Management is always first:

• For now, your dog must always on-leash where these TDAs are likely to be. Why? Because every time your dog practices chasing them, they get better at it and it becomes more and more reinforcing. 
• When YOU notice the TDA, do a food scatter. Say "scatter!" or "find it!" and scatter a few snacks. Keep scattering a few snacks at a time so they keep eating and eating and eating. Sometimes this prevents the chaos when they do notice. 
• When THEY notice the TDA, do a food scatter. Same as above. It can help them recover and prevent them from going ballistic. 
• When you think you have access to their brain, happy-talk them in a different direction and reinforce them well for coming along with you. Remember that you have to be exciting - boring will not compete well with a TDA. 

Training when you're not managing (above)

List of supplies:

• leash & harness (avoid using a collar if the dog is lunging/pulling)
• clicker (optional but highly recommended if your dog has been conditioned to one already. This speeds up the process MUCH faster than using a verbal marker, like "yes". 
• very high-value food rewards (must be real food - chicken, meatball, cheese, etc... vs hard, crunchy treats, or kibbles)
• Treat pouch or bait bag to store said food rewards
• novel tug-toy with or without a squeaker (this is my personal favourite)

STAGE ONE:

• Find a spot where you can watch TDAs from a safe distance (this might be in your front window, back door, or your car in a park parking lot, or on a park bench) and be armed with some AMAZING tiny snacks . Your dog must be on-leash or otherwise unable to get to these TDAs. 
• Be ready. Have your pouch FULL and your hand full, too (behind your back). When your dog notices the TDA, immediately, say your cue ("find it" or "scatter") and scatter a few snacks. Keep scattering a few snacks at a time so they keep their head down, eating. Do this until you've doled out 10 small treats (approximately).
• If your dog pulls back towards the TDA, repeat your food scatter until the TDA is gone, OR you have maxed out at 5 food scatters and can move away yourself for a break. 

STAGE TWO:

• Find a spot where you can watch TDAs from a safe distance and be armed with some AMAZING tiny snacks . Your dog must be on-leash or otherwise unable to get to these TDAs. 
• Be ready. Have your pouch FULL and your novel tug toy ready (behind your back). When your dog notices the TDA, immediately, say your cue ("find it" or "scatter") and scatter a few snacks. Keep scattering a few snacks at a time so they keep their head down, eating. Do this until you've doled out 10 small treats (approximately).
• Then, immediately make a crazy exciting sound (I like using a crazy alien noise, kissy noises, brrrrreeeeee!!!! etc) and grab that tug toy! Wiggling the tug toy along the ground (must be horizontal unless you want to lose a couple fingers here...), entice your dog with it and let them get it! Hold onto the handle and provide little movement while they tug on it and you move away from the TDA. 
• With your other hand, grab a few pieces of food and do a food scatter to help them release the tug, and calm down a little. Tuck the tug toy away for the next rep. 

STAGE THREE:

• Find a spot where you can watch TDAs from a safe distance  and be armed with some AMAZING tiny snacks . Your dog must be on-leash or otherwise unable to get to these TDAs. 
• Be ready. Have your pouch FULL and your clicker in your leash-hand. When your dog notices the TDA, immediately click and then grab a few pieces of food and scatter them on the ground away from the TDA. Be ready to do it again, since your dog will eat and look back at the TDA. You'll click/feed every time they look at it. 
• If your dog doesn't reorient to you instantly after the click, put the food in front of their face and lure their face away and scatter the food. This helps them disengage faster the next time. Repeat this way as needed until they do instantly reorient to you after the click. When that starts happening more reliably, you can move onto Stage Four! 

STAGE FOUR:

• Find a spot where you can watch TDAs from a safe distance  and be armed with some AMAZING tiny snacks . Your dog must be on-leash or otherwise unable to get to these TDAs. 
• Be ready. Have your pouch FULL and your clicker in your leash-hand. When your dog notices the TDA, wait for 1-2-3- and see if your dog reorients to you automatically. If they do, immediately click and then grab a few pieces of food and scatter them on the ground away from the TDA. Be ready to do it again, since your dog will eat and look back at the TDA. You'll click/feed every time they look at it and then look back at you!
• As you both get better at this game, you can put the clicker away, use a verbal marker, and alternate the use of (less) food and the tug toy!