Fred Mills. said:

A Canadian writer, Farley Mowat, in experimenting with wolves up North, claimed he "Marked" his territory by "Pissing" around his tent, and it worked. He claimed that the wolves never bothered him after doing so.

  You could try this, but I recommend doing it after dark, so prudish neighbours won't see you and complain.

My Scoutmaster started me doing that when I was 11.  I taught my Scouts the same thing.

Fred Mills. said:

A Canadian writer, Farley Mowat, in experimenting with wolves up North, claimed he "Marked" his territory by "Pissing" around his tent, and it worked. He claimed that the wolves never bothered him after doing so.

  You could try this, but I recommend doing it after dark, so prudish neighbours won't see you and complain.

My Scoutmaster started me doing that when I was 11.  I taught my Scouts the same thing.

Fred Mills. said:

A Canadian writer, Farley Mowat, in experimenting with wolves up North, claimed he "Marked" his territory by "Pissing" around his tent, and it worked. He claimed that the wolves never bothered him after doing so.

  You could try this, but I recommend doing it after dark, so prudish neighbours won't see you and complain.

Hey!  I do that (outer perimeter) to help keep deer away from the vegetable garden.  Not sure how effective it is though as I also employ a few other methods (Scarecrow, blinking leds and miloganite) but the deer aren't eating my food even though I am surrounded by management area and there is no fence.

Fred Mills. said:

A Canadian writer, Farley Mowat, in experimenting with wolves up North, claimed he "Marked" his territory by "Pissing" around his tent, and it worked. He claimed that the wolves never bothered him after doing so.

  You could try this, but I recommend doing it after dark, so prudish neighbours won't see you and complain.

     Oh my freaking God, Fred, I don't know if you have this thing called Nextdoor up there in Canada, but for those of you who do: can you imagine the outrage on Nextdoor? Everybody with videos on their ringdoors and motion activated security videos and whatnot. The righteous indignation would be good for about 700 incensed responses.

 edit...that would be spelled Canada

A Canadian writer, Farley Mowat, in experimenting with wolves up North, claimed he "Marked" his territory by "Pissing" around his tent, and it worked. He claimed that the wolves never bothered him after doing so.

  You could try this, but I recommend doing it after dark, so prudish neighbours won't see you and complain.

Secret weapon, available at Ace Hdwr.

To keep large peccaries Javalina pig like creatures that can get up to #300 out.

I sprinkle granulated Coyote Piss where they used to go under my house, hasn't been a problem this year....

Predator  Urine, Oh Boy!

I guess I got lucky with my little cat. No poop and all my fish are still alive and swimming.

ROFL, that sounds like something I would do.

David Maynard said:

 

Randy had an issue with a cat defecating in his ballast....essentially his railroad was a long, narrow, litter box to that cat.

Correct Dave,

     The motion activated sprinklers worked wonders for them too !    Although there were a few time I forgot about it and got my own shower.  

John, I am trying to discourage the feral cat in my neighborhood, because I want to keep the fish that are in my pond.

Randy had an issue with a cat defecating in his ballast....essentially his railroad was a long, narrow, litter box to that cat.

With an outdoor layout, natures problems are part of the hobby.

The best deterrent I have found for my layout is a feral cat I adopted.

No squirrels, birds, and other varmints stick around long.

    Ron, I don't know if this helps, but I use rock...mulch drives me crazy.

    Oh, and an air rifle on the squirrels* (but never the birds; I like birds).

    *Don't tell anyone.

Joe Zullo said:

Maybe you could try rubber mulch?

I keep a flock of free range chickens.  They loved scratching the mulch in front of my house sending it all over the walkway and lawn.  I replaced it with the shredded rubber tire stuff and they rarely bother it now.  Added bonus - when heavy rain hits it doesn't splash "dirt" up on the house.

Well Ron, I have tried animal deterrent sprays, with limited success. I didn't run out right after each and every soaking rain, and the rain washed away the spray enough that the animals ran amuck.

The plastic owl didn't work long for my neighbor. They very soon figured out that the thing ain't real.

Another neighbor hung CDs from his tree, insisting that shiny things, twisting in the wind, scared animals away. Soon I was tempted to go explain his theory to the 3 deer standing in his yard eating his chrysanthemums.

So Ron, all I can do, is say what hasn't worked round these parts.

I have great sympathies for many railroaders in the United States.  Over time I have read about squirrels, deer, snakes, scorpions and all manner of unwanted visitors.  Luckily it is rare for railroaders in the UK to suffer from these varmints.

However, one problem I have had for around four years now, after getting another dog, is his desire to remove small figures and animals, plus the odd barrel or two and small lineside features from the ROW or station areas.  Consequently I had to remove all of these items which was a nuisance as they added to the ambience and interest.  I have had many dogs long before the railroad was built but knowing dogs propensity for chasing cats, birds or anything that they feel is an intruder, has meant no signals or other lineside features as they would not survive very long out there.

The occasional burying of small items of food, when an animal in not hungry, has been an inconvenience, but not on the scale of what Ron (the OP) has experienced.  One thing for sure is that outdoor railroads do require a fair amount of maintenance.

I've never tried it (I'm indoors) but looked at mulch lock spray as a possible product to use to hold down my ballast and scenery.  Might slow down your varmints and not make anything too permanent.

My problem was ground squirrels burying my track. Seems 'scale' dirt is easier to dig in .... I came home from a weekend away and found a drover's caboose and stock car nearly completely buried!

I'm now fully elevated and I use oversize ballast to keep birds from adding it to their gizzards .... 

Seems to be working.

Perhaps a motion activated sprinkler like this one may help?

https://www.amazon.com/Tangkula-Sprinkler-Outdoor-Activated-Repellent/dp/B07B9SZRS9/ref=mp_s_a_1_1_sspa?keywords=motion+activated+sprinkler&qid=1569951790&s=gateway&sprefix=motoon+ac&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUFRRkJBWVFGSzZXNEgmZW5jcnlwdGVkSWQ9QTA3Mjg4MjEyWTAxSkg2RzRMR0VXJmVuY3J5cHRlZEFkSWQ9QTA2NDUxOTAyR1RTRjJPOFpKWUM0JndpZGdldE5hbWU9c3BfcGhvbmVfc2VhcmNoX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

It solved a deer deer problem for me on my first layout.

Maybe you could try rubber mulch?

My wife and I will be going and may be bringing another couple with us. Already doing preliminary planning, and cost estimates to get the full experience. Not sure if I will be wearing club (ABTO, Arizona Big Train Operators) t-shirt or vest or just the name tag, but ya cant miss me!