Whale Balks at Bridge; Efforts to Herd It Back to Ocean Halted

A humpback whale, apparently agitated by efforts to drive it down the Sacramento River, refused Thursday to pass under a small bridge and leave the dead-end channel where it has lived for the last six days.

The effort to herd the 40-foot whale downstream with five boats was halted after two hours, when the giant creature ran into one of the bridge’s pilings as it thrashed around in Shag Slough’s shallow water.

“The animal looks very stressed. It doesn’t want to go through,” said rescue coordinator Bernard Krause, a volunteer from the California Marine Mammal Center, as he called off the attempt.

Although the whale passed under the bridge on its way upstream, it may be balking at going back, because there are remnants of old pilings and other underwater debris between the bridge supports, experts say.

Another Attempt Today

A local construction company was called in to clear the debris overnight, so another attempt to herd the whale through can begin today.

Marine biologists fear that the whale will die in the slough, which is about 15 feet deep and 100 yards wide, because of prolonged exposure to freshwater.

The 40-ton whale, which would normally be on its way to Hawaii at this time of year, entered San Francisco Bay 15 days ago and swam up the river to Shag Slough, about 60 miles from the Pacific Ocean.

On the assumption that the animal is in the river because it is lost and confused, 20 volunteers from the Marine Mammal Center sought to drive the whale out of the slough by banging on pipes suspended in the water from the five vessels.

The pipe-banging technique, known as “oikomi,” has been used in Japan to drive dolphins and smaller whales to slaughter.

The noise, somewhat like the sound of loud wind chimes, quickly drove the humpback--a baleen whale--down the mile-long slough to the bridge.

Once there, however, the whale swam in circles and figure eights, breathing heavily and lifting its pectoral fins out of the water as it turned in the channel.

At one point, the whale nearly beached itself on the east bank of the slough. Several times it lifted its head out of the murky water, apparently to get a better view of its surroundings.

The five boats, aligned in a semicircle, repeatedly backed off in hopes that the whale would find its way through beneath the bridge. Although the boats came within 10 yards of the whale at times, it made no attempt to attack the boats or go past them.

Underwater microphones picked up the sound of the whale using its navigational system of echo location--making noise that bounces back--in an apparent attempt to find an open passageway.

Finally, when the humpback ran into the piling, the rescue attempt was quickly halted. The animal appeared unhurt and swam back to the north end of the slough as the boats departed.

“We had success today in moving him,” said Mark Ferrari, a marine biologist who has observed the whale’s journey up the river. “Now we hope to have success tomorrow in moving him past Rio Vista.”

Sonar studies of the water under the bridge indicated that the debris leaves a clearance of no more than nine feet, not enough for the whale to swim over without scraping his belly. The space between the pilings is about 20 feet wide.

Scores of Reporters

Although the public was excluded from the scene, scores of reporters and photographers crowded the levee near the bridge to witness the unusual rescue attempt.

Crews from the California Conservation Corps on the bridge stood by to drop a plastic sheet into the water to block the opening if the whale passed through. Downstream, nine more boats, also equipped with pipes to clang, were prepared to join the herding effort if the whale cleared the bridge.

More than a week ago, the U.S. Coast Guard, the Marine Mammal Center and a group of psychics were successful in herding the whale about 12 miles downstream from nearby Cache Slough to the Rio Vista drawbridge.

However, the whale refused to cross under that bridge too and headed back upstream, ending up several days later in Shag Slough, above the narrow bridge passage.

The National Marine Fisheries Service, which is directing the rescue effort, said Wednesday that if the herding attempt fails, it is prepared as a last resort to hoist the whale into a water-filled barge and tow it to sea.

Several observers on Thursday, including state Sen. John Garamendi (D-Walnut Grove), who represents the district, speculated that the whale may have been drawn to Shag Slough by low-frequency transmissions from a nearby submarine communications facility operated by the U.S. Navy.

However, Capt. Kenneth Johnson of the Rough and Ready Island Naval Station, said he did not believe the transmitter, located on a 1,250-acre site near Dixon, was responsible.