A. 1. Learning to Work in the Presence of Another Animal
Start with single calm animal at a distance and behind a barrier. C/t for any looking or sniffing in that direction while staying calm.
Tip: If using the clicker or food excites your dog rather than calms him, try using a calm marker such as "Good" and a neck massage instead of food. You will need to make sure that your dog enjoys a massage at home first, to build value for it. Then practice the massage in a public context for just relaxing before using it in a training context.
Your dog will eventually start looking at the animal, then back at you in anticipation of getting the reward.
When she is doing that 5 or more times in a row, start clicking the looking back at you. When she is offering that consistently, you can also start naming the behavior “Look” so it comes under verbal cue control. (Tip: “Look” is usually used to get the dog to look at something whereas “Watch” is used to get your dog’s eye contact.)
At the beginning of later training sessions, cue the Look once, then cue simple or fun behaviors your dog knows in quick short bursts of 5 repetitions.
Give your dog a one minute break by moving further away, disengaging eye contact, then move back in and try cuing a few more quick behaviors.
When she is successful with several sessions of that, cue slightly more difficult behaviors.
Next, at that same distance, stop using the “Look” cue and just start cueing the simple behaviors. (Your dog shouldn’t need to look at the animal/person of interest before doing the cued behavior.)
Then try more difficult behaviors.
Next, decrease the distance a little.
Now start cueing simple or fun behaviors your dog knows in quick short bursts of 5 repetitions. Give your dog a one minute break, then try a few more.
When she is successful with several sessions of that, try slightly more difficult behaviors.
Decrease the distance again. Repeat as above.
Before you get too close to the animal, decide what is a safe distance and if or not you want your dog to actually interact.
If you choose to have her interact (generally not recommended until your dog is quick to focus on you voluntarily and able to perform more difficult behaviors in the presence of the distraction), make sure there are other knowledgable people handling the other animal(s), the other animals are still behind a barrier or restrained on a long line.
You must have a plan going into the situation! Watch both animals carefully for body language (to indicate stress levels) and move them apart quickly if they get stressed or things change for the worse.
Apply Premack's Principle to call your dog away from the distraction multiple times to strengthen the ability to ignore the distraction.
A. 2. One Animal-Sound of Animal
In many cases, it is wise to isolate the sound of the animal before the sight of the animal. For example, if barking dogs behind fences or the sound of the collar tags jingling triggers your dog, then start with just the sound. Here is are the sounds of 4 different dogs barking an intruder alert.
You can use audio clips such as this one, then progress to situations with live animals that you can control. For example a dog behind a window or in a car with closed or partially open windows. Ideally shaded so your dog can't see the barking dog as we want to isolate the sound from the motion. Then use a dog barking behind a solid wood fence far away, then closer.
A. 3. Staying Calm while in the Presence of the Other Animal.
Repeat as above but instead of cuing 5 simple behaviors, cue your dog settle at your feet or on a mat.
For this step, if you haven't already done it, switch to using a calm marker and massage as the reinforcer.
Start with short periods of time like 5 seconds. Then build up to 30 seconds and a minute. Cue your dog off the mat and pick it up and move further away for a break, then come back and try again. If your dog stay vigilant or gets excited at any point, increase the distance and/or shorten the duration.
Decrease the distance as your dog is able.
A. 4. Staying Calm while the Other Animal Moves Around You and Your Dog.
Repeat as above except this time you and your dog stay stationary and the other animal is moving on an arc or zig zag to approach you and your dog.
Having the other animal walk around you and your dog in a settle at the same distance changes things dramatically so have the other handler start even further away.
Only when your dog stays very calm with the other animal very close could they progress to decreasing the arc so they are gradually walking straight toward your and your dog on the mat.
B. Multiple Animals
When your dog is able to work with you fairly close to one animal, add a second and work your way from the beginning through the same process. Remember that adding a second animal may change the dynamics of the group so progress more slowly. Add a few more animals in the same way.
If you notice any predatory behavior on either your dog (intense staring that you cannot break, lowering of head, stalking especially silently, or the other animal toward your dog, stop the training and get professional help. Have your dog assessed for the degree of prey drive. A dog that have high prey drive towards other animals will not make a good service dog candidate for use in public places. This is a dog that will always have to be carefully managed in public and that defeats the purpose of your dog helping you. Instead, you would have to become more vigilant when you are out with him. Other animals can appear at any time in the most unexpected places.