If you loved “Where’s Waldo?” books as a child, you might enjoy scouring photos for an adorable border collie named Momo.

Andrew Knapp began taking photos of his 4-year-old dog when he noticed how easily Momo seemed to disappear in his surroundings when they played fetch.

“When I'm about to throw a stick, Momo will run into the forest and become really still and wait for me to throw it. He's really good at sit-and-stay,” he said.

Knapp started taking photos of Momo’s disappearing trick and uploading them to the photo-sharing site Instagram with the hashtag #findmomo. But he never expected the photos to become so popular.

In addition to his popular hashtag — which has helped Knapp amass more than 35,000 Instagram followers — Momo also has a website where his photos can be viewed.

“Momo mostly started this project, I just happen to have the phone, Instagram and the cognitive abilities,” Knapp said.

How does Knapp find so many locations where Momo can just disappear?

“The key is not to look,” he says. “Mostly in nature, it's Momo — he runs and hides and I seek and snap. In the urban scenes, I usually have to make sure the location is nice to look at and safe.”

Knapp snaps a photo of Momo each day, and the popular black-and-white pup now has more than 150 pictures you can scour. Check out a few of them below. Can you find Momo?

Andrew Knapp

Andrew Knapp

Andrew Knapp

Andrew Knapp

Andrew Knapp

Andrew Knapp

Andrew Knapp

Andrew Knapp

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