Feeling unable to confront the duo, the teen instead kept an eye on them as they stood on the narrow walkway incidentally blocking his exit back to land.
Next thing Coleman had received a call from an unknown number.
"It was [her son] and he said to me, 'mum, some people just pushed me into the water. My phone's broken now."
Coleman dashed to Onerahi where she discovered her son soaking wet with goosebumps and missing his slip-on shoes that came off when he was underwater.
He told his mum how one of the men had approached him under the guise of wanting to learn how to cast a line.
"[Her son] stepped to the side to show him how to cast and that is when the guy pushed him in," Coleman said. "We're lucky because my son can swim but if they'd pushed off a person who was unable to things could've been a lot worse."
As the teen's head broke water the two men had already left with the puppy.
A fisherman nearby helped haul him out of the water, and he discovered the pair had taken the money from his wallet - $30 which is a lot of a teen not currently working, Coleman said.
Despite the incident, the teen has assured his mum that he won't be put off fishing – a hobby he's loved since he was 18 months old.
The Whangārei-based counsellor Coleman weighed her frustration that places where youngsters should be safe but weren't, against the idea the incident was a symptom of bigger problems.
"I'm upset that it happened but I understand that when you feel powerless in your life you do things like this ... it takes being shown empathy to be able to show it to others who are more helpless."
The family had not currently reported the incident to police or the SPCA because they felt they did not have enough information to identify the men.
People are encouraged to phone immediately 111 if they feel unsafe, or afterwards can phone 105 and visit their local police station.
