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.
SPC, one of the things that makes the magnetic field theory hard to buy into for me is the extensive list of variables that can and do illicit the same exact response.
I don’t see how this theory could be singled out as the primary suspect amongst a lineup of known repeat offenders.
Then you have a host of conductive minerals called "Hot" rocks that will trip a metal detector just like a steel trap would.
If a coyote can indeed notice these magnetic fields, how could he isolate a handful of steel traps amongst thousands of acres of conductive mineral rocks ?
Now I understand there are places void of these conductive minerals as well. Maybe that is the caveat. It is certainly not the case here,
The area I trap is very rich in iron deposits. You cannot make a single sweep with the metal detector coil without it going off in most cases.
Maybe that along with dry conditions is why I don’t have any trouble.
Come to think of it I always thought the old theory that a coyote can detect the oxidation of the trap with his nose could be plausible.
Either way they are very interesting subjects that warrant more study.
I understand the variables could bring up questions. That's why for the most part I don't think it affects trappers to an extent be concerned with it. But I guess I'm not ready to discredit the fact that some animals can detect it. Maybe certain animals more than others.
I know a lot of Kirk's testing was probably geared more towards Beaver and he felt it really gave him the upper hand on those educated adult ones. Then when you're targeting animals with the use of cages, I would imagine it would generate a greater emf in that area.
Here's the forward to his book stating the testing that was done:
My findings based on infield testing, observation, real-time video, research periodicals, scientific studies, and reading trappers experiences with the devices mentioned. This work was done over 23 years trapping professionally. During this time, I experimented with body grip traps, round and standard, of various sizes. Snares and foothold traps were used of several sizes and snare lock types. Testing was done with experience from over 120 different cage trap designs, many having multiple sizes in length, width, and height, as well as trigger design. They were square, round, rectangle, triangle, and pyramid in shape. This included doors that locked with rings, powered and not. Traps with powered saloon-style doors on each end. Guillotine doors of various designs. Many had swing-down powered lock bar doors combined with some traps that had at least three different door designs on the same trap. Triggers on the cage traps used have been multiple numbers of pan designs to over six different wire trigger styles and type. Using trapping devices over 18,000 animals were caught, in the wild, and over 60,000 sets were made. During a 13 year period, of the 23 years, over 400 locations were set each year. More than one hundred thousand acres were accessed and over 14,000 animals were caught. In most of the 13 years, the bulk of trapping was done, in less than 120 days, with a 24hr check. 95% of the work that was done removing animals was Animal Damage Control. It wasn’t until a magnetometer was purchased that the way the animals were responding to set traps and hunting/ trapping devices made complete sense. For almost four years, I suspected, with very strong beliefs, but never could prove scientifically. I was always given doubt, from my findings, by respected professionals that I thought had the same experiences I had and the ability to interpret them. Concentrating on “the most effective traps”, the only thing they “all” had in common was a decrease in magnetic field intensity and a larger percentage of adult animals being caught in the traps with fewer refusals.
