Deacons, sorry to not answer earlier, but I’ve had computer problems compounded by the previous slowness of the boards.
It certainly sounds like your cat is responding to the stray cats she can see outside. Some cats are more just more territorial than others. I’m not sure that there is a lot you can do with YOUR cat in this situation, as she is responding to instinct and doesn’t have much (if any) conscious control over that she is doing.
The best solution is to prevent the stray cats from wandering around on your property. I don’t know how practical that would be for you as I don’t know anything about your housing situation. Other possibilities include blocking her access to the windows, covering the windows so that she can’t see out, etc., but those are also hard to manage, plus deprive your cat of her pleasure in viewing the outside world.
However, since you now have a pretty good idea why and where she is doing this, you might consider trying a product called Feliway. Feliway comes in a small spray bottle and contains feline facial pheromones, which are another marker used by cats - they deposit these pheromones whenever they rub their cheeks against objects. Research indicates that cats will not urinate wherever they have placed facial pheromone markers. For some reason these pheromones also seem to reduce anxiety - since facial marking seems to be a ‘friendly’ gesture among cats, I suppose the pheromones trigger warm, fuzzy feelings rather than aggressive ones.
Feliway is, in my experience, at least somewhat effective in preventing urinary marking. It is just not practical in many cases, as it needs to be re-applied daily (not something you want to do to an entire room or house!); however, in your situation applying it in the areas she is targeting may solve the problem. I don’t know if continuous use will eventually ‘re-train’ her instinctive response, but its possible that the artificial ‘friendly pheromone’ stimulation she receives at these locations will permanently modify her attitude towards seeing strange cats in her territory. I would love to know if this does happen, as it would be nice to know if instinctive behavior can be permanently (or even semi-permanently) modified in this manner.
You might also try the Feliway at your basement door - the pheromones may confuse her enough that she will quit trying to tear up your carpet. The vinegar might also work if she is reacting to the smell of mice or something - I don’t know if it will help if she is reacting to the sound of something small skittering around. It’s worth a try!
Feliway can probably be found at most of the large pet-supply sites and/or stores. Revival Animal Health has it in their catalog, so I assume you can order it from their website at http://www.revivalanimal.com . The price has certainly come down from when I tried it! I paid $40.00 for a bottle several years ago, and the price was one reason I didn’t continue using it. Revival has it for $19.95, and the price should be similar elsewhere.
Anyway, this is what Revival says about Feliway:
“Feliway has some of the properties of feline facial pheromones. Pheromones are chemical substances secreted by animals to confirm their territory, to communicate with others & familiarize themselves with their environment. Facial pheromones will inhibit urinary markings when applied to an area. Feliway may be used to stop or prevent urinary marking by cats. Also useful in comforting a cat in an unknown or stressful environment (cage, car, boarding, new house). Will not stain or mark.”
FWIW, Feliway did stop one of my stud cats from spraying his inside enclosure, but I had to apply it to the lower 2 feet of all of the walls (of a 10’x12’ room), his door, the walls near his shelf perches, his climbing post . . . at $40 a bottle, it just wasn’t worth it. I decided it was easier and cheaper to build outside habitats where the boys can spray to their hearts’ content. It DID seem to work for the short time I used it.
Hope this helps!