Adopted Jack Russell - Very Aggressive Towards Men and Sudden Movements
About a month ago, I adopted a 5 year old Jack Russell Terrier. She was found as a stray last December and had been in the adoption center since. During this time, she stayed with two foster families and one of the families had a incident where the dog bit someone. I was told all of this before the adoption but according to the foster family, they believed it was the dog reacting to the person aggressively playing with her. Since I've brought her home, she has almost been a perfect dog. She's had no accidents. Hasn't destroyed anything and overall been such a pleasure to have. The only problem there was, was walking. She doesn't like when she doesn't see something coming and she's barks when a bike comes by suddenly or we turn a corner and there is someone there, just as examples. But lately, the problems have escalated. I don't have that many visitors but in the last month I have had friends over and she absolutely reacts aggressively when I have men in my apartment. Two days ago, I had a date come back to my apartment to use the bathroom. I told him before hand that she doesn't like new people and she was going to bark so just be ready. I entered the apartment with him, Robin (my dog) did bark but I picked her up and went into the other room while he used the bathroom. I then put her on a lease and we walk downstairs to take her out. We were outside and he bent down to pet her and she freaked out and bit his nose. I didn't
know what to do. We went back up to my apartment. I put her in my room and helped him because he was bleeding quite a bit. She has all her shots and I apologized over and over but what do I do with the dog? This was an extreme situation which I could have put behind me until yesterday. When I had another friend come to the apartment. Even before the bite incident, I try to introduce any person to Robin in a controlled situation when I am home and I'm letting someone in. I put Robin on her lease and then go down stairs with her to let the person in. After the biting incident on Friday, I was really cautious yesterday. My friend simply held his hand out for Robin to sniff, she did bark when he came in the door but calmed down and my friend again let her sniff him before moving into my apartment. He put his stuff down and moved further into my kitchen and Robin snapped at him. I still had her on her leash so she missed him but what do I do? I can't have a dog that bites people. I don't understand because she's never been aggressive towards me and I've had her in other situations with other people and she has barked but hasn't snapped or actually bit someone. Any advise someone can give me, I'd really appreciate it. Is this a Jack Russell trait? Is it more likely she was abused? What can I do help this problem? I love my dog and she is so sweet usually but this has become a serious problem?