From today's AP news:

For the last 16 years, park rangers have done their best to warn visitors about the perils of leaving food in their cars, which a bear can easily peel open for a quick treat. And now a bear management team has begun outfitting bears with sophisticated GPS tracking collars to better understand their movements.

Overall, reported bear encounters have plunged by 92 percent since 1998, when the park embarked on a concerted public education campaign.

Despite their long-term progress, park rangers have lost ground in the battle this year.

Full story at:
http://news.yahoo.com/yosemite-rangers-try-keep-hungry-bears-bay-201022418.html