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Yosemite bears' rehabilitation seems to be a success

by Michael Mello
The Modesto Bee - January 16, 2003

For Yosemite National Park biologists, it's a good thing when their teenage wards run off and aren't heard from.

In the case of three young black bears, it means that they successfully have been weaned from human food and are sticking to the berries and acorns that constitute their natural diet.

The cubs were removed from the park, and put into "rehabilitation" more than a year ago when their mothers taught them to raid campsites and search for human food. The mothers had to be destroyed.

For months before their release into the wild, the bears lived at clinics in Idaho and Lake Tahoe where they had only minimal human contact and learned to eat a natural diet again.

Since then, they've made themselves scarce. Signals from radio transmitters that the bears wear have been hard for park biologists to pick up, and none of the bears has been spotted near a populated area since they were put in the wild.

No news is good news, Yosemite spokeswoman Deb Schweizer said.

"Bears we tend to hear about in this park are the ones in the parking lots, in the campgrounds," Schweizer said. "We tagged them, so we would know if they were doing any of these things. And they're not."

Bears are attracted to human snacks particularly sweets and scented items that campers often leave in tents or vehicles. Once they get a taste of it, they become "addicted" to human food, which is high in calories and sometimes easier to procure than berries. They often run afoul of humans, chasing them away or breaking into cars to get food.

Two of the bears, released early last year, have appeared to stick close to the Tuolumne Meadows area, near where they were released.

Signal readings from these bears have been scarce, leading biologists to believe that they are hibernating.

The other bear seems to keep to Bridalveil Creek near Glacier Point Road, where it was let go in 2001. However, it did take a field trip at one point, Schweizer said, roaming into Yosemite Valley.

"We all did hold our breath for a minute there, but that bear just went through the valley on his way looking for food elsewhere," Schweizer said.

While it seems the bears' rehabilitation was successful, "it would take a period of several years before we could be sure of that," Yosemite wildlife biologist Steve Thompson said.

"It's likely once a bear obtains human food, it would come back and check it out occasionally, especially if it's a bonanza of food in a car."

After declining for several years, bear incidents in the park spiked twice: once in spring, and during the Thanksgiving holiday, when bears broke into four cars in parking lots. It's possible those incidents were caused by a temporary lack of available natural food, Thompson said.

Since bear incidents peaked in 1998, when a record 1,584 occurred, Yosemite officials began an aggressive campaign to warn visitors about bear dangers. The recent break ins bring the year's total to 546, up from 231 last year.

"We had extraordinary success with our program last year, and I think people got a little lax this year and let down their guard," Thompson said.

When it comes to bear safety, Schweizer said, "People still need to realize that this is a change in habit long term. Information has indicated that our long term visitors aren't reading the information because they feel like they already know it. We feel like we have to reconnect with them."

Thompson stressed rehabilitation is a last resort. "The cub rehab is very expensive, it's labor intensive, and it's not the best outcome for the cubs. We're doing damage control by rehab."

Instead, people should prevent bears from getting human food in the first place, he said.

Added Schweizer: "We still haven't done our job until there isn't a car with food in it for a bear to break into."