I was told by a prominent guide long ago that salmon & steelhead are often bothered by stronger sonar waves emitting from fish finders: particularly in shallower areas of rivers & bays. That made sense to me and ever since I have used my Fish Finder sparingly and on low power. Now, just this afternoon, I read in Field & Stream about a small study where divers observed fish behavior under varying strengths of sonar signals. They first noticed that the sonar was audible to them as "pinging" sound. So they figured that the more sensative fish's lateral lines would pick it up stronger. And indeed, they observed that under more intense FF sonar waves that many fish would be bothered to move a distance away. So this now confirms to me that my suspicion of multiple sonar emittions coming from a number of boats in areas of heavy usage, such as at the mouth of the Wind R. is one of the factors that cause the bite to just shuts off many times. Of course there are other factors for that, but they are mostly out of our control. There are also exceptions to this syndrome; such as the bumperboat meat hole by the N. F. Lewis hatchery where many boats cram over stacked up springers in 30' to 40' of water. For fishing sal./steel. in 5' to 20' feet of water I think that FF's more often function as a depth sounder than a true fish locator. In the shallower areas of rivers most fish tend to swim around the noise of the OB motor and FF, rather than swim right under the narrow band of the transducer anyway. So I would like to get some feedback opinions here as to what you think dozens of FF's buzzing the fish in an otherwise productive area does to affect the bite. And what can be done about it? I don't think anyone cares to stand up to yell thru a bullhorn for everyone to shut off their FF's instead of just leave them on. Media education of anglers? - Steve

[This message has been edited by Reel Truth (edited 05-16-2000).]