Whale Rescuers to Give It a Rest

May 24, 02:50 PM

Current Headlines: By Ramon Coronado, Christina Jewett, The Sacramento Bee, Calif.

May 24--Gently herding the whales with a flotilla of friendly boats didn't work. Nor did banging on pipes or playing scary recordings. So Thursday, whale rescuers are taking a break.

"We are not going to do anything," said Jim Milbury one of small team of whale rescuers.

Early Thursday the humpbacks were spotted a mile north of the Rio Vista Bridge, Milbury said.

Whale rescuers will be monitoring the whales and taking photos of their wounds to compare with previously taken pictures to see how badly their wounds have deteriorated, Milbury said.

With the extended Memorial Day weekend approaching, Millbury said the Coast Guard and whale rescuers would be enforcing the 500 feet stay away zone. Boaters are urged to keep tuned to emergency broadcast channels from the Coast Guard.

Late Wednesday, rescue teams had introduced a recording of killer whales into the water near Rio Vista, hoping the ominous sound would push a pair of wayward humpback whales toward the ocean.

The recording, of orcas preying on a gray whale mother and calf, replaced an unsuccessful pipe-clanging strategy that was followed Wednesday by gentler sounds of humpbacks feeding. The ailing mother humpback whale and her calf had frustrated those attempts by repeatedly swimming upriver and even under a noisy tug.

The killer whale sounds were played until sundown Wednesday.

The orca recording carries its own risks, but its use underscores the rescue effort's growing urgency.

In the worst case, killer whale sounds could frighten the mother into deserting her calf, or could scare both whales into stranding themselves in shallow water, said Scott Hill, a population ecologist with the National Oceanic and Atmospheric Administration.

Yet with the whales' condition worsening and the pipe-clanging clearly ineffective, "we feel it is important to get these animals to at least a brackish environment in the near future," Hill said Wednesday. "We don't know how long a whale will last in fresh water."

Hill said that Humphrey, the last humpback known to linger in the Sacramento-San Joaquin Delta, spent some of his time in brackish areas where fresh water mingled with salty, and yet he still suffered skin damage.

After at least 10 days in fresh water, these whales -- named Delta and Dawn -- are beginning to peel.

That's weakening the barrier that protects them from bacteria, said Trevor Spradlin, a marine mammal biologist with NOAA's National Marine Fisheries Service.

For much of Wednesday, scientists made essentially no progress.

The whales first edged nearer to Rio Vista, then turned tail and swam back toward Sacramento.

The misfires illustrate what biologists and veterinarians have been saying all along -- that everything they try in the race to save the two whales is an experiment. No one can say how it will end.

"We're not losing hope. No one has lost hope," said Jim Oswald of the Sausalito-based Marine Mammal Center. "At the end of the day, it's up to the animals."

The animals continued to draw crowds, among them Mike and Denell Towns of Brentwood, who stood on the banks of the Deep Water Ship Channel north of Rio Vista late Wednesday morning, watching as the whales surfaced and disappeared.

"It makes you wonder, is it wiser for them to help her, or is it part of natural life for her to figure it out?" Denell Towns said.

Her husband had a radio tuned to the rescuers' channel clipped to his waistband, so the Townses and their two daughters could hear barked commands like "start banging" just before the din escalated.

Yet even as clangs from whale-driving boats reached the shore, the family saw all 12 boats turn north again in a tightly coordinated flotilla, following the whales.

"She's just playing with them," Denell Towns said of the mother whale.

As rescue efforts continued, university and federal labs awaited tissue samples that could provide answers about the whales' ancestry and their health, as well as the less pressing question of whether the calf is male or female.

The samples, plucked from the mother whale by a crossbow dart on Monday and shipped off by overnight express service Wednesday, will be analyzed by three different labs, according to the National Oceanic and Atmospheric Administration's National Marine Fisheries Service.

Researchers at Oregon State University and the University of Tennessee at Knoxville said analyses, which could take from four days to a week, might provide more clues about how much danger the animals are in.

The best answers always come from people on the scene, "describing what they can see with their eyes," said Dave Rotstein, a professor at the University of Tennessee College of Veterinary Medicine and a pathologist for NOAA's Center for Marine Animal Health.

"The skin is kind of like the window to the animal. When the skin condition goes from being smooth to discolored or pitted or open wounds ... that's not considered a good sign," Rotstein said.

Yet tissue samples can also be revealing, helping scientists discern how well the whales have eaten, what they've eaten recently, what sorts of bacteria or fungus are in their skin, whether any infections are local or widespread, and where the mother whale normally roams.

By Ramon Coronado, Christina Jewett and Carrie Peyton Dahlberg

-----

To see more of The Sacramento Bee, or to subscribe to the newspaper, go to http://www.sacbee.com.

Copyright (c) 2007, The Sacramento Bee, Calif.

Distributed by McClatchy-Tribune Information Services.

For reprints, email tmsreprints@permissionsgroup.com, call 800-374-7985 or 847-635-6550, send a fax to 847-635-6968, or write to The Permissions Group Inc., 1247 Milwaukee Ave., Suite 303, Glenview, IL 60025, USA.