle for bluefin may represent the last best hope for saving the species, even this is not a long-term solution, according to Monterey Bay's Bridson. "The best way to be eating bluefin is to reduce our consumption down to what we can catch from a very well-managed, sustainable fishery, and it's probably not a species that should ever really be farmed or ranched."
A documentary on the state of the bluefin tuna is scheduled to air at 7 and 10 p.m. July 21 on Current TV.