How does a seeing eye dog let its owner know when to scoop its poop?

The dog adds a scent to his feces.

No. No blind person is expected to fumble around on the ground to find a pile of shit. And some dogs make a trail of shit. Do you know how many turds your dog drops when he/she unleashes a load??? Or which direction they took when they did it?

@kritiper Your dog is always supposed to be on a leash; especially if it is a seeing eye dog. If you are roaming in the woods, that is a different story.

I would go with @rebbel‘s answer and also note, that the owner could sense when the dog is pausing for relief. I suspect this issue since it would be fairly common is part of the training.

I googled and found this:

https://blindlowvision.org.nz/guide-dogs/our-puppies/who-picks-up-guide-dog-poop/

@janbb Leash or no leash, no blind person is going to be expected to fumble around on the ground for dog shit. And who is to say what the dog might be doing (or shitting) while this blind person is fumbling around?? Like I said before, not all dogs shit in one spot.
Face it. You can clean up some of the dog’s shit all of the time, and you can clean up all of the dog’s shit some of the time, but you can’t clean up all of the dog’s shit all of the time.

@kritiper Did you see @jca2‘s link? It makes it quite clear and verifies what I wrote. Anyway, not worth arguing about for sure.

I don’t do links. It takes too long to download.

@kritiper Well, in this case, it was the answer. Too long, didn’t download, they train the dog to poop or pee on command and when appropriate.

@kritiper Are you on a 56k dial-up modem?

@kritiper: Click on it and it opens in two seconds.

Our Dakota used to poop and pee while walking. I always wondered if she was trying to convince other dogs that there was more than one of her.