All that I will add to this discussion is that I hope that the imminent Man-made Global Warming and Climate Change doesn't negate all of the authors findings.
That would crush book sales...

I would think that if it were not an audio books or video the average trapper would make page 3 or less before going into a coma. That is unless you have lots of pictures. Just sounds a little dry for me.

How do you know it helps you catch older animals, did you age them all?

If a animal grows up around fences, culverts and roads it is natural to them they don't have human intelligence to comprehend where they come from .

If by human intelligence you are referring to self-awareness or realization of their place in the world, then that's another thread. I was taught that every animal species is neither dumb nor smart....instead they are perfectly adapted to the lives they need to live. I think it is an error to think that animals would interpret the world the way we do. Their senses far surpass ours.

I'm not sure how to re-write my post any differently. The point is that they sense it as being foreign, not always dangerous, but foreign. Something that stands out in the natural environment.

I guess for me, the concept that animals can sense a field around metal objects seems pretty realistic. I think it would be harder to believe that they are limited to processing the world the way humans do.

for·eign
/ˈfôrən/
adjective
1.
of, from, in, or characteristic of a country or language other than one's own.
"a foreign language"
(2.)
((((((strange and unfamiliar.))))))
"I suppose this all feels pretty foreign to you"

If something has been there for the hole life of an animal or in most cases several generations of animals ancestors it cannot be by definition foreign

I believe that IF an animal reacts negatively to a magnetic field it is learned by some negative experience that animal has. A trap pinching or going off in its face (beaver and killers) And most of those would be older animals. Older is anything over a year as most animals die with in the first 1.5 years of age when mortality rates are 40 to 60%. Again I am trying to prove Kirk correct, simply because if I try to prove it right, then I know yes or no based on facts, not bias. Why? Because it will answer why I get some animals that just for no apparent reason will not enter a cage trap. Most times I can see the reason, and most times it is an animal that has been caught and released somewhere else or where a young animal has been rehabbed and turned loose. These animals just plain are cage shy or cage smart. CAGE SHY they flat take off, CAGE SMART they work the cage from the side never going in or going into the trap up to the pan and not going any further. One of the tricks of many I use on smart animals working the outside is simply Flip the trap around 180 degrees so the open door is where the back was. Most times the animal is caught the next time they come to the trap. working on behavior rather than methods. ( working damage gives me the advantage of seeing what one animal is doing, where fur trapping I see many and can't tell what each one is doing) Every trap I have tested has had high readings, so in theory by flipping the trap around and the field is the issue, then the same behavior should be seen just on the other side. So I believe that on cage smart animals the field is not the issue. With that being said, I still have to answer the TRAP SHY question, why do a few animals take off as soon as the trap is set there set or closed????? or why do they eat the little bean size baits outside the trap yet never enter the trap?????? Up until now, I have always believed it is catch and release and still believe it as a rule. But maybe just maybe on some, it could be the field. I do a lot of beaver control work, why do most beaver go right into that killer, yet that one beaver sprung the trap? Does chance or hesitation cause the miss????? If hesitation why did it hesitate when the rest didn't????? I know and I agree that when I am fur trapping I am thinking too much and yes when I am fur trapping that is my time to get away from the stress and pressures of my business. So who cares, leave for seed. But in my business, IF I CANT CATCH THAT CRITTER OR MAKE IT LEAVE I don't get paid and MRS Jones reminds me the bills have to be paid LOL

I am also going to do some testing with buried springs for the coyotes and fox. (I can't possess foot traps in NJ or I would use a welded open trap) Springs seem to have a high reading, so these springs or any metal that has a higher reading than the surrounding area placed in front of a dirt hole or flat set should give me the same as a trap.

I am supposed to be giving a cage trap demo at the PA. convention this June if it is still going to happen. And if I find positive to this theory then I will give Kirk a node, if I am still in the air I won't say anything. I do believe in some situations he may be on to something, but also there are many reasons why animals react negatively and the better we are as trappers and outdoorsmen the more we realize this.

On a side note, I bury DP traps in pockets and dirt holes in my advanced DP systems. I find that just sticking the trap in the ground the standard way (KISS) the fox and coyotes tend not to work at getting the meat or bait out of the trap when exposed (KISS) yet when I bury in a bank or ground they dig the same trap out and try to get the bait out. Just something to think about. By the way, Bob Noonan asked me if I stay up all night thinking about this stuff LOL I laughed and said no just all day every day LOL

Sorry for the book but I needed a reason not to go out in the rain and check jobs yet so I wasted time here LOL

When It comes to dirt sets I believe that the animal Is SET shy not TRAP shy.

MnCedar has summed up my thoughts and opinion fairly well. There is no doubt regarding some animals abilities under certain circumstances to avoid and sense certain things that may be seen and unseen. Whether it is thru smell and or a magnetic field detection of an object. These circumstances do occur and I have seen it in varying degrees over the years.

For as long as I have been trapping I have seen and experienced my share of situations. For the most part there aren't many animals that cant be caught one way or another in time. Being an intelligent species as we are that gives us the ability to over come most any circumstance we are presented with in time. It becomes a situation that we learn from when we do succeed.

That's what makes trapping so rewarding for those of us that have been at it for the long haul.

If it was all so easy most would loose interest pretty quick I would reason. It presents constant challenges and keeps us thinking as to how we can improve our skills.

I have found several ways in dealing with what I perceived is an animal smelling or detecting my trap at a particular set or location. It definitely was smelling or sensing something it couldn't see since the trap was buried in most cases.

One situation was remedied by grating a piece of dry cow dung chip over the set area which in my mind disrupted its ability to determine the exact position of the bedded trap. In a couple days I had caught the fox doing the frequent digging at the set. I never had a problem in the area again with diggers. I have caught many fox in that pasture over the years. Red and Grey fox.

After that experience I have always carried a bucket of shredded dry cow chips for blending into my set dirt at times to give me what I had learned was a valuable tool to use when I felt it was needed.

The next situation was another fox set sitting in a harvested corn field with some still standing corn in an area that was somehow missed during the harvest. These types of locations provided interest for hunting fox so they always got a couple sets back in those days. Had one trap that was set off every few days and some bait pulled out of the hole and wasn't sure what was firing it.

I hadn't caught anything there for a while and it had been very wet and rainy during this time frame. I couldn't see the set from the road due to the standing corn which is why I chose the location. I didn't carry any equipment or dirt into the location for this check. Once again the trap was fired and the bait pulled out.

I did reset the trap back as best I could under the muddy conditions and it certainly wasn't what I would call a good finished set. With no dry dirt, only mud and clay chunks lying around I pondered what to cover the trap with. I looked around and found a few leaves blown in the area of the set and found some weedy grass growing sparsely close by and pulled it up for trap cover.

I torn the grass and leaves apart and blended the trap as best I could with the cover available. Not having high expectations for this set I returned the next day to find a grey fox jumping at that set. Who would have figured that would produce. A set made like a first time trapper had set it.

The trap was somewhat visible after my feeble attempt to cover it but it was left as good enough.

I will continue to catch animals with the equipment I have and make the adjustments as needed to continue to be successful.

Understanding animal behavior and using the many tools that we have will give us many options to match wits with the most seasoned animals out there.

Interesting information has been discussed and somewhat evaluated now it is up to each of us to decide how and if it will be utilized in a productive manner along the way.

Thank you for the book response Jonesie.
Maybe my wording is not correct but the cage trap should have a negative reading or a lower reading all the way through the trap No matter which end he enters.As the animal looks in the trap it should be the same all the way through as far as being below the induction of the earth where you’re at. Turning the trap around might help but Would depend on the ability of the predator.You need to have a low reading no matter which end you stick the magnetometer in the trap.
The reading of the induction being lower should extend from one end of the trap to the other, inside.

Jonesie
A spring would create high intensity but would not have the surface area of a trap to disrupt the Molecular structure around it. Increasing the smell.

Waded through most of this thread, and trying to get my head around this magnetic field. The thing that popped into my head.......is this similar to the magnetic field that is generated by things like underground utilities and such? Things that can be detected by "witching"? That also may seem like voodoo until you have done it and prove to yourself it works.

Are you saying these traps generate a similar field that the animals can detect just like a person using witching rods can?

Divinity rods I have used many times in years past to find well water, gas and water lines etc It does work so is it our bodies that cause the rods to work at detecting the fields or is it our bodies transcending the energy down into the rods creating the response?

I learned in years past to keep a couple pair of rods made from old bent coat hangers as my rods. They seem to be in my experience more consistent in their reading and they flow/rotate easily in my hands as they react to the magnetic fields as it is detected.

I also believe the metal of the coat hanger rods serves as a better conductor of the energy in a stronger manner for detection. Never used the wooden sticks much once I got good with the metal rods.

From what I have seen I'm certain that coyotes get location shy when they see another that's caught and are in distress.
I think you can place the exact same set some distance away and start making catches again. I think other animals react the same way.

I thought the same for many years. Then I tested as explained in the previous threads several times.

You’re right it does exist. It’s just another way to determine what you need to do and to eliminate more questions.

Jonesy,
You can't even possess footholds in NJ? So if you wanted to go out of state and use them you would have to store them across the state line? Yet you write about using DP's which also hold the foot. Those are some weird laws.

So drags and long chain? Would that increase magnetic field and disrupt potential catch?

I'm 15 sets into my testing of whether coyotes can detect a trap in front of a dirt hole so far and the reactions are VERY interesting. I'll share my findings after 30 sets. What I see goes in the face of some of my theories and some theories others have. I will say at this point it seems most likely the majority of the coyotes can detect a clean trap is in front of a hole. Actually has been the most interesting thing I've playing with coyotes. Remember theories are only theories until they are tested, unfortunately if theories get repeated enough people start thinking they are facts.

Food for thought
Witching water and pipelines works to differing degrees for some people. Ive seen it first myself. Some people the signal is real strong and the same pipeline can't be detected at all by another person using the same method.