What killed Timothy Treadwell was a combination of his willful disregard of safety practices around brown bears  a violation of wildlife ethics  and his mindless moral values.  Treadwell quit using an electric fence while camping and refused to carry bear spray.  The fence would have eliminated the need for Treadwell to confront bears close to his camp, but he didn't want to "hurt" his "friends".  The end result was two dead bears and two dead people.  How moral is that?  There's a reason why campers and the Park Rangers who camp in Katmai use electric fences.  They work!  Not only that, it's a matter of wildlife ethics to use a fence to protect not only yourself, but the bears, too.