Most foster homes already have one or more resident dogs. In fact, foster homes that don't have resident pets, and can therefore accommodate foster pups who aren't too friendly with other canines, are in short supply.
However, before adding a foster dog to your household for the first time, please take a moment to honestly consider whether this is everyone's best interests.
Some things you might ask:
- How does my dog get along with other dogs? If your dog is a dog park junkie, a regular doggie day care client, or otherwise heavily socialized with other members of her own species (including dogs of many different breeds, personality types, play styles, ages and genders), and does fine with all those other mutts, great! You're off to a strong start. However, if your dog has not been regularly socialized with other dogs (and this means unfamiliar other dogs, not just the same two best buds she's had since puppyhood), it's a good idea to spend some time letting her interact with other canines, and carefully observing those interactions, before bringing another dog into your household. Similarly, if your dog has any tendency to be a bully, plays too roughly for other dogs, gets over-excited when she sees other dogs, or otherwise displays questionable behavior, it is advisable to address that before trying to bring a new dog into the house. Don't rely on the foster dog to be the peacemaker. Make sure your own dog is rock steady, or as close to it as you can get, first.
- How does my dog tolerate other dogs in the house? A dog who likes the company of other canines outdoors may react differently when they intrude on his home turf. Invite a furry friend or two over for doggy play dates in your house, and observe them closely for any sign of problematic body language or conflict triggers (toys, chews, food bowls, doorways, favorite sleeping places, and proximity to the owner are common triggers). If your dog gets a little possessive about his food bowl, that's not necessarily a deal breaker, but it's something to be aware of and prepared to work around before the foster pup arrives.
- Can you devote individual attention to each dog? Not only will you have to train and work with each dog separately, but you will need to spend a little extra time cuddling and just enjoying each dog individually. They all need some of your undivided attention each day. Do you truly have the time and energy for each dog?
- Can you keep them separated if need be? There may be some conflict between the dogs, especially early on, that requires you to separate them for a while. Or they may need to be kept isolated for medical reasons. In the event that you need to keep them separated, can you do so?
If all indications point to "go," try to choose a foster pup who will be likely to get along with the resident dog. Generally your odds are best with a dog of the opposite gender who is slightly smaller and slightly younger than your own dog. If possible, look for a calm, tolerant, easygoing dog who is neither skittish nor overconfident.
The Big Meet
While most dogs do just fine with a furry temporary roommate, careful introductions can go a long way to defusing conflict and making the early days more enjoyable (or at least less frenetic) for all concerned.
It's best to do the initial introductions on neutral territory. If possible, choose a place where your dog is already used to meeting other dogs and has positive associations with such meetings. A dog park during off hours (very early morning or late at night, when no one else is there) can be a good choice. Tennis courts, small fenced-in parking lots, or a friend's fenced yard may be other possibilities. The area should be securely enclosed and small enough that you can catch the foster dog when you're ready to go or if the meeting starts to take a wrong turn. Leave the dogs on leash so you have something to grab if necessary. If initial indicators are good (polite sniffing, relaxed body language, big loose tail wags), drop the leashes and let them introduce themselves for a while.
If it's not a great idea to let the dogs meet off-leash (meaning, in this context, on dropped leashes) for some reason (maybe your dog can be a little pushy, or the foster pup seems extra shy, or you just don't have a safe secure location to let them roam), the initial introductions can be done on leash. Again, this should be done on neutral territory. You'll need two handlers, one for each dog. Walk the dogs parallel to one another at first, passing back and forth about 10' apart and observing how they respond to one another. Try to keep the leashes slack and free of tension. If the dogs react with curiosity and polite attempts to sniff, let them walk close enough to do so.
(In multiple-dog households, introduce each resident dog to the newcomer separately as described above. Start with the most easygoing dog and proceed from there, removing each resident dog before bringing in the next one. Dumping a new dog into the midst of a whole pack of strangers can be overwhelming; it's best to take things slowly.)
When it's time to go home, take the resident dog outside and bring the new dog inside first. Bringing a new, strange dog into a home already occupied by a resident dog can cause considerable tension; it's best to remove the resident dog from the household and let him come back inside to find the new dog already there. Supervise the initial meeting closely and keep it short: ten minutes is plenty of time. If there's any sign of serious tension (a little bit of posturing and an occasional snark is normal for most dogs), break the meeting up immediately and separate the dogs. If you have any doubt about your ability to introduce the dogs calmly and safely, ask for help. That first meeting sets the tone for the rest of their relationship. It's very important to get things off to a good start.
The next step is to encourage calmness and teach each mutt to associate good things with the other dog's presence. This may not necessarily be on Day One, especially if your foster pup is stressed and tired from transport; it's fine to do this a day or two later. One way of creating calmness is to put the new dog in her crate, and put your resident dog in a crate too if he has one. Try to arrange the crates close enough that the dogs can see each other without feeling threatened by closeness. Then hand out some long-lasting treats (stuffed Kongs, rawhides, bully sticks, or chew bones like Greenies, edible Nylabones, or Zuke's carrot bones) for each dog to gnaw on.
(Here is a quick video of my resident mutt Pongu and foster monster Crookytail gnawing on carrot bones together a few hours after Crookytail's arrival. Neither one is a resource guarder, and I was completely comfortable with both dogs' body language, so they're not separated by crates and they are in very close proximity for a first-day exercise. By Day Two, they were even closer. Note that in the second video they're chewing on plastic bones, not edible treats -- a lower-value chew that is less likely to provoke jealousy. Work slowly, keeping a careful eye on the dogs' comfort level, but do encourage them to get more comfortable with one another over time.)
Train the dogs individually, keeping one dog crated while you work with the other. Later you may be able to put one dog on a Sit/Stay while working with the other (don't forget to reward that Stay, too!) but that is fairly advanced -- not just for the dog maintaining the Sit/Stay, but for the other dog, who is being expected to work past the distraction of a fellow mutt in close proximity -- and I don't often have a foster dog long enough to reach that level. Early on, it's best to work separately and rely on the crate to maintain distance.
However, whenever you catch the dogs relaxing next to each other, it's a good idea to reward them for that calmness with a word of praise, a little petting, or a small medium- to low-value treat for each one. (For this specific purpose, don't reward with games or toys; that gets them excited again, which is the opposite of what you want!) Rewards should be small and low intensity, but frequent. The more you reward your dogs for calmness in this manner, the more relaxed they'll be.
Long-term management of a multi-dog household is beyond the scope of this post. However, Patricia McConnell's booklet "Feeling Outnumbered? How to Manage and Enjoy Your Multi-Dog Household" and Debby McMullen's book "How Many Dogs?!" are excellent resources for practical tips on how to live semi-sanely with more than one mutt.