Dogs have strong territorial instincts. This makes it somewhat complicated when you marry or move in with someone who also has a dog and you have to merge multiple pets into one household. Simply bringing unacquainted dogs together under one roof without a plan is likely to trigger major fights, especially with animals of the same sex or if one dog is moving into another dog's territory. With some patience and proper procedure, though, you can introduce the dogs in a way that minimizes how threatened they feel and allows them to sort out their natural hierarchy peacefully. An appropriate introduction is key to happy coexistence.
If You're All Moving into a New Home
1 - Bring the dogs together in a neutral place they're all unfamiliar with to prevent strong feelings of territoriality. Keep them on leashes, with you and your spouse each handling your own dogs.
2 - Allow the dogs to sniff each other. This is how they meet and greet. Talk positively to encourage the dogs.
3 - Rein the dogs in after an initial meeting of a minute or so and offer treats and praise. Allowing the dogs to investigate each other for too long can lead to escalation of aggression.
4 - Encourage the dogs to interact again after a few minutes apart. Watch their body language closely. If one dog lowers her front half and raises her rear, it's a playful sign that the meeting has gone well. If either dog shows signs of fear or aggression -- such as growling, baring teeth, prolonged staring or raised hairs on the back -- proceed with caution. Talk in upbeat tones, offer plenty of treats and continue to break up and briefly reintroduce the dogs until they calm down. Wait until they're getting along well before bringing them home.
5 - Take the dogs to your new home in the same car if the meeting went well, you have enough space in your vehicle and the dogs don't get stressed during travel. Otherwise, take them separately. Let them inside together.
If One Person Moves into the Other's Home
1 - Confine the resident dog in her crate or a small room where you often confine her. Bring the new dog into the house without allowing the resident dog to see her. Confine the new dog in her crate or another small room. The dogs will smell each other and be aware of each other's presence, but do not allow any visual contact at this point in the introduction process.
2 - Keep the dogs apart and prevent visual contact for a few days. Let the dogs out one at a time. Allow the new dog to roam the house, sniff the other dog's scent and leave her own scent markings. Allow the resident dog to smell the new dog's markings as she makes her way around the house. Comfort her with love, positive tones and treats if she becomes stressed.
3 - Give each dog a favorite toy or blanket from the other dog while they're confined. Leave the item with the other dog for an hour or so a few times per day during the few days when there is no visual contact. This allows each dog to get intimately acquainted with the other's scent and become comfortable with it.
4 - Wait until the resident dog stops getting upset by the new dog's scent when she roams the house to introduce the animals face to face.
5 - Bring the dogs separately to a neutral location for the first visual meeting. Still prevent them from seeing each other. Don't do it in the home, your yard or a familiar park, or territorial instincts may kick in. Have the first meeting at someone else's house.
6 - Let one dog play alone in the chosen location for a little while. Then, return her to her crate out of sight. Let the second dog play alone in the area and identify the other dog's familiar scent.
7 - Release the confined dog and allow her to join the other in the neutral space. This should be the first time they see each other. Allow them to approach and sniff each other at will. It should go smoothly.
8 - Take the dogs home after they've stopped sniffing each other and showing any hesitancy. If you have enough room and if traveling isn't stressful for either dog, you can take them in the same vehicle. Release them at home at the same time.
Warning - Dogs can be seriously injured or even killed when they have territorial fights. If you and your spouse's dogs don't get along, a professional animal behavioral therapist should handle bringing them together.
By Jon Mohrman
About the Author
Jon Mohrman has been a writer and editor for more than seven years. He specializes in food, travel and health topics. He attended the University of Pittsburgh for English literature and San Francisco State University for creative writing.