They’d seen each other a few times before, a pair of dog lovers walking the trails under the Sewalls Falls Bridge in Concord.

They’d smile, nod, say hi – common behavior among dog lovers, who often know a dog’s name before they know the owner’s name. That was the case Wednesday, under the bridge, on a trail near the Merrimack River.

But by time Taury Anderson and Rob Cary, both of Concord, moved into view in the boat launch parking lot shortly before 1 p.m., trailed by three emergency responders, their leashed dogs leading the way in front of the pack, they knew the other’s name and had built a bond with iron-like strength.

“We know our names now,” Anderson said.

That’s what happens when you save the life of a dog that does not belong to you. Cary’s dog, Zoe, a blue tip coon hound and rescue from Mississippi, had fallen through ice on the Merrimack and struggled to lift herself up, using her front paws only. Exhausted and shivering, she simply wasn’t able to do it.

That’s when Cary called 911. He was told firefighters would be there soon. Meanwhile, Anderson, who was walking her dog, Puzzle, and a friend’s dog, Rondo, spotted Zoe struggling and Cary chopping through ice in an attempt to build a path with shallower water to increase the chance that Zoe could swim or walk back to shore.

Anderson busted through the soft ice with her fists, jumped into the waist-high water and moved toward Zoe. She cleared some ice chunks, giving Zoe room to move from her prison and swim to shore, where Cary pulled her in, onto land.

“The ice was not strong enough to get onto it so there was no way you could walk on it,” said Anderson, a software engineer. “It was just best to move through it.”

Once she reached Zoe, 30 feet from shore, Anderson said the dog was “pretty scared, growling, like she was saying, ‘Don’t get near me.’  I moved the ice out of the way so she could swim back and move through that trail.”

Five emergency vehicles, including a trailer carrying three rescue boats, one of which had a motor, arrived before firefighters climbed down an embankment, rushing to the scene of what could have been a tragic outcome.

By then, though, the rescue had been completed. Cary, Anderson and Zoe were wet and cold, on a day with unseasonably high temperatures, reaching the high 50s.

That begged the question: How did Zoe end up on the ice?

“I can let her off her leash and let her run,” Cary said. “We have our routine and I will blow a whistle and she will come back and I will give her a treat and then she goes out again. She’s never gone out on the ice before, then four seconds later, she is right over there, and, boom, she falls right through.”

He called the fire department, moved back near Zoe and began to build his icy, makeshift gully.

“I was going to get them (firefighters) coming in and then get back (to Zoe) when Taury came along,” Cary said.

“I’ll go get her,” Anderson said she told Cary.

“That’s when I heard the angels,” Cary said.

Anderson is tough. She’s competed a few years with the Granite State Roller Derby team. Her derby name, Russian Roulette, was shown below the left shoulder on her jacket.

“I ended up breaking the ice with my roller derby fists,” Anderson said.

Cary also caught another break: Anderson once lived in a home with no running water. She’d clean herself in Pleasant Lake, and that included in the winter. “Very cold,” she said.

The nature of their relationship has changed, probably forever. Anderson and Cary will continue to see each other while walking their dogs. They may have more to say to each other than before.

“We only knew our dogs’ names,” Anderson said. “Now, we’re all best friends.”