I have had limited success with "Boundary" animal repellent spray.

My previous neighbor was putting food out for the ferals, and we had 4 or 5 that liked my backyard (we didn't have dogs). I placed the repellent at the choke points where they entered and exited the yard. It worked for a couple of weeks, but I think they got used to it. The granules might have worked better.

I wanted to use Predator Pee mountain lion urine, but my wife was worried about attracting the real thing.

http://www.petco.com/product/4580/Lambert-Kay-Boundary-Indoor-Outdoor-Dog-and-Cat-Repellents.aspx

http://www.petco.com/product/6544/Repel-II-Dog-and-Cat-Repellent.aspx?CoreCat=certona-_-ProductList_Cat_1-_-Repel%20II%20Dog%20%26%20Cat%20Repellent-6544

http://www.predatorpee.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=LE&Category_Code=MLU

I started chasing them off, but they figured out real quick that when the door opens...run. Getting a clean shot is going to be difficult after a while. If you're really interested in harassing them, consider airsoft. My neighbor has been using them on noisy crows. Otherwise, contact the rescue operation and be prepared for a noisy night when pussy gets caught.
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