Q: I think a small boat horn would be as effective in dealing with bears as would say bear spray, also
it could be used if you get lost to call for help, and it also can be used to a limited degree to defend
yourself. I'm not sure but I believe Alaskan salmon fisherman use them for protection against you (bears). —James McCandless, via email
A: Believe it or not, in some studies boat horns have shown that they can be effective deterrents to me and my kin. I'm not a fan of loud, unfamiliar noises of any kind, so loud, gas-powered boat horns can pack an especially powerful aural punch to my sensitive ears.
In an informal study undertaken by Alaska Fish and Game officials and recorded by noted bear expert Stephen Herrero in his excellent Bear Attacks: Their Causes and Avoidance, grad students monitoring salmon populations took gas-powered boat horns with them into the Alaska backcountry and let loose occasional blasts, especially when they were surrounded by dense brush. They never once even saw a bear, despite encountering loads of bear sign. But when they decided they'd like to see me after all, they stopped using their horns, and they immediately began running into me along the stream.
As far as a deterrent in an encounter, there isn't enough data to compare directly to bear spray. But extremely loud and sharp noises like boat horns seem to be among the most promising ways to both scare me away from you and associate humans with painful, obnoxious noises. They seem to be especially useful near large rivers, where I won't hear the usual deterrent sounds (clapping, singing, loud voices).
There are some caveats to the boat horn: If you hike through the backcountry constantly tooting it to scare me off, I might run away, but I'll bet any hikers trying to enjoy the view won't. They'll probably try and find you, and they'll likely be angrier than any bear you'd ever encounter.
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