Michelle Chretien thought she would never see her dog again.

But, 10 days after her German shepherd rescue went missing in the Maple Ridge neighbourhood of Hammond, the Port Moody resident received a call from someone on a nearby island. They found her dog running along the beach.

Mercy, nine, managed to swim a kilometre across the Fraser River from about the Golden Ears bridge to the eastern tip of Barnston Island.

Chretien adopted Mercy from a rescue agency in Manitoba about two years ago. She had adopted dogs from the same agency before, and was confident in her abilities in dealing with dogs with behaviour issues.

However, with Mercy, nothing she did helped and she hired a dog behaviourist, who, after spending four months with the dog, diagnosed Mercy with post-traumatic stress disorder. That was a light bulb moment for the retired police dispatcher who has friends with PTSD and was familiar with many of the symptoms.

Mercy was put on several different medications but nothing really worked. She was, though, making a tiny bit of progress becoming slightly less skittish and less fearful.

“All I know about her past, obviously is that, whoever her first owner was, they badly abused her,” said Chretien.

Even going out for walks can trigger fear in Mercy who will simply shut right down, Chretien noted.

If there are too many people or too many dogs, Mercy will lie down on the road or the sidewalk and just stay there.

“I can’t move her. I can’t walk her,” Chretien said.

In order to help Mercy become more social, Chretien hired a dog walker to walk Mercy once or twice a week who has been doing that with success for the past two years.

So, when Chretien decided she wanted to take a couple of weeks vacation, she thought she would ask her dog walker to take care of Mercy while she was gone. But, just to be safe, she would see how Mercy did at her dog walker’s house for one day.

“I just thought, if she does OK for the day there, then I can go away for two weeks, she’ll be fine,” said Chretien.

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She dropped her off July 18.

However, the same day, Mercy broke right through one of the doors on the second floor and got out on the second floor balcony. She ran down the stairs and scaled the fence, almost two metres high.

Chretien put up a poster online on Missing Pets in BC that was shared widely and had search parties out every night – to no avail. Mercy would make an occasional appearance, noted Chretien, but nobody could get close enough to grab her.

Then all went quiet. All of a sudden, there were no new sightings of Mercy, which Chretien found odd.

Finally at 1 a.m. on July 28, Chretien received a call from a certified dog trainer with the BC SPCA, who lives on Barnston Island, that she first spotted Mercy running along the beach. She thought Mercy had either been dumped or that one of the island’s residents got a new dog.

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Then she saw Chretien’s poster. Chretien and Mercy were reunited at around 11:30 a.m. on July 28.

Chretien is amazed Mercy was able to swim that far. She would learn that a group of people were setting off fireworks at the Hammond Dog Park about three days prior to Mercy being discovered on Barnston Island. Chretien figures Mercy was spooked by the fireworks and took off running, right into the river.

“That’s one of her triggers – fireworks and fire crackers. She’ll just run. She’ll run into stuff to get away from them. Like she gets absolutely petrified,” said Chretien.

“So she probably just took off running and ran into the river and, I’m assuming, just kept going,” said Chretien.

When they were reunited Mercy whined a bit and her tail was wagging. That was good enough for Chretien since Mercy normally doesn’t show a lot of emotion since she mostly operates on fear.

Chretien said Mercy was exhausted by the time she arrived home.

But not tired enough to enjoy a chunk of feta cheese – one of her favourite treats.