Rescue dogs tend to be prone to seperation anxiety- especially when their new owners pay more attention to them than their previous owners. That can cause a huge emotional surge when you leave and come home. That surge makes them "loose their brain" a bit and things can happen.
My boy Taiko we got when he was just under 2 years old. He came from a great home, but he was a kennel dog so coming into a family of 3 with another dog was a big adjustment for him. From day 1 he showed signs of seperation anxiety. He missed his old regimented life and had to adjust to the odd routine we lived with. Today, I have to manage him carefully. When I leave, he is kenneled. My other dog is not because she doesn't destroy things when left out. Yet, Taiko has not earned that right yet. Minimally, your dog should be confined to only one room when you are gone. That makes the mess more bearable and actually makes the dog feel more secure.
Also, you need to provide a distraction while you are leaving and for up to at least 15 minutes from the time you leave. I use large "Greenies" and frozen Kong toys. I fill the kong toys with soup stock and kibble and freeze them overnight. I also have used peanut butter, but my dogs don't like the flavor as much so it doesn't work for the duration needed. Kongs work the brain and teeth. You don't want them fixating on your departure.
When I go, I just leave. No 'good bye pups" or anything. When I return, I let Taiko and Kita outside to do their business and check the mail, check email, do a load of dishes, I don't pay attention to them right away. No matter what they are doing to grab my attention. Both know it's not really worth their efforts to try for at least 15 minutes from my return.
Also, tired dogs are good dogs. My dogs get 30 to 40 minute walks almost every single day. I'm not sure how much staffies need, but I'm guessing they need some outlet for their energy. They are high drive dogs that want to use their brains and body. By the way, tiring out the brain by teaching tricks and such wears them out more than even physical excerscise. SO, my two go to weekly obedience classes as well. I figure it lets them use their brain for good and not evil.
THere's a book called "I'll be home soon" you can get from www.dogwise.com that should help a bit. Yet, just getting out and working the dog will help a lot as well. You might oddly enough consider getting a second dog to help you out with this one. It's not always the best fix. Yet, it can help. They both will still need attention, but they can entertain each other too. Instead of going ot the gym, is there a way you can go out jogging with this pup at least 2 nights a week? I think that would help a lot to relieve the excess energy he's got being penned up all day.
Hope that helps a bit. Keep writing if you have more questions.
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Chelle and the rest of the crew including, but not limited to Kita and Taiko (the shiba inu wrestle maniacs), Adi (reserved and dignified tabby cat), and all 28 reptiles
