Nearly 20 years ago, there was a well-documented bear spray failure in Russia. A world-famous bear researcher, Vitaly Nikolayenko, was killed by a bear only two months after Timothy Treadwell and his girlfriend, Amie Huguenard were killed and partially consumed by a bear or bears in Alaska. Nikolayenko was half-eaten. All the bears involved were variations of the brown bear, also known as the European brown bear, grizzly bear, or Kodiak bear.Treadwell disdained any type of defensive weapon. Nikolayenko had bear spray and a flare gun. When Nikolayenko was late in reporting, a search team, including his long-time friend, Victor...