It's Safe To Get Back Into The Water!
It's official, all sharks have left the south of market area, unless of course you include anyone in a leisure suit at The View Lounge at the 4th St. Marriott.
Three black-tipped reef sharks swam all the way from the South of Market to Golden Gate Park on Wednesday, joining a flurry of fish and a regiment of rays at the new California Academy of Sciences.
In tubs and tanks and by truck - and swimming all the time- they covered 5.4 miles to reach their permanent home.
For Bart Shepherd, curator of the Steinhart Aquarium, and Freeland Dunker, the academy's veterinarian, it was a journey that began in tension and ended in relief two-and-a-half hours later.
The sharks are tender creatures, and moving them from their temporary downtown home on Howard Street took four fast and delicate transfers, one shark at a time:
From their 20-foot-wide, ground floor circular tank, where they've been living for a year and a half, into a 40-gallon water-filled tub for a move to the street; then into a 300-gallon, truck-borne water tank for the swimming trip to the park; and finally into another mobile tub for a watery ride on a freight elevator to their final destination - a sandy reef-bordered tank inside the new academy building, where rays and fish live too.
On a daily basis now, the academy is moving everything living, pickled, pinned or stuffed to its new museum, which is scheduled to open Sept. 29.
The academy's 10 rays moved in on Tuesday, and Diego, the 80-pound sea turtle, arrives Friday. The first trees of the towering tropical rain forest were planted in December, and they're already flourishing. The living roof of the building is green with plants and home to birds, bees and butterflies. The Planetarium dome is ready for its star machine, and the African Hall's dioramas are being painted. But moving the black-tipped reef sharks (Carcharhinus melanopterus) was perhaps the most complex move so far.
Near the end, Shepherd - garbed in wetsuit, mask and snorkel - had to baby the last of the three female sharks along in her big new home until she was finally able to cope with the varied water changes in salinity, acidity and oxygen level she had encountered during her morning-long adventure. Her two companions had stayed frisky all the way.
"It's always a time of tension when you have to move fish," Shepherd said, "and it's a huge relief when it's over."
The third female, nearly 3 feet long like the other two, was visibly tired and even a little sleepy from hyperoxygenation and was almost motionless after Shepherd's crew of assistants moved her into the large sandy-bottomed reef tank.
Tenderly then, Shepherd eased her along through the water with his gloved hands and moved her tail back and forth to simulate her natural swimming motion and bring her blood pressure back toward normal.
With her pectoral fins spread wide, she seemed to let Shepherd half-guide her until, after half an hour, she exploded out of his hands with her tail thrashing furiously. She swam swiftly off to join the other two across the broad lagoon, where they'll live from now on - immediately next to the academy's huge living reef of Philippine corals.
"I wasn't too worried," Shepherd said later, "because she was breathing really well and her eyes were open all the time. But then, you always worry at least a little. Things can get tense."
Dunker, the vet, had his hands full, too. Before the sharks left Howard Street, he and his high-tech assistants had to weigh and measure each one and during the course of the trip, they monitored the salinity of the water carefully. On Howard Street, the salt water was chemically made; in their new home, the water comes directly by underground pipe from the Pacific Ocean just off Ocean Beach.
The vet staff also kept records on the water's oxygen levels and acidity during each transfer, and before the work started drew 2 milliliter blood samples from each shark - to test in the lab for stress levels and to freeze for future research.
The staff also carefully spotted each shark's left pectoral fin with silver nitrate to identify it as female, and each had already been tagged with a computer chip to follow its health as it grows -eventually, perhaps, to as much as 6 feet.
It was as scientific as you get when you're moving fish around, and no one got a shark bite, Dunker said.
The new home for the sharks also holds a dozen or so rays of several species, who swooped after the first shark as if she were an interloper, but soon tired of the chase.
There was also a welcoming committee of small Pacific tarpon (Megalops cyprinoids), a bunch of butterfly fish (Heniochus acuminatus) and many moonyfishes or monos (Monodactylus argenteus). None of them seemed to care about their new lagoon mates, and although the sharks hadn't been fed for two days and won't be fed again for another day or so, they paid no attention to their company.
"But they're predators," Shepherd said, "and when they do begin to be hungry, the fish will have found plenty of hiding places in the reef rocks around them."
E-mail David Perlman at dperlman@sfchronicle.com.
