Summer Brings People And Bears Together. A Warming Climate Is Reshaping The Calendar

InnovationScienceSummer Brings People And Bears Together. A Warming Climate Is Reshaping The CalendarByJohn Drake,Contributor.Forbes contributors publish independent expert analyses and insights. John Drake is a professor at the University of Georgia. Follow AuthorJun 13, 2026, 08:14pm EDTBROOKS FALLS, ALASKA - AUGUST 12: A brown bear prepares to eat a sockeye salmon while fishing on August 12, 2023 at Brooks Falls, Alaska. The bears feast at the falls in large numbers between July and September, as millions of sockeye salmon swim upstream to spawn within the vast Katmai National Park and Preserve. Many of the same bears return to the falls annually, gorging on salmon to fatten up before hibernating for winter. (Photo by John Moore/Getty Images)Getty ImagesThe trailheads are full again. Across the mountain West and the Northeast, summer fills the backcountry with people, and it is prime season for crossing paths with a bear. Mostly, neither side is looking for the other. Two separate calendars, human recreation and bear biology, crowd into the same summer weeks, and a warming climate is changing when and why they meet.For a bear, summer is the run-up to hyperphagia, the late-season binge that lays down the fat it needs to survive winter. The hunger comes on a schedule. A bear’s appetite builds through the summer and peaks in the fall, when a big brown bear may eat almost around the clock and take in tens of thousands of calories a day. People arrive on the trails as that hunger climbs.More People, Longer Bear YearsTwo things bring them together more often. One is us. More people live near and move through bear country than a generation ago, and in wealthy countries the rare attack usually comes during something ordinary, a hike, a campsite, a walk with the dog. The other is the bears’ lengthening year. In one Alberta population, it was estimated that a four-degree-Celsius rise in spring temperature moved den emergence about ten days earlier. Warmth and access to hum...