I don't agree, quite to the contrary, I have testimonial vids and pictures from across the world, yes world, that predators and others will come into squeakers if the sound used is appropriate to the target, as well as not with sounds they have never heard
when used in an area that is or has been heavily called. Many without the use of scents or lures of any kind, from researchers trappers, and trail camera users who many don't even know how or where to attain any lures or scents.
Besides my own trials, and people who were instrumental in testing the units for a full season in different states and countries !
The major issue is that animals have to be able to hear the units, or in any unit made, and be in the range to hear them.
That's all end of story !
Why people can't get over using the animals ears, like they do the nose or eyes escapes me. Must be a mind game
that people can't get over, their ears are used just as much as the nose or eyes !
Some will continue to see this a mainly an advertisement, it is not meant that way, it is just simply education about using a different type of lure, SOUND !!
On a still night I turned on my e-caller and put on a rodent squeak sound. To my surprise coyotes came in even with it's low volume.
Sounds work. Watched it many of times with my thermal scope and scanner since then.
My Critter Collector squeakers now go with me when predator hunting and trapping.