ALASKA — After a string of warm summers, the Kenai Peninsula’s spruce bark beetles are now hitting their highest numbers since their last outbreak in the 1990s. “We’re seeing levels we haven’t seen for over a decade, since the late 90s,” said entomologist Matt Bowser of the Kenai National Wildlife Refuge. The U.S Forest Service and the Alaska Division of Forestry have run annual aerial surveys since the 1970s. This year’s survey found 405,000 acres of beetle damage — the most in a given year since 1997, according to Forest Health Program Manager Jason Moan of the Alaska Division of Forestry. About 95 percent of the statewide damage was in southcentral Alaska, Moan wrote in an email, with the majority in the Susitna Valley.