"He was leashed in the back yard and somehow he just slipped off the leash," said Sheilah Graham, volunteer with

.

Bosco has been sighted on and off, so Missing Dogs of Massachusetts set a trap, with a camera monitoring it. Bosco re-appeared, walked up to it and went inside.

Graham called Bosco's owner minutes later.

"All I heard was him howling in the background and I knew instantly it was him...And I almost fainted because it's been two years," said Bill Ballato, Bosco's owner.

However, a face-to-face reunion between Ballato and Bosco is a bit complicated. Ballato has since moved to Colorado. They were able to see each other via FaceTime.

Ballato and Missing Dogs of Massachusetts are now working on a reunion plan.

"I have medical issues that prevents me from traveling," said Ballato.

While that plan comes together, the big question is what has Bosco been up to for two-plus years.

"They can survive any timeframe, they just revert back to their survival instinct," said Graham.

He was found near restaurants, and the trap was set by a nearby dumpster, so he was likely eating well.

"He's really a remarkable dog...Obviously," said Ballato.

Missing Dogs of Massachusetts has only been around for about a year. They've already helped more than 700 dog owners reunite with their lost pets.