Sprawl or happenstance could be why bears mauled seven people since Thursday, including a 12-year-old Michigan girl who played dead to survive, experts said. Wildlife officials were conducting tests on a bear they killed to determine if it was the same one that mauled Abby Wetherell of Cadillac, Mich., Thursday as she was jogging, CNN reported. Authorities also reported attacks in Colorado, Wyoming, Idaho and Alaska, where a hunter survived for 36 hours in the remote wilderness after he was attacked. Tom Stalf, chief executive officer at the Columbus Zoo in Ohio, suggested the increased attacks could be because vacationers are invading the bears\' living areas. \"The reason why we\'re having bear attacks now is because we have vacationers out in the areas where bears live,\" Stalf told CNN. \"They\'re out foraging and looking for food.\" Stalf said the migration of humans is another reason for more bear encounters. \"It\'s called urban sprawl,\" he said. \"As we vacation and we move out of the cities and into the country, we\'re going to cross paths with different types of animals.\" Harry Reynolds, vice president of the International Association for Bear Research and Management, suggested sometimes it\'s just circumstantial luck, CNN said. \"I think the recent attacks are circumstance and not any larger outside issue weighing into the attacks,\" he said. \"In past years in Alaska, when there are berry failures, the bears may be more aggressive in looking for food. But this year was a good crop. I really think the recent bear attacks are just circumstance -- people in the wrong time at the wrong place.\"