Ok so people probably aren't going to agree with me and call me a bad pet owner and whatever, but this is my opinion:
As long as your raise your puppy right and only let it out with the birds under CLOSE supervision then you should be fine. When I got my dachshund puppy the vet said that she was going to eat my bird, because they have a SUPER strong prey drive. But guess what? she's afraid of my birds! I raised them right, and my bird bit the dog on her nose as a lil' pup so now Heidi (my dog) is scared. You can get a German Shepard, and you should be fine, depending on the training you give them. BUT, accidents do happen, and even a perfectly trained dog (or scared dog) can still change their attitude for just long enough to kill a bird. So I would say that you can get a dog, but train it well, supervise them if they are out together, and know that accidents can happen. Good luck!!
(also if you wanted a dog that sleeps under blankets all day long and is the laziest couch potato that you will ever meet, then I 100% suggest a mini-dachshund!!
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