Sudden On-Leash Reactivity

This is a place to gain some understanding of dog behavior and to assist people in training their dogs and dealing with common behavior problems, regardless of the method(s) used. This can cover the spectrum from non-aversive to traditional methods of dog training. There are many ways to train a dog. Please avoid aggressive responses, and counter ideas and opinions with which you don't agree with friendly and helpful advice. Please refrain from submitting posts that promote off-topic discussions. Keep in mind that you may be receiving advice from other dog owners and lovers... not professionals. If you have a major problem, always seek the advice of a trainer or behaviorist!


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Barked: Tue Jun 11, '13 6:56pm PST 
I adopted a one-year old border collie/retriever mix, Dexter, in December. He came with his fair share of quirks - barking at visitors, pulling on the leash, and shyness around strangers - but I was happy to discover he was excellent with other dogs both on and off leash.

Dexter showed some minor excitement when he spotted another dog during walks, but he never barked, even when the other dog did. He breezed through basic obedience classes over the winter, and was very polite with other dogs at PetSmart.

Recently, about 6 months after adopting him, he has developed sudden, unexpected and unexplainable on-leash reactivity. He is still very good with other dogs off leash, but while on leash, every time we pass another dog within a 20 ft range he lunges and barks and basically goes nuts. He is much more reactive to big dogs than small. I enrolled him in a loose-leash walking class recently and had to drop out because he spent half of the first class barking at a poodle across the room.

I also tried taking him to PetSmart this week and he exhibited the same behavior, barking and lunging at the dogs we saw when they were within 10 ft. I think that he is just frustrated that he can't get to the other dogs, but his bark is scary and I don't feel like I can take him out anymore.

I am so frustrated and confused as to why this has suddenly started! Dexter was such a great dog in social settings and I really want to be able to take him out in public again to places other than the dog park!

If anyone has any insight into sudden-onset reactivity, I would love to hear it!

OMG look Mom!- Another dog!
Barked: Thu Jun 13, '13 7:38am PST 
I am having the exact same problem with my dog right now and was going to post something similar today. Casey is one year old and we've had her a little over one month. One thing I found helpful was to take her to the dog park and meet other friend's dogs. Sounds like you're already doing that though. She had the same reaction at PetSmart last weekend when she saw two labs in the checkout next to us. She even almost came out of her collar trying to get to them. I can't tell you what's worked, but I can tell you what I plan to do. Keep going to dog parks and socializing off leash for sure. After spending some time inside the park I want to take her for a walk on leash outside the park and see if she reacts the same way even after spending time with a bunch of dogs. Another thing would be to take a step closer to the dog park when she is calm and turn back around any time she goes nuts. Give her a treat every time she is calm around another dog. I'm curious to see what others have to say though!