(AP) — Rangers at Yosemite National Park are in a constant battle to keep wild black bears — with their ultra-keen noses and powerful paws and jaws — far away from humans. Overall, reported bear encounters have plunged by 92 percent since 1998, when the park embarked on a concerted public education campaign. Throughout California their population is at about 30,000, and they are increasingly wandering into cities, such as Bakersfield, Monterey and San Luis Obispo, said Marc Kenyon, a senior environmental scientist with the California Department of Fish and Wildlife. The incidents of destruction peaked by the 1990s when images of bears roaming campgrounds in search of a meal made national news, prompting the current campaign, which has paid off. The park recently began fitting Yosemite's bears with modern GPS collars to learn more about their feeding, mating and general activities — and to keep track of them. The new technology replaces outdated radio collars, allowing rangers to monitor bears as they travel into the park's remote backcountry.