| The Magazine of the CALIFORNIA ACADEMY OF SCIENCES |
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HERE AT THE ACADEMY Testing The Downtown Waters
Two guys carrying a cooler full of fish isn’t unusual. Two guys carrying a cooler and releasing a live, 18-inch-long catfish from it seems like a contradiction of fishing logic. But these fellows aren’t lamenting the one that got away; they’re aquatic biologists bringing this charcoal gray, polka-dotted Synodontis longirostris to its new home. The long-nosed catfish, along with buckets full of red hook silver dollars and other tank mates, are among the first to brave the waters of the Academy’s new downtown location at 875 Howard Street. Though their cross-town journey in a rental truck from Golden Gate Park spanned a mere four-and-a-half miles, the path leading there has involved years of planning and lots of people, and sweat. Eighteen months ago, Steinhart Aquarium staff started deciding what critters could be housed at the modest, 26,000-square-foot downtown museum. Species difficult to replace because they are threatened, endangered, or possess a historical value to the collection scored the highest. The temporary facility’s largest tanks were custom-designed for aristocrats such as the alligator gar, Australian lungfish, and arapaima. Smaller tanks, many from the park, were added to create more holding space and variety. Thousands of animals made the cut, and 85 percent of the Aquarium’s species will be represented in the 133 tanks downtown. Creatures not chosen because of space constraints or other issues were sent to adoptive homes. Since last September, the Aquarium has moved these animals to organizations around the country. Finding good homes hasn’t been easy. Steinhart superintendent and general curator Tom Tucker considers the adoption program one of the biggest challenges of the move downtown. Because of their maturity, the Swamp’s two 17-year-old American alligators proved difficult to place, until Chehaw Wild Animal Park in Georgia finally accepted them. Last January staff sent the lounging pair off in style with a party complete with gummi gators and gator-inspired poetry. Placing the Academy’s three pelagic stringrays was easy. But shipping them to Maryland during the chill of winter would have been tough on the fish, which would have required temperature control during transfers between flights. The Monterey Bay Aquarium came to the Academy’s aid and generously granted holding space until the rays could travel. The Aquarium staff has juggled a mountain of logistics, simultaneously curing tanks, planning for coral grow lights, finding adoptive fish parents, and caring for an old and crumbling aquarium in Golden Gate Park. The race to complete the new museum by opening day has kept them, as well as teams of designers, plumbers, and fiberglass experts tackling new tasks the moment others are finished. First among the slew of concerns about getting the new system up and running is obtaining water—no small task with such a large aquarium. Freshwater tanks get ordinary tap water. In theory this should be simple; however, San Francisco’s recent switch from chlorine to chloramine as a disinfectant has complicated the usual treatment process. Both chemicals are lethal to fish, frogs, and reptiles. But while chlorine dissipates over a few days, chloramine must be removed chemically by additives and mechanically by filters. Saltwater presents an even bigger challenge. For decades the Aquarium has simply piped in 80 gallons of seawater a minute directly from Ocean Beach. At Howard Street, 2,000 gallons of water has to be trucked in each week. Once water is in a tank, it has to be conditioned. The chemistry and temperature must be right, drainage ensured, and protective netting installed. When everything is set, the tank must run for a week to make sure the system is stable. Only then can the fish be added...slowly. The filters use “bioballs,” plastic spheres coated with several species of bacteria to clean the water. They start kicking in only after the fish have been introduced and their respiration and waste products generate ammonia. One species of bacterium on the bioball converts ammonia to nitrite and another converts nitrite to nitrate. Ammonia is potentially deadly to fish, while nitrate is nontoxic if kept at low levels. Once the process gets going, the bacteria reproduce and form colonies capable of handling higher concentrations of ammonia, which means more fish can be put into the tank. “Your filters are as much a living part of your aquarium as the fish themselves,” Steinhart assistant curator Ken Howell explains, “so you can’t just take a lot of animals and throw them into a tank.” Hearty fish such as the polka-dotted Synodontis, which can withstand large water-chemistry fluctuations, are tank pioneers, helping to stabilize the water for more sensitive species. But ongoing construction complicates the process. “Everybody is a little bit spoiled with Steinhart. It has been running for so many years, it’s a very stable environment,” Howell says. “I could drain a tank in Steinhart and fill it up and put fish in it within a day. Here we’re dealing with new fiberglass, toxic resins, and all sorts of industrial materials, so everything has to be very, very clean.” “It’s difficult to predict how animals will act when their surroundings are altered, their tank mates are changed, and they are crowded,” says curator Tucker. Tucker, Howell, and the rest of the Aquarium folks will be on red alert for problems in the months to come. Then they should be able to go back to contending with the usual day-to-day stuff—at least until the Academy returns to Golden Gate Park in a few years. But that’s a fish story for another time.
Anna Barr is Youth and Adult Courses Coordinator at the California Academy of Sciences. |
