I have read Kirk's book. I believe he has some very valid points. It has to do with EMF, Electromagnetic fields put off by metal. There are a lot of variables to consider though. The further north you go and the dryer the soil it's not going to transmit as much. Also, he found that better qualities of metal didn't put off a high field reading. So many may have not experienced many problems depending on where they live, soil conditions and the brand of trap, they used. He even stated it's a learned behavior not something they are born with. So, it's the older adult animals that would more than likely be the culprits.

I do believe animals can detect it and that may be the case as why some digging occurs with a trap bedded in front of a bait/lure test.

I have had very little issues with my sets being dug up. Most of the time it was a Grey fox or coon.I have had some uncovered slightly and reset and made a catch. Some of this I lay to my style of trapping in pre baited holes.I have had them work from a different angle after setting. If I have time I can adjust to him and catch him.