The first aquarium in North America with tunas on display now has another first: the only giant Bluefin tuna on exhibit outside Japan.
Two Pacific Bluefin tuna collected and brought to the Monterey Bay Aquarium in 1998 and 1999 now weigh in excess of 300 pounds—the benchmark at which they’re considered giants. They’re growing steadily; adding about 50 pounds a year, and could tip the scales at 1,000 pounds in just a few years. Eleven other Bluefins in the exhibit could become giants over the next three years.
The tunas and their smaller companions—including a number of 200-pound Yellowfin tuna—can be seen daily by visitors to the aquarium's million-gallon Outer Bay exhibit. They share the exhibit with the largest collection of open ocean animals in the world: the only oceanic Whitetip shark on exhibit anywhere; dolphin fish; black sea turtles; ocean sunfish; pelagic stingrays; California barracuda; and soupfin sharks.
Outside of the wild, it’s one of the few opportunities for people to see fish that have fascinated humanity for thousands of years and that are the basis of the world’s most lucrative commercial fishery. “It’s really been incredible to watch the Bluefins grow,†said Chuck Farwell, curator of pelagic fishes for the aquarium. “It’s rewarding to have them reach their full size.â€
Collectively, the Outer Bay animals consume more than 800 pounds of food a week, divided among four public feedings on Tuesdays, Thursdays, Saturdays and Sundays at 11 a.m. Aquarium visitors can watch the feedings, as can a worldwide audience via streaming web cam at www.montereybayaquarium.org
Though the fish haven’t been weighed, Farwell said their size can be calculated based on a predictable growth curve documented by aquarium staff and Stanford University scientists at the Tuna Research and Conservation Center (TRCC), a collaborative project between the two institutions.
Since 1994, the TRCC team has been tagging giant Bluefin tunas in the wild and studying tunas at the TRCC facility in Pacific Grove, next door to the aquarium. They are currently have computerized tags in 550 giant Atlantic Bluefin and 100 Pacific tuna. The devices collect data about tuna migrations across ocean basins, their internal body temperature and diving patterns. TRCC researchers have just embarked on a four-year effort to tag 1,000 Pacific Bluefin tuna as part of the larger Tagging of Pacific Pelagics (TOPP) initiative that will document the migrations of tunas, sharks, squid, albatross, whales and other open ocean species in the eastern Pacific.
Data coming back from the tags are helping shape management policies for Bluefin fisheries in the Atlantic, where tuna populations have plummeted since the 1970s because of increased fishing pressure. A single giant Atlantic Bluefin can sell for $100,000 or more in Japan.
“The ability to keep tunas in captivity has provided our team with an unprecedented ability to study these magnificent fish and pioneer new devices for following them in the ocean†said Dr. Barbara Block, a Stanford University professor and, with Farwell, co-director of the TRCC.