[MARINE_BIOLOGY_INTERNATIONAL] Ploys fail to drive Gray Whale to ocean

 

Eureka, CA - Scientists have herded it with boats, used noisemakers to frighten it and piped the sound of its main predator (Killer Whales) under water, but the 45-foot-long gray whale that has been in the Klamath River for four weeks refuses to budge.

After the latest attempt to get the whale to leave the river failed, scientists are taking a wait-and-see approach to the situation, said Sarah Wilkin, stranding coordinator with the National Oceanic and Atmospheric Association. They will continue to monitor the whale, and attempts to intervene have been stopped, she said.

"We'll just kind of take it day by day," Wilkin said.

Since the whale swam upstream with her calf June 28, she has been hanging out underneath the Highway 101 bridge, creating a spectacle for motorists along the highway.

For the most part, scientists with NOAA and Humboldt State University and officials with the Yurok Tribe have just kept an eye on the whale and her calf. But on Sunday, after people had spotted the calf just outside the river mouth, scientists from both organizations as well as the Del Norte County Sheriff's Office used power boats, kayaks and noisemakers to get the adult back to the ocean. That attempt failed.

On Tuesday, scientists played recordings of killer whales and man-made alarm sounds under the water, Wilkin said. Initially that appeared to work, she said. The animal turned around and traveled downstream. But after awhile, the whale turned around and headed
back underneath the U.S. Highway 101 bridge, Wilkin said.

"It didn't have the full result we were hoping for of having her go all the way out of the river," she said.

Wilkin said the whale does not appear to be skinny or emaciated, but she thinks the whale hasn't been getting very much to eat.

HSU marine biology professor Dawn Goley said the condition of the whale is typical for those who have just stopped nursing their calves. The calf had last been seen by one of Goley's students at the river mouth Saturday. Wilkin estimated the calf's age to be between five and seven months old, which is usually when they become independent.

"In the days before it left, it started spending time away from the mom and it seemed like that time was increasing up until the point where it just left entirely," she said. "Once weaning is done, the moms and calves don't hang out socially."

Even though scientists aren't too concerned about the whale's current health, Goley said they are concerned about the river depth. They're also worried about tension between the whale and people on the riverbank.

According to Thomas O'Rourke, chairman of the Yurok Tribe, tribal officials have discussed how the whale's presence will affect the fall commercial salmon fishery, which begins Aug. 21. There will also be an abundance of sport fishermen on the river, he said. The commercial fishery is about two miles downstream from the U.S. Highway 101 bridge, where the whale is, but once she moves downstream she'll have to pass through a congested area of nets, he said.

"If the whale decides it wants to go out, basically what we'll do is have an emergency shutdown of the river," O'Rourke said. "We have tried to usher it out, we've tried to spook it out and we've tried to get it to turn around and go out, but have been unsuccessful."

This isn't the first time a whale decided to take a detour into fresh water. In 2007 two humpback whales, Delta and Dawn, swam 90 miles up the Sacramento River. According to Wilkin, Delta and Dawn swam much farther upstream and there were serious concerns about the humpback whales' health. O'Rourke said the last time a whale swam up the Klamath River was in 1989. It left the river without incident.

Scientists are still unsure why the two whales swam up the Klamath River instead of continuing on to their feeding grounds in Alaska, but O'Rourke said there must be a reason.

"Things in our world don't happen without a reason, without a purpose," he said. "The whales coming here, they carry a message, and they will stay here until the message is received, whatever that may be."

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